:root {
  --bg: #f6f6f6;
  --surface: #ffffff;
  --surface-soft: #f1f1f1;
  --text: #17191c;
  --muted: #68727a;
  --line: #dedede;
  --accent: #2563eb;
  --accent-strong: #111827;
  --blue: #2563eb;
  --warm: #d7a84f;
  --sand: #d8d8d8;
  --radius: 8px;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.6;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(246, 246, 246, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(18px);
}

.section-shell {
  width: min(1160px, calc(100% - 40px));
  margin: 0 auto;
}

.nav-shell,
.footer-shell {
  width: min(1500px, calc(100% - 64px));
  margin: 0 auto;
}

.nav-shell {
  height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: 0;
}

.brand-mark {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: url("/assets/images/brand/aistudy-logo-96.png") center / 78% no-repeat, #fff;
  border: 1px solid #e4e4e4;
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.08);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  color: #444;
  font-size: 14px;
}

.site-header .nav-links a,
.site-header .nav-links button {
  min-height: 38px;
  padding: 8px 12px;
  border-color: transparent;
  background: transparent;
  color: #333;
}

.site-header .nav-links a:hover,
.site-header .nav-links button:hover {
  border-color: #d8d8d8;
  background: #fff;
}

.site-header .nav-links .button.primary {
  background: #111827;
  border-color: #111827;
  color: #fff;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.12);
}

.site-header .nav-links span {
  color: #333;
  font-size: 14px;
}

.nav-links a,
.button,
button {
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  min-height: 42px;
  padding: 10px 16px;
  border-radius: var(--radius);
  font: inherit;
  cursor: pointer;
}

.button.primary,
button.primary {
  background: var(--accent-strong);
  color: #fff;
  border-color: var(--accent-strong);
}

.button.ghost {
  background: transparent;
}

.button.disabled {
  pointer-events: none;
  opacity: 0.35;
}

.hero {
  padding: 52px 0 18px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(360px, 0.9fr);
  gap: 48px;
  align-items: center;
}

.eyebrow {
  color: var(--accent-strong);
  font-size: 14px;
  font-weight: 700;
  margin: 0 0 16px;
}

h1,
h2,
h3 {
  letter-spacing: 0;
  line-height: 1.18;
}

h1 {
  font-size: clamp(40px, 5.2vw, 66px);
  margin: 0 0 22px;
  text-wrap: balance;
}

.nowrap {
  white-space: nowrap;
}

h2 {
  font-size: clamp(26px, 2.15vw, 34px);
  margin: 0 0 16px;
}

h3 {
  font-size: 20px;
}

.lead {
  max-width: 680px;
  color: var(--muted);
  font-size: 19px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  margin-top: 32px;
  flex-wrap: wrap;
}

.hero-proof {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 30px;
  max-width: 640px;
}

.hero-proof div {
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.hero-proof strong {
  display: block;
  font-size: 28px;
  line-height: 1;
}

.hero-proof span {
  display: block;
  color: var(--muted);
  font-size: 13px;
  margin-top: 8px;
}

.hero-visual {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px;
  box-shadow: var(--shadow);
}

.h5-showcase {
  padding: 14px;
  display: grid;
  gap: 12px;
  justify-items: center;
  background: #fbfbf8;
}

.h5-phone-frame {
  width: min(300px, 100%);
  margin: 0;
  padding: 8px;
  border: 1px solid var(--line);
  border-radius: 26px;
  background: #111;
  box-shadow: 0 24px 70px rgba(23, 25, 23, 0.16);
}

.h5-phone-frame img {
  display: block;
  width: 100%;
  border-radius: 18px;
}

.shot-caption {
  width: 100%;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  padding: 2px 4px;
}

.shot-caption span {
  color: var(--muted);
  font-size: 13px;
}

.shot-caption strong {
  font-size: 14px;
  text-align: right;
}

.product-board {
  padding: 18px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(248, 248, 248, 0.96)),
    repeating-linear-gradient(90deg, transparent 0, transparent 38px, rgba(0, 0, 0, 0.035) 39px);
}

.board-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 18px;
  padding: 6px 4px 18px;
  border-bottom: 1px solid var(--line);
}

.board-head span,
.panel-label {
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.product-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  padding: 16px 0;
}

.product-panel {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.86);
  border-radius: 12px;
  padding: 18px;
}

.product-panel h3 {
  margin: 6px 0 14px;
}

.mini-route,
.schema-row,
.metric-line {
  border: 1px solid #e4e4e4;
  background: #fafafa;
  border-radius: 8px;
  padding: 10px 12px;
  margin-top: 8px;
}

.mini-route.active {
  background: #f1f1f1;
  border-color: #d2d2d2;
  color: var(--accent-strong);
  font-weight: 700;
}

.schema-row {
  display: grid;
  grid-template-columns: 118px 1fr;
  gap: 10px;
}

.schema-row span {
  font-weight: 700;
}

.schema-row em {
  color: var(--muted);
  font-style: normal;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.admin-panel {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
}

.admin-panel .panel-label,
.admin-panel h3 {
  grid-column: 1 / -1;
}

.metric-line {
  margin-top: 0;
}

.metric-line strong {
  display: block;
  font-size: 24px;
}

.metric-line span {
  color: var(--muted);
  font-size: 13px;
}

.board-flow {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
  color: var(--muted);
  font-size: 13px;
}

.board-flow span {
  padding: 7px 10px;
  background: var(--surface-soft);
  border-radius: 999px;
  white-space: nowrap;
}

.board-flow i {
  flex: 1;
  height: 1px;
  background: var(--line);
}

.section,
.problem-section,
.promise-section,
.method-section,
.compare-section,
.value-section,
.outcome-section,
.final-cta {
  padding: 56px 0;
}

.problem-section {
  padding-top: 34px;
}

.split-list {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(420px, 1fr);
  gap: 58px;
  align-items: start;
}

.problem-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.problem-list div {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 18px;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.problem-list span {
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.problem-list strong {
  font-size: 20px;
  line-height: 1.45;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 30px;
}

.section-heading.narrow {
  max-width: 700px;
}

.section-heading h2 {
  margin-bottom: 0;
}

.promise-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.promise-grid article {
  min-height: 190px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 26px;
  box-shadow: 0 12px 40px rgba(25, 47, 64, 0.04);
}

.promise-grid h3 {
  margin: 0 0 14px;
  font-size: 26px;
}

.promise-grid p {
  color: var(--muted);
  margin: 0;
}

.method-section {
  background: #fff;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.process-line {
  display: grid;
  grid-template-columns: repeat(9, minmax(0, 1fr));
  gap: 8px;
  margin-top: 34px;
}

.process-line span {
  min-height: 84px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
  border: 1px solid var(--line);
  background: #fafafa;
  border-radius: 8px;
  color: var(--muted);
  font-weight: 700;
  text-align: center;
}

.process-line span.strong {
  background: var(--accent-strong);
  border-color: var(--accent-strong);
  color: #fff;
}

.method-note {
  margin: 18px 0 0;
  color: var(--muted);
  text-align: right;
}

.compare-table {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  align-items: stretch;
  gap: 12px;
}

.compare-col {
  display: grid;
  grid-template-rows: auto repeat(4, minmax(56px, auto));
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  overflow: hidden;
}

.compare-col h3,
.compare-col p {
  margin: 0;
  padding: 18px 20px;
  border-bottom: 1px solid var(--line);
}

.compare-col h3 {
  background: #fafafa;
}

.compare-col p {
  color: var(--muted);
}

.compare-col p:last-child {
  border-bottom: 0;
}

.compare-col.featured {
  border-color: #d4d4d4;
  box-shadow: var(--shadow);
}

.compare-col.featured h3 {
  background: var(--accent-strong);
  color: #fff;
}

.compare-col.featured p {
  color: var(--text);
}

.section-intro {
  display: flex;
  justify-content: space-between;
  gap: 28px;
  align-items: end;
  margin-bottom: 30px;
}

.section-intro p {
  max-width: 560px;
  color: var(--muted);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.value-section {
  background: #fff;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.value-grid {
  display: grid;
  grid-template-columns: minmax(260px, 0.8fr) minmax(0, 1.2fr);
  gap: 44px;
}

.value-intro h2 {
  margin-bottom: 0;
}

.value-list {
  display: grid;
  gap: 14px;
}

.value-list article {
  display: grid;
  grid-template-columns: 52px 1fr;
  gap: 8px 18px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 18px;
}

.value-list article:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.value-list span {
  grid-row: span 2;
  color: var(--accent-strong);
  font-weight: 800;
}

.value-list h3 {
  margin: 0;
}

.value-list p {
  margin: 0;
  color: var(--muted);
}

.outcome-section {
  padding-top: 58px;
}

.outcome-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.outcome-grid div {
  min-height: 126px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: 10px;
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 12px;
  padding: 18px;
}

.outcome-grid strong {
  font-weight: 700;
}

.outcome-grid span {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}

.audience-section {
  background: #fafafa;
}

.final-cta {
  text-align: center;
  background: var(--text);
  color: #fff;
}

.final-cta h2 {
  max-width: 760px;
  margin: 0 auto 14px;
}

.final-cta p {
  margin: 0 auto;
  max-width: 560px;
  color: rgba(255, 255, 255, 0.72);
}

.final-cta .button.primary {
  background: #fff;
  color: var(--text);
  border-color: #fff;
}

.final-cta .button.ghost {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.24);
}

.hero-actions.centered {
  justify-content: center;
}

.faq-section {
  background: #fff;
}

.topic-section {
  background: #fafafa;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.topic-grid a {
  min-height: 260px;
  display: grid;
  align-content: start;
  gap: 14px;
  padding: 26px;
  border: 1px solid var(--line);
  background: #fff;
  transition: transform 160ms ease, border-color 160ms ease, box-shadow 160ms ease;
}

.topic-grid a:hover {
  transform: translateY(-2px);
  border-color: rgba(37, 99, 235, 0.45);
  box-shadow: 0 18px 52px rgba(0, 0, 0, 0.08);
}

.topic-grid span {
  color: var(--accent);
  font-size: 13px;
  font-weight: 800;
}

.topic-grid strong {
  color: var(--text);
  font-size: 26px;
  line-height: 1.16;
}

.topic-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.8;
}

.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.faq-grid article {
  min-height: 180px;
  display: grid;
  align-content: start;
  gap: 12px;
  padding: 24px;
  border: 1px solid var(--line);
  background: #fafafa;
}

.faq-grid h3 {
  margin: 0;
  color: var(--text);
  font-size: 22px;
  line-height: 1.25;
}

.faq-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.8;
}

.seo-page-main {
  background: #fff;
}

.seo-hero {
  padding: 86px 0 56px;
  border-bottom: 1px solid var(--line);
  background: #f6f6f6;
}

.seo-hero h1 {
  max-width: 980px;
  margin: 0;
  font-size: clamp(42px, 6vw, 82px);
  line-height: 1.02;
}

.seo-hero .lead {
  max-width: 920px;
}

.seo-section {
  padding: 64px 0;
  border-bottom: 1px solid var(--line);
}

.seo-section h2 {
  max-width: 900px;
  margin: 0 0 22px;
  font-size: clamp(32px, 4vw, 54px);
  line-height: 1.08;
}

.seo-section > .section-shell > p,
.seo-section .seo-lead {
  max-width: 940px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.9;
}

.seo-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 26px;
}

.seo-grid article,
.seo-list article {
  padding: 24px;
  border: 1px solid var(--line);
  background: #fafafa;
}

.seo-grid h3,
.seo-list h3 {
  margin: 0 0 10px;
  font-size: 22px;
  line-height: 1.25;
}

.seo-grid p,
.seo-list p {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.8;
}

.seo-list {
  display: grid;
  gap: 12px;
  margin-top: 26px;
}

.article-card-grid article {
  display: grid;
  align-content: start;
  gap: 10px;
}

.article-label {
  width: fit-content;
  padding: 6px 10px;
  border: 1px solid #e1e1e1;
  background: #fff;
  color: #555;
  font-size: 13px;
  font-weight: 800;
}

.seo-grid h3 a {
  color: inherit;
  text-decoration: none;
}

.seo-grid h3 a:hover {
  color: var(--accent);
}

.article-topic-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 26px;
}

.article-topic-list div,
.article-topic-list a {
  min-height: 126px;
  padding: 22px;
  border: 1px solid var(--line);
  background: #fafafa;
  color: inherit;
  text-decoration: none;
  transition: transform 160ms ease, border-color 160ms ease, box-shadow 160ms ease;
}

.article-topic-list a:hover {
  transform: translateY(-2px);
  border-color: rgba(37, 99, 235, 0.45);
  box-shadow: 0 16px 44px rgba(0, 0, 0, 0.08);
}

.article-topic-list strong,
.article-topic-list span {
  display: block;
}

.article-topic-list strong {
  margin-bottom: 10px;
  color: var(--text);
  font-size: 20px;
}

.article-topic-list span {
  color: var(--muted);
  font-size: 15px;
  line-height: 1.75;
}

.article-body {
  max-width: 980px;
  margin: 0 auto;
}

.article-body .seo-section {
  padding: 56px 0;
}

.article-body h2 {
  max-width: 860px;
}

.article-body p {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.9;
}

.article-flow {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 10px;
  margin: 28px 0;
}

.article-flow div {
  min-height: 116px;
  padding: 18px;
  border: 1px solid var(--line);
  background: #fafafa;
}

.article-flow span {
  display: block;
  margin-bottom: 18px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 900;
}

.article-flow strong {
  display: block;
  color: var(--text);
  font-size: 18px;
  line-height: 1.35;
}

.knowledge-table {
  width: 100%;
  margin: 28px 0;
  border-collapse: collapse;
  background: #fff;
}

.knowledge-table th,
.knowledge-table td {
  padding: 18px;
  border: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.knowledge-table th {
  background: #f6f6f6;
  color: var(--text);
  font-size: 15px;
}

.knowledge-table td {
  color: var(--muted);
  font-size: 16px;
  line-height: 1.75;
}

.article-note {
  margin: 28px 0;
  padding: 22px;
  border-left: 4px solid var(--accent);
  background: #f7f7f7;
  color: var(--text);
  font-size: 17px;
  line-height: 1.8;
}

.article-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.seo-cta {
  padding: 64px 0;
  background: var(--text);
  color: #fff;
}

.seo-cta p {
  max-width: 720px;
  color: rgba(255, 255, 255, 0.72);
}

.feature-card,
.stage-block,
.auth-card,
.access-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 10px 40px rgba(25, 47, 64, 0.04);
}

.feature-card p {
  color: var(--muted);
  margin-bottom: 0;
}

.course-titlebar {
  margin-bottom: 22px;
  display: grid;
  grid-template-columns: minmax(0, 0.7fr) minmax(280px, 0.5fr);
  gap: 32px;
  align-items: end;
}

.course-titlebar h2 {
  margin-bottom: 0;
}

.course-titlebar .eyebrow {
  grid-column: 1 / -1;
  margin-bottom: -12px;
}

.course-titlebar p:not(.eyebrow) {
  margin: 0;
  color: var(--muted);
}

.home-hero {
  padding: 44px 0 58px;
  background:
    linear-gradient(180deg, #f6f6f6 0%, #f2f2f2 100%);
}

.hero-product-grid {
  display: block;
}

.hero-product-grid > *,
.before-after-grid > *,
.route-head > *,
.difference-grid > * {
  min-width: 0;
}

.hero-copy h1 {
  max-width: none;
}

.hero-copy .lead {
  max-width: none;
}

@media (min-width: 901px) {
  .hero-copy h1 {
    font-size: clamp(34px, 3.55vw, 48px);
    white-space: nowrap;
  }

  .hero-copy .lead {
    white-space: nowrap;
  }
}

.product-map {
  min-height: 620px;
  position: relative;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 18px;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.95), rgba(246, 246, 246, 0.88)),
    linear-gradient(90deg, rgba(0, 0, 0, 0.045) 1px, transparent 1px),
    linear-gradient(180deg, rgba(0, 0, 0, 0.045) 1px, transparent 1px);
  background-size: auto, 42px 42px, 42px 42px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.product-map::before,
.product-map::after {
  content: "";
  position: absolute;
  inset: 86px;
  border: 1px solid rgba(0, 0, 0, 0.1);
  border-radius: 26px;
}

.product-map::after {
  inset: 150px;
  border-style: dashed;
}

.product-phone {
  position: relative;
  z-index: 2;
  width: 286px;
  margin: 0;
  padding: 8px;
  border-radius: 28px;
  background: #111;
  box-shadow: 0 24px 70px rgba(20, 28, 24, 0.18);
}

.product-phone img {
  display: block;
  width: 100%;
  border-radius: 20px;
}

.map-note {
  position: absolute;
  z-index: 3;
  min-width: 112px;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.92);
  color: var(--accent-strong);
  font-size: 14px;
  font-weight: 800;
  text-align: center;
  box-shadow: 0 12px 32px rgba(25, 47, 64, 0.08);
}

.note-ui {
  top: 70px;
  left: 48px;
}

.note-api {
  top: 138px;
  right: 48px;
}

.note-db {
  right: 42px;
  bottom: 178px;
}

.note-admin {
  left: 42px;
  bottom: 150px;
}

.note-ops {
  bottom: 94px;
  left: 50%;
  transform: translateX(-50%);
}

.map-core {
  position: absolute;
  z-index: 4;
  left: 26px;
  right: 26px;
  bottom: 18px;
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(12px);
}

.map-core span {
  color: var(--muted);
}

.hero-gallery {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.hero-gallery-head {
  margin-top: 42px;
}

.hero-gallery-head h2 {
  max-width: 900px;
  margin-bottom: 0;
  font-size: clamp(28px, 2.8vw, 42px);
}

.hero-visual-card {
  min-width: 0;
  margin: 0;
  padding: 16px;
  border: 1px solid rgba(214, 224, 226, 0.95);
  border-radius: 22px;
  background:
    radial-gradient(circle at 50% 8%, rgba(215, 168, 79, 0.1), transparent 28%),
    rgba(255, 255, 255, 0.82);
  box-shadow: 0 24px 72px rgba(0, 0, 0, 0.08);
}

.hero-visual-card > img {
  width: 100%;
  aspect-ratio: 9 / 16;
  display: block;
  object-fit: cover;
  overflow: hidden;
  border: 1px solid rgba(218, 225, 226, 0.9);
  border-radius: 18px;
  box-shadow: 0 18px 48px rgba(25, 47, 64, 0.1);
}

.hero-phone-card {
  width: 100%;
  aspect-ratio: 9 / 16;
  padding: 8px;
  border-radius: 34px;
  background: #101416;
  box-shadow: 0 30px 70px rgba(18, 28, 32, 0.22);
  overflow: hidden;
}

.hero-phone-card img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  border-radius: 24px;
  background: #f7f7f7;
}

.diagnosis-section,
.route-section,
.difference-section,
.curriculum-section,
.topic-section,
.faq-section {
  padding: 66px 0;
}

.section-kicker {
  max-width: none;
  margin-bottom: 28px;
}

.section-kicker h2 {
  margin-bottom: 0;
}

.section-kicker p:not(.eyebrow) {
  max-width: none;
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 18px;
}

@media (min-width: 901px) {
  .diagnosis-section .section-kicker h2,
  .diagnosis-section .section-kicker p:not(.eyebrow) {
    white-space: nowrap;
  }
}

.capability-visual {
  position: relative;
  margin: 32px 0 0;
  padding: 14px;
  border: 1px solid rgba(214, 224, 226, 0.95);
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.78);
  box-shadow: 0 24px 72px rgba(25, 47, 64, 0.08);
}

.capability-visual img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: 16px;
}

.visual-callout {
  position: absolute;
  z-index: 2;
  width: 190px;
  padding: 11px 13px;
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.88);
  color: var(--text);
  box-shadow: 0 14px 38px rgba(25, 47, 64, 0.08);
  backdrop-filter: blur(10px);
}

.visual-callout::before,
.visual-callout::after {
  content: "";
  position: absolute;
  pointer-events: none;
}

.visual-callout::before {
  width: var(--line-x);
  height: var(--line-y);
  border-color: rgba(37, 99, 235, 0.42);
  border-style: solid;
  border-width: var(--line-border);
}

.visual-callout::after {
  width: 8px;
  height: 8px;
  border: 2px solid #fff;
  border-radius: 999px;
  background: var(--accent-strong);
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.18);
}

.visual-callout strong,
.visual-callout span {
  display: block;
}

.visual-callout strong {
  font-size: 14px;
  line-height: 1.3;
}

.visual-callout span {
  margin-top: 4px;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.4;
}

.callout-product {
  --line-x: 82px;
  --line-y: 34px;
  --line-border: 1px 0 0 1px;
  left: 34px;
  top: 34px;
}

.callout-product::before {
  left: 116px;
  top: 100%;
}

.callout-product::after {
  left: 194px;
  top: calc(100% + 30px);
}

.callout-api {
  --line-x: 68px;
  --line-y: 42px;
  --line-border: 1px 1px 0 0;
  left: 336px;
  bottom: 52px;
}

.callout-api::before {
  right: 100%;
  bottom: 50%;
}

.callout-api::after {
  right: calc(100% + 64px);
  bottom: calc(50% + 38px);
}

.callout-data {
  --line-x: 72px;
  --line-y: 34px;
  --line-border: 1px 1px 0 0;
  right: 310px;
  top: 40px;
}

.callout-data::before {
  right: 48px;
  top: 100%;
}

.callout-data::after {
  right: 116px;
  top: calc(100% + 30px);
}

.callout-ops {
  --line-x: 92px;
  --line-y: 46px;
  --line-border: 1px 1px 0 0;
  right: 36px;
  bottom: 54px;
}

.callout-ops::before {
  right: 72px;
  bottom: 100%;
}

.callout-ops::after {
  right: 160px;
  bottom: calc(100% + 42px);
}

@media (min-width: 901px) {
  .hero-gallery-head h2,
  .before-after-grid h2,
  .route-head h2,
  .difference-grid h2,
  .course-titlebar h2,
  .course-titlebar p:not(.eyebrow),
  .final-cta h2 {
    white-space: nowrap;
  }

  .stage-head h3,
  .chapter-row span,
  .chapter-row strong,
  .chapter-row em {
    white-space: nowrap;
  }
}

.chain-board {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  position: relative;
}

.chain-board::before {
  content: "";
  position: absolute;
  left: 9%;
  right: 9%;
  top: 88px;
  height: 1px;
  background: var(--line);
}

.chain-board article {
  position: relative;
  z-index: 2;
  min-height: 248px;
  display: grid;
  grid-template-rows: auto 1fr auto auto;
  gap: 14px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface);
  box-shadow: 0 12px 40px rgba(25, 47, 64, 0.04);
}

.chain-board article > span {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: var(--accent-strong);
  color: #fff;
  font-size: 12px;
  font-weight: 800;
}

.chain-board h3,
.chain-board p {
  margin: 0;
}

.chain-board p {
  color: var(--muted);
}

.mini-visual {
  align-self: center;
  min-height: 76px;
  border: 1px solid #dedede;
  border-radius: 10px;
  background: #fafafa;
  padding: 14px;
}

.code-lines i,
.server-box i {
  display: block;
  height: 8px;
  margin: 8px 0;
  border-radius: 99px;
  background: #d5d5d5;
}

.code-lines i:nth-child(2) {
  width: 70%;
}

.code-lines i:nth-child(3) {
  width: 46%;
}

.form-box,
.lock-box,
.server-box {
  display: grid;
  align-content: center;
  gap: 8px;
}

.form-box i {
  height: 11px;
  border-radius: 6px;
  background: #dedede;
}

.form-box b {
  width: 48%;
  height: 18px;
  border-radius: 5px;
  background: var(--accent);
}

.lock-box i {
  width: 38px;
  height: 28px;
  justify-self: center;
  border: 4px solid #d7d7d7;
  border-bottom: 0;
  border-radius: 20px 20px 0 0;
}

.lock-box b {
  width: 72px;
  height: 44px;
  justify-self: center;
  border-radius: 8px;
  background: var(--accent-strong);
}

.server-box i {
  height: 14px;
  margin: 0;
}

.before-after-section {
  padding: 72px 0;
  background: #fff;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.outcome-head {
  margin-bottom: 28px;
}

.outcome-visual {
  margin: 0;
  padding: 14px;
  border: 1px solid rgba(214, 224, 226, 0.95);
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.78);
  box-shadow: 0 24px 72px rgba(25, 47, 64, 0.08);
}

.outcome-visual img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: 16px;
}

.outcome-cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.outcome-cards article {
  min-width: 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fafafa;
}

.outcome-cards span,
.outcome-cards strong,
.outcome-cards p {
  display: block;
}

.outcome-cards span {
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.outcome-cards strong {
  margin-top: 8px;
  font-size: 18px;
  line-height: 1.35;
}

.outcome-cards p {
  margin: 10px 0 0;
  color: var(--muted);
}

.before-after-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  align-items: start;
}

.before-after-table,
.difference-table {
  display: grid;
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  background: var(--surface);
  box-shadow: 0 14px 52px rgba(25, 47, 64, 0.05);
}

.before-after-table {
  grid-template-columns: 110px 1fr 1fr;
}

.before-after-table > *,
.difference-table > * {
  margin: 0;
  padding: 16px 18px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.before-after-table > :nth-child(3n),
.difference-table > :nth-child(4n) {
  border-right: 0;
}

.before-after-table > :nth-last-child(-n + 3),
.difference-table > :nth-last-child(-n + 4) {
  border-bottom: 0;
}

.before-after-table span,
.difference-table span {
  color: var(--accent-strong);
  font-weight: 800;
}

.before-after-table p,
.difference-table p {
  color: var(--muted);
}

.table-head {
  font-weight: 800;
  color: var(--text);
  background: #fafafa;
}

.table-head.strong {
  background: var(--accent-strong);
  color: #fff;
}

.route-head {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  align-items: start;
  margin-bottom: 28px;
}

.route-head p:not(.eyebrow) {
  max-width: none;
  color: var(--muted);
}

.route-canvas {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.route-canvas article {
  min-height: 320px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 16px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--surface);
}

.route-canvas span {
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.route-canvas h3,
.route-canvas p {
  margin: 0;
}

.route-canvas p {
  color: var(--muted);
}

.learning-map {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  padding: 34px 28px 28px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(248, 250, 248, 0.92)),
    linear-gradient(90deg, rgba(0, 0, 0, 0.035) 1px, transparent 1px);
  background-size: auto, 44px 44px;
  box-shadow: var(--shadow);
}

.map-rail {
  position: absolute;
  left: 82px;
  right: 82px;
  top: 64px;
  height: 3px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent-strong), var(--accent), var(--warm));
}

.map-stop {
  position: relative;
  z-index: 2;
  display: grid;
  gap: 18px;
}

.map-stop > span {
  width: 58px;
  height: 58px;
  display: grid;
  place-items: center;
  border: 5px solid #fff;
  border-radius: 999px;
  background: var(--accent-strong);
  color: #fff;
  font-weight: 900;
  box-shadow: 0 12px 32px rgba(25, 47, 64, 0.18);
}

.map-stop div {
  min-height: 156px;
  display: grid;
  align-content: start;
  gap: 12px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.88);
}

.map-stop strong {
  font-size: 23px;
  line-height: 1.2;
}

.map-stop p {
  margin: 0;
  color: var(--muted);
}

.map-stop em {
  justify-self: start;
  padding: 8px 12px;
  border-radius: 999px;
  background: #f1f1f1;
  color: var(--accent-strong);
  font-style: normal;
  font-weight: 800;
}

.map-deliverables {
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin-top: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--line);
}

.map-deliverables div {
  display: grid;
  gap: 4px;
  padding: 16px;
  background: #fff;
}

.map-deliverables b {
  color: var(--accent-strong);
  font-size: 13px;
}

.map-deliverables span {
  color: var(--muted);
}

.stage-preview {
  min-height: 128px;
  border: 1px solid #dedede;
  border-radius: 12px;
  background: #fafafa;
  padding: 14px;
}

.phone-preview {
  display: grid;
  gap: 10px;
}

.phone-preview i {
  display: block;
  border-radius: 8px;
  background: #dedede;
}

.phone-preview i:first-child {
  height: 42px;
  background: #d7d7d7;
}

.phone-preview i:nth-child(2) {
  height: 28px;
}

.phone-preview i:nth-child(3) {
  height: 34px;
  width: 70%;
}

.api-preview {
  display: grid;
  align-content: center;
  gap: 12px;
}

.api-preview b {
  padding: 9px 10px;
  border-radius: 7px;
  background: #f1f1f1;
  color: var(--accent-strong);
  font-size: 12px;
}

.api-preview i {
  height: 1px;
  background: var(--line);
}

.security-preview,
.ops-preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.security-preview i,
.ops-preview i {
  display: grid;
  place-items: center;
  border-radius: 8px;
  background: #f1f1f1;
  color: var(--accent-strong);
  font-style: normal;
  font-weight: 700;
}

.workbench-section {
  padding: 72px 0;
  background: #fff;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.workbench {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr 0.85fr;
  gap: 14px;
  align-items: stretch;
}

.work-card {
  min-height: 270px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--surface);
}

.work-card > span {
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.work-card h3 {
  margin: 18px 0 14px;
  font-size: 28px;
}

.work-card ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
}

.work-card li {
  margin-bottom: 8px;
}

.prompt-card {
  background: #162230;
  color: #fff;
}

.prompt-card > span {
  color: #cfcfcf;
}

.prompt-card pre {
  margin: 22px 0 0;
  white-space: pre-wrap;
  color: rgba(255, 255, 255, 0.82);
  font: 15px/1.8 ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

.check-card {
  display: grid;
  align-content: start;
  gap: 10px;
}

.check-row {
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 9px;
  color: var(--muted);
}

.check-row.done {
  background: #f1f1f1;
  color: var(--accent-strong);
}

.check-row.warn {
  background: #f2f2f2;
  color: #6c5b34;
}

.difference-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  align-items: start;
}

.difference-grid > div:first-child {
  max-width: none;
}

.difference-table {
  grid-template-columns: 96px repeat(3, 1fr);
}

.difference-table strong {
  background: #fafafa;
}

.difference-table strong:last-of-type {
  background: var(--accent-strong);
  color: #fff;
}

.compare-lanes {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.compare-lanes article {
  position: relative;
  display: grid;
  align-content: start;
  gap: 18px;
  min-height: 410px;
  padding: 32px 28px 28px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--surface);
  box-shadow: 0 14px 52px rgba(25, 47, 64, 0.05);
}

.weak-lane {
  background: #f8f9f9 !important;
  color: #5f6870;
  filter: grayscale(0.18);
}

.lane-mark {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  font-size: 28px;
  font-weight: 900;
  line-height: 1;
}

.lane-mark.bad {
  background: #eeeeee;
  color: #8a969d;
}

.lane-mark.good {
  width: 58px;
  height: 58px;
  background: #ffd45d;
  color: #173a5a;
  font-size: 34px;
  box-shadow: 0 12px 30px rgba(215, 168, 79, 0.28);
}

.compare-lanes article > span {
  justify-self: start;
  padding: 6px 10px;
  border-radius: 999px;
  background: #f1f1f1;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.compare-lanes h3 {
  margin: 0;
  font-size: 28px;
}

.compare-lanes p {
  margin: 8px 0 0;
  color: var(--muted);
}

.score-row {
  display: grid;
  gap: 8px;
}

.score-row b {
  color: var(--muted);
  font-size: 13px;
}

.score-row i {
  position: relative;
  height: 12px;
  overflow: hidden;
  border-radius: 999px;
  background: #e5e5e5;
}

.score-row i::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: var(--score);
  border-radius: inherit;
  background: #a8b6bd;
}

.featured-lane {
  border-color: rgba(37, 99, 235, 0.35) !important;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(246, 246, 246, 0.94)),
    linear-gradient(135deg, rgba(255, 212, 93, 0.22), transparent 42%) !important;
  box-shadow: 0 26px 80px rgba(0, 0, 0, 0.12) !important;
}

.featured-lane > span {
  background: var(--accent-strong) !important;
  color: #fff !important;
}

.featured-lane .score-row i::before {
  background: linear-gradient(90deg, var(--accent-strong), var(--accent), var(--warm));
}

.curriculum-section {
  background: #fafafa;
}

.course-entry {
  display: grid;
  grid-template-columns: minmax(0, 0.88fr) minmax(360px, 0.62fr);
  gap: 34px;
  align-items: stretch;
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.96), rgba(246, 246, 246, 0.92)),
    linear-gradient(90deg, rgba(0, 0, 0, 0.035) 1px, transparent 1px);
  background-size: auto, 34px 34px;
  box-shadow: 0 22px 72px rgba(25, 47, 64, 0.07);
}

.course-entry-copy h2 {
  margin-bottom: 12px;
}

.course-entry-copy p:not(.eyebrow) {
  max-width: 760px;
  margin: 0;
  color: var(--muted);
  font-size: 18px;
}

.course-entry-panel {
  display: grid;
  gap: 18px;
  padding: 22px;
  border: 1px solid rgba(214, 224, 226, 0.95);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.86);
}

.course-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
}

.course-stats span {
  min-height: 66px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 12px;
  color: var(--muted);
  font-size: 13px;
  text-align: center;
}

.course-stats strong {
  display: block;
  color: var(--accent-strong);
  font-size: 24px;
  line-height: 1;
}

.course-line {
  display: grid;
  grid-template-columns: auto 1fr auto 1fr auto 1fr auto 1fr auto;
  gap: 8px;
  align-items: center;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.course-line i {
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent-strong), var(--warm));
}

.course-modal-open {
  width: 100%;
  justify-content: center;
}

.course-modal {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: none;
}

.course-modal.open {
  display: block;
}

.course-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(17, 25, 30, 0.42);
  backdrop-filter: blur(10px);
}

.course-modal-panel {
  position: relative;
  z-index: 1;
  width: min(960px, calc(100% - 48px));
  max-height: min(82vh, 820px);
  margin: 8vh auto 0;
  display: grid;
  grid-template-rows: auto 1fr;
  overflow: hidden;
  border: 1px solid rgba(214, 224, 226, 0.95);
  border-radius: 22px;
  background: #fff;
  box-shadow: 0 38px 110px rgba(11, 24, 33, 0.28);
}

.course-modal-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  padding: 24px 28px 18px;
  border-bottom: 1px solid var(--line);
}

.course-modal-head h2 {
  margin: 0;
  font-size: 28px;
}

.modal-close {
  width: 42px;
  height: 42px;
  padding: 0;
  display: grid;
  place-items: center;
  border-radius: 999px;
  font-size: 24px;
  line-height: 1;
}

.course-modal-body {
  overflow: auto;
  padding: 18px 28px 28px;
}

.modal-stage {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  gap: 18px;
  padding: 16px 0;
  border-bottom: 1px solid #eeeeee;
}

.modal-stage:last-child {
  border-bottom: 0;
}

.modal-stage-head {
  position: sticky;
  top: 0;
  align-self: start;
}

.modal-stage-head span {
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.modal-stage-head h3 {
  margin: 6px 0 0;
  font-size: 22px;
}

.modal-chapters {
  display: grid;
  gap: 8px;
}

.modal-chapter {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr) minmax(180px, 0.5fr) 84px;
  gap: 14px;
  align-items: center;
  min-height: 54px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fafafa;
}

.modal-chapter span {
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.modal-chapter strong {
  font-size: 15px;
}

.modal-chapter em {
  color: var(--muted);
  font-size: 13px;
  font-style: normal;
}

.modal-chapter b {
  padding: 7px 10px;
  border-radius: 8px;
  background: var(--accent-strong);
  color: #fff;
  font-size: 13px;
  text-align: center;
}

body.modal-open {
  overflow: hidden;
}

.stage-block {
  margin-bottom: 12px;
}

.stage-head {
  display: block;
  border-bottom: 1px solid var(--line);
  padding-bottom: 10px;
  margin-bottom: 6px;
}

.stage-head span {
  color: var(--muted);
  font-size: 13px;
}

.stage-head h3 {
  margin: 0;
}

.chapter-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}

.chapter-list.compact {
  grid-template-columns: 1fr;
}

.chapter-row {
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr) minmax(190px, 0.48fr);
  align-items: center;
  gap: 16px;
  min-height: 58px;
  padding: 10px 14px;
  border-radius: 6px;
  border: 1px solid transparent;
  border-bottom-color: #eeeeee;
}

.chapter-row:hover {
  background: var(--surface-soft);
  border-color: var(--line);
}

.chapter-row span {
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 700;
}

.chapter-row strong {
  font-size: 15px;
}

.chapter-row em {
  color: var(--muted);
  font-size: 13px;
  font-style: normal;
  text-align: right;
}

.auth-page {
  min-height: calc(100vh - 72px);
  display: grid;
  place-items: center;
  padding: 56px 20px;
}

.auth-layout {
  width: min(520px, 100%);
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.auth-card h1 {
  font-size: 38px;
  margin-bottom: 28px;
}

.form-field {
  display: grid;
  gap: 8px;
  margin-bottom: 16px;
}

.form-field label {
  font-weight: 700;
}

.form-field input {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0 14px;
  font: inherit;
}

.code-row {
  display: grid;
  grid-template-columns: 1fr 130px;
  gap: 10px;
}

.form-message {
  min-height: 24px;
  color: var(--muted);
}

.form-message.success {
  color: var(--accent-strong);
}

.form-message.error {
  color: #a64747;
}

.dashboard-top {
  padding: 48px 0 24px;
}

.system-map-section {
  padding: 54px 0 72px;
}

.system-map-section .section-shell {
  width: min(1500px, calc(100% - 32px));
}

.system-map-board {
  border: 1px solid rgba(217, 217, 210, 0.92);
  background: rgba(255, 255, 255, 0.68);
  box-shadow: 0 28px 100px rgba(21, 21, 21, 0.06);
}

.map-board-head {
  padding: 34px 30px 28px;
  border-bottom: 1px solid var(--line);
}

.map-board-head h2 {
  margin: 0;
  font-size: clamp(34px, 4.4vw, 58px);
  line-height: 1.04;
  letter-spacing: -0.04em;
  white-space: nowrap;
}

.system-map-canvas {
  position: relative;
  display: grid;
  grid-template-columns: 260px minmax(820px, 1fr) 260px;
  gap: 34px;
  align-items: stretch;
  overflow: visible;
  padding: 22px 28px 34px;
  background: #f6f6f6;
}

.system-map-image {
  position: relative;
  z-index: 1;
  min-width: 0;
  margin: 0;
  border: 1px solid rgba(217, 217, 210, 0.9);
  background: #fff;
  overflow: hidden;
}

.system-map-image > img {
  display: block;
  width: 100%;
  height: 100%;
  min-height: 720px;
  object-fit: contain;
}

.system-map-rail {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 10px;
  min-width: 0;
}

.system-map-rail.left {
  align-items: flex-end;
}

.system-map-rail.right {
  align-items: flex-start;
}

.system-map-rail.bottom {
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: repeat(11, minmax(0, 1fr));
  gap: 10px;
  align-items: stretch;
  padding-top: 18px;
}

.system-map-node {
  position: relative;
  width: 100%;
  min-height: 76px;
  display: grid;
  gap: 4px;
  padding: 12px 14px;
  border: 1.5px solid rgba(37, 99, 235, 0.64);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.95);
  color: var(--text);
  text-align: left;
  box-shadow: 0 16px 38px rgba(37, 99, 235, 0.1);
  backdrop-filter: blur(12px);
  transition: transform 160ms ease, border-color 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.system-map-node::after {
  content: "";
  position: absolute;
  top: 50%;
  width: 34px;
  border-top: 2px dashed rgba(37, 99, 235, 0.82);
  transform: translateY(-50%);
  pointer-events: none;
}

.system-map-node::before {
  content: "";
  position: absolute;
  top: 50%;
  width: 8px;
  height: 8px;
  border: 2px solid rgba(37, 99, 235, 0.9);
  border-radius: 50%;
  background: #f6f6f6;
  transform: translateY(-50%);
  pointer-events: none;
}

.system-map-rail.left .system-map-node::after {
  right: -34px;
}

.system-map-rail.left .system-map-node::before {
  right: -45px;
}

.system-map-rail.right .system-map-node::after {
  left: -34px;
}

.system-map-rail.right .system-map-node::before {
  left: -45px;
}

.system-map-rail.bottom .system-map-node::after {
  top: -18px;
  left: 50%;
  width: 0;
  height: 18px;
  border-top: 0;
  border-left: 2px dashed rgba(37, 99, 235, 0.82);
  transform: translateX(-50%);
}

.system-map-rail.bottom .system-map-node::before {
  top: -28px;
  left: 50%;
  transform: translateX(-50%);
}

.system-map-node:hover {
  transform: translateY(-2px);
  border-color: rgba(37, 99, 235, 0.9);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 22px 52px rgba(37, 99, 235, 0.16);
}

.system-map-node.current {
  border-color: rgba(223, 169, 48, 0.98);
  box-shadow: 0 28px 72px rgba(168, 112, 24, 0.18);
}

.system-map-node.current::after {
  border-top-color: rgba(215, 168, 79, 0.92);
  border-left-color: rgba(215, 168, 79, 0.92);
}

.system-map-node.current::before {
  border-color: rgba(215, 168, 79, 0.98);
}

.system-map-node span {
  color: var(--accent-strong);
  font-family: "SF Mono", Monaco, Consolas, monospace;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.04em;
}

.system-map-node strong {
  color: var(--text);
  font-size: 14px;
  line-height: 1.28;
}

.system-map-node em {
  color: var(--muted);
  font-size: 11px;
  font-style: normal;
  line-height: 1.45;
}

.system-map-extra {
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(0, 2fr);
  gap: 24px;
  align-items: stretch;
  padding: 22px 28px 30px;
  border-top: 1px solid var(--line);
  background: #fff;
}

.system-map-extra > div:first-child {
  display: grid;
  align-content: center;
  padding: 20px 22px;
  border: 1px solid rgba(217, 217, 210, 0.9);
  background: #fafafa;
}

.system-map-extra strong {
  color: var(--text);
  font-size: clamp(22px, 2.4vw, 34px);
  line-height: 1.08;
}

.system-map-rail.extra {
  display: block;
}

.system-map-rail.extra .system-map-node {
  min-height: 100%;
  border-color: rgba(223, 169, 48, 0.95);
  background: linear-gradient(135deg, #ffffff 0%, #fffaf0 100%);
  box-shadow: 0 22px 56px rgba(168, 112, 24, 0.13);
}

.system-map-rail.extra .system-map-node::before,
.system-map-rail.extra .system-map-node::after {
  display: none;
}

.reader-layout {
  display: grid;
  grid-template-columns: 300px minmax(0, 1fr);
  min-height: calc(100vh - 72px);
}

.reader-sidebar {
  border-right: 1px solid var(--line);
  background: #fafafa;
  padding: 22px;
  position: sticky;
  top: 72px;
  height: calc(100vh - 72px);
  overflow: auto;
}

.reader-nav {
  display: grid;
  gap: 6px;
}

.reader-nav a {
  border-radius: 8px;
  padding: 10px;
  color: var(--muted);
  display: grid;
  gap: 2px;
}

.reader-nav a span {
  font-size: 12px;
}

.reader-nav a.active {
  background: var(--surface-soft);
  color: var(--text);
}

.reader-main {
  padding: 34px min(5vw, 64px);
}

.lesson-article {
  max-width: 960px;
  margin: 0 auto;
  user-select: none;
  position: relative;
}

.reader-watermark {
  position: fixed;
  right: 26px;
  bottom: 22px;
  opacity: 0.18;
  pointer-events: none;
  font-size: 13px;
}

.lesson-hero {
  padding: 10px 0 40px;
  border-bottom: 1px solid var(--line);
}

.lesson-hero h1 {
  max-width: 980px;
  font-size: clamp(40px, 5vw, 72px);
  line-height: 1.05;
  letter-spacing: -0.05em;
}

.lesson-hero p {
  max-width: 860px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.85;
}

.lesson-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: 28px 0;
}

.lesson-grid div {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 18px;
}

.lesson-grid span {
  color: var(--muted);
  font-size: 13px;
  display: block;
  margin-bottom: 8px;
}

.lesson-section {
  display: block;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 28px 30px;
  margin: 24px 0;
  box-shadow: 0 18px 54px rgba(15, 23, 42, 0.04);
}

.lesson-section h2 {
  margin: 0 0 16px;
  font-size: clamp(24px, 2.4vw, 34px);
  line-height: 1.18;
  letter-spacing: -0.02em;
}

.lesson-section > :not(h2) {
  grid-column: auto;
}

.lesson-section p {
  color: var(--muted);
  line-height: 1.9;
  margin: 12px 0;
}

.lesson-section li {
  margin-bottom: 10px;
  color: var(--muted);
  line-height: 1.8;
}

.lesson-lead {
  background: #f7f7f7;
}

.lesson-lead li:first-child {
  color: var(--text);
  font-weight: 700;
}

.lesson-two-col {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  gap: 18px;
  align-items: stretch;
}

.lesson-two-col .lesson-section {
  margin: 0;
}

.prompt-card {
  background: #151515;
  color: #f7f7f7;
}

.prompt-card h2 {
  color: #f7f7f7;
}

.prompt-card pre {
  white-space: pre-wrap;
  margin: 0;
  font: 15px/1.8 "SF Mono", Monaco, Consolas, monospace;
  color: #eeeeee;
}

.next-bridge {
  border-color: rgba(37, 99, 235, 0.22);
}

.course-figure {
  background: #f7f7f7;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 24px;
  margin: 24px 0;
}

.course-figure h2 {
  font-size: 22px;
  margin-bottom: 18px;
}

.course-image-figure {
  grid-column: 1 / -1;
  margin: 28px 0 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: #f6f6f6;
  box-shadow: none;
}

.course-image-figure img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  cursor: zoom-in;
}

.course-image-figure figcaption {
  padding: 14px 18px 16px;
  color: var(--muted);
  line-height: 1.7;
  border-top: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.76);
}

.lesson-section > .course-image-figure {
  grid-column: auto;
  margin-top: 20px;
}

.image-lightbox-open {
  overflow: hidden;
}

.image-lightbox {
  position: fixed;
  inset: 0;
  z-index: 2147483000;
  display: grid;
  place-items: center;
  padding: 28px;
  isolation: isolate;
  pointer-events: auto;
}

.image-lightbox-open .map-reader-modal.open,
.image-lightbox-open .course-modal.open {
  pointer-events: none;
}

.image-lightbox-backdrop {
  position: absolute;
  inset: 0;
  border: 0;
  border-radius: 0;
  background: rgba(11, 18, 24, 0.72);
  backdrop-filter: blur(12px);
  cursor: zoom-out;
}

.image-lightbox-panel {
  position: relative;
  z-index: 1;
  width: min(1180px, 96vw);
  margin: 0;
  border-radius: 18px;
  overflow: hidden;
  background: #fff;
  box-shadow: 0 28px 80px rgba(0, 0, 0, 0.32);
}

.image-lightbox-panel img {
  display: block;
  width: 100%;
  max-height: 88vh;
  object-fit: contain;
  background: #f6f6f6;
}

.image-lightbox-close {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 2;
  width: 42px;
  min-height: 42px;
  padding: 0;
  border-radius: 50%;
  border-color: rgba(255, 255, 255, 0.7);
  background: rgba(255, 255, 255, 0.86);
  font-size: 26px;
  line-height: 1;
}

.metro-figure {
  background:
    linear-gradient(90deg, rgba(0, 0, 0, 0.035) 1px, transparent 1px),
    linear-gradient(180deg, rgba(0, 0, 0, 0.035) 1px, transparent 1px),
    #f8f8f8;
  background-size: 34px 34px;
  overflow: hidden;
}

.metro-map {
  display: grid;
  grid-template-columns: repeat(6, minmax(112px, 1fr));
  gap: 0;
  position: relative;
  padding: 30px 0 18px;
}

.metro-map::before {
  content: "";
  position: absolute;
  left: 7%;
  right: 7%;
  top: 54px;
  height: 8px;
  border-radius: 999px;
  background: linear-gradient(90deg, #111827, #2563eb 58%, #d8a436);
  box-shadow: 0 12px 26px rgba(0, 0, 0, 0.12);
}

.metro-stop {
  position: relative;
  z-index: 1;
  display: grid;
  justify-items: center;
  align-content: start;
  gap: 10px;
  text-align: center;
}

.metro-stop span {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  border: 7px solid #f8f8f8;
  border-radius: 50%;
  background: #111827;
  color: #fff;
  font-weight: 900;
  font-size: 13px;
  box-shadow: 0 10px 22px rgba(0, 0, 0, 0.14);
}

.metro-stop:nth-child(n + 4) span {
  background: #2563eb;
}

.metro-stop:last-child span {
  background: #d8a436;
  color: #1b2024;
}

.metro-stop strong {
  font-size: 17px;
}

.metro-stop small {
  width: min(120px, 100%);
  color: var(--muted);
  line-height: 1.45;
}

.course-journey,
.course-workspace,
.inline-figure {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.course-journey div,
.course-workspace div,
.inline-figure div {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 18px;
  min-width: 110px;
  text-align: center;
  font-weight: 700;
}

.course-journey span::before {
  content: "→";
  color: var(--accent-strong);
}

.course-journey span:last-child {
  display: none;
}

.course-workspace {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}

.course-workspace small,
.inline-figure small,
.figure-caption {
  display: block;
  color: var(--muted);
  font-weight: 400;
}

.course-phone-map {
  display: grid;
  place-items: center;
}

.phone-shell-mini {
  width: min(280px, 100%);
  min-height: 460px;
  border: 10px solid #1b2024;
  border-radius: 34px;
  background: #f7f7f7;
  padding: 74px 20px 20px;
  display: grid;
  gap: 12px;
  align-content: start;
  position: relative;
}

.phone-shell-mini::before {
  content: "";
  position: absolute;
  top: 20px;
  left: 50%;
  width: 82px;
  height: 22px;
  border-radius: 999px;
  background: #111;
  transform: translateX(-50%);
}

.phone-shell-mini span {
  background: #fff;
  border: 1px solid #eadfc7;
  border-radius: 14px;
  padding: 16px;
  font-weight: 700;
  text-align: center;
}

.inline-figure {
  margin: 20px 0 8px;
}

.product-overview-figure {
  display: grid;
  grid-template-columns: 1fr 1.15fr 1fr;
  grid-template-areas:
    "customer core owner"
    ". system .";
  gap: 16px;
  align-items: center;
  margin: 22px 0 10px;
  position: relative;
}

.product-overview-figure::before,
.product-overview-figure::after {
  content: "";
  position: absolute;
  top: 54px;
  height: 2px;
  background: linear-gradient(90deg, transparent, rgba(37, 99, 235, 0.35), transparent);
  pointer-events: none;
}

.product-overview-figure::before {
  left: 26%;
  right: 50%;
}

.product-overview-figure::after {
  left: 50%;
  right: 26%;
}

.product-role,
.product-core {
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fff;
  padding: 20px;
  text-align: center;
  box-shadow: 0 18px 36px rgba(0, 0, 0, 0.06);
}

.product-role.customer {
  grid-area: customer;
}

.product-role.owner {
  grid-area: owner;
}

.product-role.system {
  grid-area: system;
}

.product-core {
  grid-area: core;
  min-height: 132px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, #111827, #2563eb);
  color: #fff;
}

.product-role span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 52px;
  height: 28px;
  padding: 0 10px;
  border-radius: 999px;
  background: #f1f1f1;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.product-role strong,
.product-core strong {
  display: block;
  margin-top: 12px;
  font-size: 20px;
}

.product-role small,
.product-core span {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  line-height: 1.5;
}

.product-core span {
  color: rgba(255, 255, 255, 0.78);
}

.course-table-wrap {
  overflow: auto;
  margin-top: 22px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  border-radius: 0;
  background: transparent;
}

.course-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 620px;
}

.course-table th,
.course-table td {
  padding: 16px 8px;
  border-bottom: 1px solid rgba(217, 217, 210, 0.9);
  text-align: left;
  vertical-align: top;
}

.course-table th {
  background: transparent;
  color: var(--accent-strong);
  font-family: "SF Mono", Monaco, Consolas, monospace;
  font-size: 12px;
  letter-spacing: 0.04em;
}

.course-table td {
  color: var(--muted);
  line-height: 1.65;
}

.course-table td:first-child {
  color: var(--text);
  font-weight: 800;
  white-space: nowrap;
}

.course-table tr:last-child td {
  border-bottom: 0;
}

.system-layers-figure {
  display: grid;
  grid-template-columns: minmax(240px, 0.72fr) 1.28fr;
  gap: 22px;
  margin: 24px 0 12px;
  align-items: center;
}

.layer-phone {
  width: min(270px, 100%);
  aspect-ratio: 9 / 19.5;
  justify-self: center;
  border: 10px solid #1b2024;
  border-radius: 38px;
  background:
    linear-gradient(#fff 0 0) padding-box,
    linear-gradient(135deg, #f7f7f7, #f1f1f1) border-box;
  padding: 76px 22px 24px;
  position: relative;
  display: grid;
  align-content: start;
  gap: 16px;
  box-shadow: 0 22px 44px rgba(0, 0, 0, 0.08);
}

.layer-phone::before {
  content: "";
  position: absolute;
  top: 22px;
  left: 50%;
  width: 86px;
  height: 22px;
  border-radius: 999px;
  background: #111;
  transform: translateX(-50%);
}

.layer-phone span,
.layer-stack span {
  display: inline-flex;
  width: fit-content;
  border-radius: 999px;
  padding: 5px 10px;
  background: #f1f1f1;
  color: var(--accent-strong);
  font-size: 12px;
  font-weight: 800;
}

.layer-phone strong {
  font-size: 26px;
}

.layer-phone small {
  color: var(--muted);
  line-height: 1.6;
}

.layer-stack {
  display: grid;
  gap: 14px;
  position: relative;
}

.layer-stack::before {
  content: "";
  position: absolute;
  left: 27px;
  top: 42px;
  bottom: 42px;
  width: 4px;
  border-radius: 999px;
  background: linear-gradient(#111827, #2563eb, #d8a436);
}

.layer-stack div {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    "badge title"
    "badge desc";
  column-gap: 16px;
  align-content: center;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 22px;
  background: #fff;
  box-shadow: 0 16px 34px rgba(0, 0, 0, 0.06);
}

.layer-stack span {
  grid-area: badge;
  width: 56px;
  height: 56px;
  justify-content: center;
  align-items: center;
  background: #111827;
  color: #fff;
}

.layer-stack div:nth-child(2) span {
  background: #2563eb;
}

.layer-stack div:nth-child(3) span {
  background: #d8a436;
  color: #1b2024;
}

.layer-stack strong {
  grid-area: title;
  font-size: 21px;
}

.layer-stack small {
  grid-area: desc;
  color: var(--muted);
  margin-top: 6px;
  line-height: 1.5;
}

.inline-figure.files {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}

.inline-figure.wireframe {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  background: #f1f1f1;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 18px;
}

.inline-figure.wireframe div {
  min-height: 92px;
  background: #fff;
}

.inline-figure.wireframe .wide {
  grid-column: 1 / -1;
}

.inline-figure.wireframe .short {
  min-height: 54px;
}

.lesson-note {
  margin-top: 18px;
  background: #f7f7f7;
  border: 1px solid #ecdca6;
  border-radius: 12px;
  padding: 16px;
  color: #6d5512;
}

.prompt-compare {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 14px;
  margin-top: 18px;
}

.prompt-compare div {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
  background: #fff;
}

.prompt-compare div:first-child {
  background: #f4f4f4;
  color: var(--muted);
}

.prompt-compare span {
  display: block;
  font-weight: 800;
  color: var(--accent-strong);
  margin-bottom: 8px;
}

.clarity-figure {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.clarity-card {
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 22px;
  background: #fff;
  min-height: 250px;
  box-shadow: 0 18px 48px rgba(0, 0, 0, 0.06);
}

.clarity-card.muted {
  background: #f5f5f5;
  color: #666;
}

.clarity-card.strong {
  border-color: rgba(37, 99, 235, 0.2);
  background: linear-gradient(145deg, #ffffff, #f5f5f5);
}

.clarity-card span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 30px;
  padding: 0 12px;
  border-radius: 999px;
  background: #eeeeee;
  color: var(--accent-strong);
  font-size: 0.82rem;
  font-weight: 900;
}

.clarity-card.muted span {
  background: #e9e9e9;
  color: #666;
}

.clarity-card strong {
  display: block;
  margin-top: 18px;
  color: var(--ink);
  font-size: clamp(1.25rem, 2vw, 1.8rem);
  line-height: 1.25;
}

.clarity-card p {
  margin-top: 12px;
}

.clarity-card ul {
  display: grid;
  gap: 9px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.clarity-card li {
  margin: 0;
  color: var(--muted);
}

.clarity-card li::before {
  content: "";
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-right: 8px;
  border-radius: 999px;
  background: #d6d6d6;
  vertical-align: 2px;
}

.clarity-card.strong li::before {
  background: var(--accent-strong);
}

.click-chain-figure {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  align-items: stretch;
  gap: 10px;
  margin-top: 22px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background:
    linear-gradient(90deg, rgba(0, 0, 0, 0.035), transparent 45%, rgba(208, 148, 35, 0.08)),
    #fff;
}

.chain-node {
  min-height: 152px;
  border: 1px solid rgba(222, 222, 222, 0.95);
  border-radius: 16px;
  padding: 16px;
  background: rgba(255, 255, 255, 0.9);
}

.chain-node span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 999px;
  background: var(--accent-strong);
  color: #fff;
  font-weight: 900;
  font-size: 0.78rem;
}

.chain-node strong {
  display: block;
  margin-top: 16px;
  color: var(--ink);
  font-size: 1.05rem;
}

.chain-node small {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  line-height: 1.65;
}

.click-chain-figure i {
  display: none;
}

.form-fields-figure {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 22px;
}

.form-field-card {
  position: relative;
  min-height: 210px;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 20px;
  background:
    linear-gradient(180deg, rgba(246, 246, 246, 0.82), rgba(255, 255, 255, 0.96)),
    #fff;
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.06);
}

.form-field-card span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 999px;
  background: var(--accent-strong);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 900;
}

.form-field-card strong {
  display: block;
  margin-top: 18px;
  color: var(--ink);
  font-size: 1.18rem;
}

.form-field-card p {
  margin-top: 10px;
  color: var(--muted);
}

.form-field-card small {
  display: block;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid rgba(222, 222, 222, 0.8);
  color: #555;
  line-height: 1.65;
}

.frontend-backend-figure {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 96px minmax(0, 1fr);
  gap: 18px;
  align-items: stretch;
  margin-top: 22px;
}

.frontend-backend-figure::before {
  content: "API";
  grid-column: 2;
  grid-row: 1;
  align-self: center;
  justify-self: center;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 74px;
  height: 74px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent-strong), #d49a2a);
  color: #fff;
  font-weight: 900;
  box-shadow: 0 18px 42px rgba(37, 99, 235, 0.14);
}

.fb-lane {
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 24px;
  background: #fff;
  box-shadow: 0 20px 54px rgba(0, 0, 0, 0.06);
}

.fb-lane.frontend {
  grid-column: 1;
}

.fb-lane.backend {
  grid-column: 3;
  background: linear-gradient(145deg, #ffffff, #f5f5f5);
  border-color: rgba(37, 99, 235, 0.18);
}

.fb-lane span {
  display: inline-flex;
  height: 30px;
  align-items: center;
  padding: 0 12px;
  border-radius: 999px;
  background: #eeeeee;
  color: var(--accent-strong);
  font-size: 0.82rem;
  font-weight: 900;
}

.fb-lane strong {
  display: block;
  margin-top: 16px;
  color: var(--ink);
  font-size: clamp(1.35rem, 2vw, 2rem);
}

.fb-lane ul {
  display: grid;
  gap: 12px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.fb-lane li {
  margin: 0;
  color: var(--muted);
}

.fb-lane li::before {
  content: "";
  display: inline-block;
  width: 8px;
  height: 8px;
  margin-right: 8px;
  border-radius: 999px;
  background: var(--accent-strong);
  vertical-align: 2px;
}

.rule-cards-figure {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 22px;
}

.rule-card {
  min-height: 184px;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 20px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.95), rgba(246, 246, 246, 0.92)),
    #fff;
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.06);
}

.rule-card span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 30px;
  min-width: 42px;
  padding: 0 10px;
  border-radius: 999px;
  background: var(--accent-strong);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 900;
}

.rule-card strong {
  display: block;
  margin-top: 16px;
  color: var(--ink);
  font-size: 1.12rem;
}

.rule-card p {
  margin-top: 10px;
  color: var(--muted);
}

.lesson-prompt {
  margin-top: 18px;
  border-radius: 12px;
  padding: 18px;
}

.checkpoint {
  background: #f7f7f7;
}

.visual-panel {
  border-radius: 14px;
  padding: 28px;
  background: linear-gradient(135deg, #f1f1f1, #f5f5f5);
  border: 1px solid var(--line);
  margin: 24px 0;
}

.flow-visual,
.network-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.flow-visual div,
.network-visual div,
.stack-visual div,
.ops-visual div,
.shield {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 18px 22px;
  text-align: center;
  min-width: 120px;
}

.flow-visual span,
.network-visual span {
  color: var(--accent-strong);
}

.flow-visual span::before {
  content: "→";
}

.network-visual span::before {
  content: "→ ";
}

.phone-visual {
  width: 240px;
  margin: 0 auto;
  border: 1px solid var(--line);
  border-radius: 28px;
  padding: 14px;
  background: #fff;
}

.phone-screen {
  border-radius: 20px;
  min-height: 260px;
  background: #f1f1f1;
  padding: 28px 18px;
}

.phone-screen button {
  margin-top: 30px;
  width: 100%;
  background: var(--accent-strong);
  color: white;
}

.stack-visual,
.ops-visual,
.security-visual {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.ops-visual {
  grid-template-columns: repeat(4, 1fr);
}

.stack-visual span,
.ops-visual small {
  display: block;
  color: var(--muted);
}

.shield {
  border-radius: 40px 40px 12px 12px;
  font-weight: 700;
}

.shield.muted {
  background: var(--surface-soft);
}

.reader-footer {
  max-width: 860px;
  margin: 28px auto 0;
  display: flex;
  justify-content: space-between;
}

.map-reader-open {
  overflow: hidden;
}

.map-reader-modal {
  position: fixed;
  inset: 0;
  z-index: 90;
  display: none;
}

.map-reader-modal.open {
  display: block;
}

.map-reader-backdrop {
  position: absolute;
  inset: 0;
  width: 100%;
  min-height: 100%;
  border: 0;
  border-radius: 0;
  background: rgba(246, 246, 246, 0.78);
  backdrop-filter: blur(16px);
}

.map-reader-panel {
  position: absolute;
  inset: 28px;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  border: 1px solid rgba(189, 189, 180, 0.9);
  background: rgba(250, 250, 250, 0.96);
  box-shadow: 0 40px 120px rgba(21, 21, 21, 0.2);
}

.map-reader-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 22px 28px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.48);
}

.map-reader-head span {
  color: var(--accent-strong);
  font-family: "SF Mono", Monaco, Consolas, monospace;
  font-size: 12px;
  letter-spacing: 0.04em;
}

.map-reader-head h2 {
  margin: 6px 0 0;
  font-size: clamp(22px, 3vw, 34px);
  letter-spacing: -0.035em;
}

.map-reader-close {
  border-radius: 0;
  min-height: 38px;
  background: transparent;
}

.map-reader-body {
  overflow: auto;
  padding: 48px min(6vw, 78px);
}

.map-reader-footer {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  padding: 18px 28px;
  border-top: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.5);
}

.map-reader-footer button:disabled {
  opacity: 0.32;
  cursor: default;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 34px 0 38px;
  background: #f6f6f6;
  color: var(--muted);
}

.company-footer {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 180px;
  gap: 40px;
  align-items: center;
}

.company-footer-info {
  display: grid;
  gap: 7px;
  max-width: 920px;
  color: #555;
  font-size: 13px;
  line-height: 1.7;
}

.company-footer-info strong {
  color: #222;
  font-weight: 700;
}

.company-footer-info a {
  color: #2563eb;
}

.company-footer-logo {
  justify-self: end;
  width: 150px;
  height: auto;
  opacity: 0.94;
}

@media (max-width: 1280px) {
  .system-map-canvas {
    grid-template-columns: 200px minmax(620px, 1fr) 200px;
    gap: 26px;
    padding-inline: 22px;
  }

  .system-map-image > img {
    min-height: 640px;
  }

  .system-map-rail.bottom {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .system-map-node::after {
    width: 26px;
  }

  .system-map-rail.left .system-map-node::after {
    right: -26px;
  }

  .system-map-rail.left .system-map-node::before {
    right: -37px;
  }

  .system-map-rail.right .system-map-node::after {
    left: -26px;
  }

  .system-map-rail.right .system-map-node::before {
    left: -37px;
  }
}

@media (max-width: 900px) {
  .hero-grid,
  .hero-product-grid,
  .auth-layout,
  .reader-layout,
  .split-list,
  .before-after-grid,
  .course-entry,
  .route-head,
  .difference-grid,
  .value-grid,
  .course-titlebar {
    grid-template-columns: 1fr;
  }

  .reader-sidebar {
    position: static;
    height: auto;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .company-footer {
    grid-template-columns: 1fr;
    gap: 22px;
  }

  .company-footer-logo {
    justify-self: start;
    width: 128px;
  }

  .map-board-head {
    grid-template-columns: 1fr;
    gap: 22px;
  }

  .map-board-head h2 {
    white-space: normal;
  }

  .topic-grid,
  .seo-grid,
  .article-topic-list,
  .article-flow,
  .faq-grid {
    grid-template-columns: 1fr;
  }

  .system-map-canvas {
    grid-template-columns: 1fr;
    padding: 12px;
  }

  .system-map-image {
    order: 1;
  }

  .system-map-image > img {
    min-height: 520px;
  }

  .system-map-rail {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: stretch;
  }

  .system-map-rail.left {
    order: 2;
    align-items: stretch;
  }

  .system-map-rail.right {
    order: 3;
    align-items: stretch;
  }

  .system-map-rail.bottom {
    order: 4;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    padding-top: 0;
  }

  .system-map-node {
    width: 100%;
    min-height: 94px;
    padding: 12px;
  }

  .system-map-node::before,
  .system-map-node::after {
    display: none;
  }

  .system-map-extra {
    grid-template-columns: 1fr;
    padding: 12px;
  }

  .map-reader-panel {
    inset: 12px;
  }

  .map-reader-body {
    padding: 28px 18px;
  }

  .feature-grid,
  .chain-board,
  .hero-gallery,
  .outcome-cards,
  .route-canvas,
  .learning-map,
  .map-deliverables,
  .workbench,
  .compare-lanes,
  .promise-grid,
  .compare-table,
  .outcome-grid,
  .chapter-list,
  .lesson-grid,
  .lesson-two-col,
  .metro-map,
  .course-workspace,
  .inline-figure.files,
  .product-overview-figure,
  .system-layers-figure,
  .prompt-compare,
  .clarity-figure,
  .click-chain-figure,
  .form-fields-figure,
  .frontend-backend-figure,
  .rule-cards-figure,
  .stack-visual,
  .ops-visual,
  .security-visual {
    grid-template-columns: 1fr;
  }

  .frontend-backend-figure::before {
    grid-column: 1;
    grid-row: auto;
    width: 64px;
    height: 64px;
  }

  .fb-lane.frontend,
  .fb-lane.backend {
    grid-column: 1;
  }

  .hero-proof {
    grid-template-columns: 1fr;
  }

  .visual-callout {
    display: none;
  }

  .product-map {
    min-height: 560px;
  }

  .chain-board::before {
    display: none;
  }

  .map-rail {
    left: 57px;
    right: auto;
    top: 48px;
    bottom: 174px;
    width: 3px;
    height: auto;
    background: linear-gradient(180deg, var(--accent-strong), var(--accent), var(--warm));
  }

  .before-after-table,
  .difference-table {
    width: 100%;
    min-width: 0;
  }

  .course-modal-panel {
    width: min(100% - 24px, 760px);
  }

  .modal-stage {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .modal-stage-head {
    position: static;
  }

  .process-line {
    grid-template-columns: repeat(3, 1fr);
  }

  .method-note {
    text-align: left;
  }

  .chapter-row {
    grid-template-columns: 62px minmax(0, 1fr);
  }

  .chapter-row em {
    grid-column: 2;
    text-align: left;
  }

  .section-intro {
    display: block;
  }

  .nav-links {
    gap: 6px;
  }
}

@media (max-width: 560px) {
  .nav-shell,
  .section-shell,
  .footer-shell {
    width: min(calc(100% - 24px), 390px);
  }

  .nav-links a:not(.mobile-keep) {
    display: none;
  }

  .nav-links .button.primary {
    display: none;
  }

  .hero {
    padding-top: 42px;
  }

  .home-hero {
    padding-top: 44px;
  }

  h1 {
    font-size: 34px;
    overflow-wrap: normal;
  }

  h2 {
    font-size: 28px;
    overflow-wrap: normal;
  }

  .lead {
    font-size: 17px;
    overflow-wrap: anywhere;
  }

  .hero-grid {
    gap: 28px;
  }

  .hero-product-grid {
    gap: 30px;
  }

  .hero-copy h1,
  .hero-copy .lead,
  .section-kicker,
  .route-head,
  .difference-grid,
  .before-after-grid {
    max-width: 100%;
  }

  .hero-copy .lead {
    max-width: 300px;
  }

  .hero-gallery {
    max-width: 320px;
    margin-top: 30px;
  }

  .course-entry {
    padding: 20px;
  }

  .course-entry-panel {
    padding: 16px;
  }

  .course-stats {
    grid-template-columns: 1fr;
  }

  .course-line {
    grid-template-columns: 1fr;
  }

  .course-line i {
    display: none;
  }

  .course-modal-panel {
    width: 100%;
    max-height: 92vh;
    margin: 8vh 0 0;
    border-radius: 22px 22px 0 0;
  }

  .course-modal-head {
    padding: 20px 18px 14px;
  }

  .course-modal-head h2 {
    font-size: 22px;
  }

  .course-modal-body {
    padding: 14px 18px 22px;
  }

  .modal-chapter {
    grid-template-columns: 56px minmax(0, 1fr);
  }

  .modal-chapter em,
  .modal-chapter b {
    grid-column: 2;
  }

  .hero-visual-card {
    padding: 16px;
  }

  .hero-visual-card figcaption {
    min-height: auto;
  }

  .home-hero,
  .diagnosis-section,
  .route-section,
  .difference-section,
  .curriculum-section,
  .before-after-section,
  .workbench-section {
    padding-left: 0;
    padding-right: 0;
  }

  .product-map {
    min-height: 490px;
    border-radius: 14px;
  }

  .product-map::before,
  .product-map::after {
    inset: 58px 22px;
  }

  .product-map::after {
    inset: 104px 44px;
  }

  .product-phone {
    width: 226px;
  }

  .map-note {
    min-width: auto;
    padding: 8px 10px;
    font-size: 12px;
  }

  .note-ui {
    top: 24px;
    left: 16px;
  }

  .note-api {
    top: 58px;
    right: 16px;
  }

  .note-db {
    right: 16px;
    bottom: 126px;
  }

  .note-admin {
    left: 16px;
    bottom: 120px;
  }

  .note-ops {
    bottom: 92px;
  }

  .map-core {
    display: grid;
    left: 12px;
    right: 12px;
    bottom: 10px;
    gap: 2px;
    padding: 12px;
  }

  .map-stop {
    grid-template-columns: 52px minmax(0, 1fr);
  }

  .map-stop > span {
    width: 44px;
    height: 44px;
    border-width: 4px;
  }

  .map-stop em {
    grid-column: 2;
  }

  .map-rail {
    display: none;
  }

  .chain-board article,
  .route-canvas article,
  .map-stop div,
  .compare-lanes article,
  .work-card {
    min-height: auto;
  }

  .featured-lane {
    transform: none;
  }

  .route-canvas,
  .learning-map,
  .compare-lanes,
  .workbench {
    gap: 12px;
  }

  .learning-map {
    padding: 22px;
  }

  .map-stop {
    grid-template-columns: 70px 1fr auto;
    align-items: center;
  }

  .map-stop div {
    padding: 16px;
  }

  .map-stop strong {
    font-size: 20px;
  }

  .map-deliverables {
    margin-top: 4px;
  }

  .stage-preview {
    min-height: 112px;
  }

  .before-after-table {
    grid-template-columns: 56px minmax(0, 1fr) minmax(0, 1fr);
    font-size: 13px;
  }

  .difference-table {
    grid-template-columns: 52px repeat(3, minmax(0, 1fr));
    font-size: 12px;
  }

  .before-after-table > *,
  .difference-table > * {
    padding: 12px 10px;
  }

  .hero-visual {
    padding: 10px;
  }

  .h5-showcase {
    padding: 8px;
  }

  .h5-phone-frame {
    width: min(252px, 100%);
    border-radius: 20px;
    padding: 6px;
  }

  .h5-phone-frame img {
    border-radius: 14px;
  }

  .shot-caption {
    display: grid;
    gap: 6px;
  }

  .shot-caption strong {
    text-align: left;
  }

  .problem-list div {
    grid-template-columns: 42px 1fr;
    gap: 10px;
  }

  .problem-list strong {
    font-size: 17px;
  }

  .process-line {
    grid-template-columns: 1fr;
  }

  .process-line span {
    min-height: 54px;
    justify-content: flex-start;
  }

  .value-list article {
    grid-template-columns: 1fr;
  }

  .value-list span {
    grid-row: auto;
  }

  .code-row {
    grid-template-columns: 1fr;
  }

  .board-flow {
    align-items: stretch;
    flex-direction: column;
  }

  .board-flow i {
    width: 1px;
    min-height: 10px;
    flex: 0 0 10px;
    margin-left: 16px;
  }

  .schema-row,
  .admin-panel {
    grid-template-columns: 1fr;
  }
}

@media print {
  body {
    display: none;
  }
}