:root {
  --bg: #f3f5f8;
  --ink: #111827;
  --muted: #5f6b7a;
  --line: rgba(17, 24, 39, 0.08);
  --card: rgba(255, 255, 255, 0.78);
  --card-strong: rgba(255, 255, 255, 0.9);
  --accent: #1d4ed8;
  --accent-ink: #0f172a;
  --accent-soft: #dbe7ff;
  --shadow: 0 24px 60px rgba(17, 24, 39, 0.08);
  --radius-xl: 36px;
  --radius-lg: 28px;
  --radius-md: 22px;
  --radius-sm: 16px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  color: var(--ink);
  font-family: "SF Pro Display", "Avenir Next", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background:
    radial-gradient(circle at top left, rgba(123, 176, 255, 0.28), transparent 28%),
    radial-gradient(circle at top right, rgba(255, 210, 150, 0.24), transparent 24%),
    linear-gradient(180deg, #f7f9fc 0%, #eef2f7 48%, #f6f8fb 100%);
}

body[data-lang="zh"] .copy-en,
body[data-lang="en"] .copy-zh {
  display: none !important;
}

body[data-lang="dual"] .copy-zh,
body[data-lang="dual"] .copy-en {
  display: block;
}

body[data-lang="zh"] .copy-zh,
body[data-lang="en"] .copy-en {
  display: block;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    radial-gradient(circle at 20% 20%, rgba(255, 255, 255, 0.78), transparent 32%),
    radial-gradient(circle at 80% 10%, rgba(59, 130, 246, 0.08), transparent 18%);
  pointer-events: none;
}

a {
  color: var(--accent);
}

nav {
  position: sticky;
  top: 16px;
  z-index: 20;
  width: min(1320px, calc(100vw - 32px));
  margin: 20px auto 0;
  padding: 10px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.74);
  border: 1px solid rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(18px);
  box-shadow: var(--shadow);
}

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.05);
}

.lang-pill {
  border: none;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.82rem;
  cursor: pointer;
  transition: background 180ms ease, color 180ms ease, transform 180ms ease;
}

.lang-pill.active {
  background: linear-gradient(135deg, var(--accent-ink), var(--accent));
  color: #fff;
}

.lang-pill:hover {
  transform: translateY(-1px);
}

nav a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 16px;
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: transform 180ms ease, background 180ms ease, color 180ms ease;
}

nav a:hover,
nav a.active {
  transform: translateY(-1px);
  background: linear-gradient(135deg, var(--accent-ink), var(--accent));
  color: #fff;
}

.c,
.container {
  position: relative;
  z-index: 1;
  width: min(1320px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 36px 0 56px;
}

body.thinker-page .container,
body.lesson-page .container {
  width: min(980px, calc(100vw - 32px));
}

.hero,
.header,
.course-header {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-xl);
  padding: 34px;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.94), rgba(255, 255, 255, 0.64)),
    linear-gradient(125deg, #ffffff 0%, #e8eef8 55%, #d6e3ff 100%);
  border: 1px solid rgba(255, 255, 255, 0.72);
  box-shadow: var(--shadow);
  text-align: center;
}

.hero::after,
.header::after,
.course-header::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 85% 15%, rgba(15, 23, 42, 0.09), transparent 22%),
    radial-gradient(circle at 75% 78%, rgba(96, 165, 250, 0.14), transparent 18%);
  pointer-events: none;
}

.hero > *,
.header > *,
.course-header > * {
  position: relative;
  z-index: 1;
}

.hero {
  padding-top: 46px;
  padding-bottom: 42px;
}

.hero h1,
.header h1,
.course-header h1 {
  color: var(--accent-ink);
  letter-spacing: -0.04em;
}

.hero h1 {
  font-size: clamp(2.6rem, 6vw, 4.4rem);
}

.header h1,
.course-header h1 {
  font-size: clamp(1.9rem, 5vw, 3rem);
  margin-bottom: 8px;
}

.hero p,
.subtitle,
.signature,
.ci-sub,
.section p,
.audio-player .audio-label,
.course-nav a,
.course-nav span {
  color: #465467;
}

.hero p {
  margin-top: 12px;
  font-size: 1.02rem;
  line-height: 1.8;
}

.hero .stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 24px;
}

.hero .stat {
  padding: 18px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.68);
  border: 1px solid rgba(17, 24, 39, 0.08);
}

.hero .sn {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
  color: var(--accent);
}

.hero .sl {
  margin-top: 6px;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

h2 {
  margin: 28px 0 14px;
  padding: 0 4px;
  color: var(--accent-ink);
  font-size: 1rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.thinker-grid,
.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 14px;
}

.tc,
.ci-card,
.section,
.audio-player,
.course-nav {
  border-radius: var(--radius-md);
  background: var(--card);
  backdrop-filter: blur(18px);
  border: 1px solid rgba(255, 255, 255, 0.72);
  box-shadow: var(--shadow);
}

.tc,
.ci-card {
  position: relative;
  overflow: hidden;
  text-decoration: none;
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease, background 180ms ease;
}

.tc {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px;
  color: var(--ink);
}

.tc::before {
  content: "智";
  width: 52px;
  height: 52px;
  border-radius: 18px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  background: linear-gradient(135deg, var(--accent-ink), var(--accent));
  color: #fff;
  font-weight: 700;
  font-size: 1rem;
  box-shadow: 0 18px 38px rgba(17, 24, 39, 0.12);
}

.tc:hover,
.ci-card:hover,
.course-index a:hover,
.course-nav a:hover {
  transform: translateY(-2px);
}

.tc:hover,
.ci-card:hover {
  border-color: rgba(29, 78, 216, 0.18);
  background: rgba(255, 255, 255, 0.92);
}

.tc b,
.ci-title {
  display: block;
  color: var(--accent-ink);
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.35;
}

.tc small,
.ci-sub,
.subtitle {
  font-size: 0.88rem;
  line-height: 1.6;
}

.tt,
.tag,
.badge {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 10px;
  border-radius: 999px;
  background: rgba(29, 78, 216, 0.08);
  color: var(--accent);
  font-size: 0.74rem;
  font-weight: 600;
}

.header .tags {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

.signature {
  margin: 18px auto 0;
  max-width: 560px;
  padding: 16px 18px;
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent);
  background: rgba(255, 255, 255, 0.66);
  text-align: left;
  font-style: italic;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 16px;
  margin-bottom: 18px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(255, 255, 255, 0.72);
  box-shadow: var(--shadow);
  color: var(--accent-ink);
  text-decoration: none;
  font-size: 0.92rem;
  transition: transform 180ms ease, background 180ms ease;
}

.back-link:hover {
  transform: translateY(-1px);
  background: rgba(255, 255, 255, 0.92);
  text-decoration: none;
}

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

.ci-card {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  align-items: center;
  gap: 16px;
  padding: 18px 20px;
  color: var(--ink);
}

.ci-num {
  width: 64px;
  height: 64px;
  border-radius: 22px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, var(--accent-ink), var(--accent));
  color: #fff;
  font-size: 0.9rem;
  font-weight: 700;
  box-shadow: 0 18px 36px rgba(17, 24, 39, 0.12);
}

.section {
  padding: 24px 24px 22px;
  margin-bottom: 18px;
}

.section h2 {
  margin: 0 0 12px;
  padding: 0;
  color: var(--accent);
  letter-spacing: 0.08em;
  text-transform: none;
  font-size: 1rem;
}

.section p {
  font-size: 0.96rem;
  line-height: 1.85;
  white-space: pre-line;
}

.audio-player {
  display: grid;
  gap: 10px;
  padding: 18px;
  margin-bottom: 24px;
}

.audio-player .audio-label {
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.audio-player audio {
  width: 100%;
  height: 42px;
}

.course-nav {
  display: grid;
  gap: 14px;
  padding: 18px;
  margin-top: 28px;
}

.course-nav > a,
.course-nav > span {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  width: fit-content;
  padding: 0 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid rgba(17, 24, 39, 0.08);
  text-decoration: none;
}

.course-nav > a {
  color: var(--accent-ink);
}

.course-nav .disabled {
  opacity: 0.55;
  color: var(--muted);
}

.course-index {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(116px, 1fr));
  gap: 10px;
}

.course-index a {
  display: grid;
  place-items: center;
  min-height: 46px;
  padding: 0 10px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(17, 24, 39, 0.08);
  color: #425063;
  text-decoration: none;
  font-size: 0.84rem;
  transition: transform 180ms ease, border-color 180ms ease, color 180ms ease, background 180ms ease;
}

.course-index a.current {
  background: linear-gradient(135deg, var(--accent-ink), var(--accent));
  border-color: transparent;
  color: #fff;
}

.course-index a.completed {
  opacity: 0.55;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 10px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.06);
  color: var(--muted);
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.spark-system,
.reference-shelf,
.learning-grid,
.lesson-kpis,
.spark-grid,
.capsule-grid {
  margin-bottom: 22px;
}

.spark-system {
  padding: 24px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.88), rgba(255, 255, 255, 0.68));
  border: 1px solid rgba(255, 255, 255, 0.72);
  box-shadow: var(--shadow);
}

.reference-shelf {
  padding: 24px;
  border-radius: var(--radius-lg);
  background:
    linear-gradient(135deg, rgba(15, 23, 42, 0.96), rgba(30, 41, 59, 0.88)),
    linear-gradient(135deg, rgba(123, 176, 255, 0.12), rgba(255, 255, 255, 0.02));
  border: 1px solid rgba(96, 165, 250, 0.16);
  box-shadow: 0 26px 64px rgba(15, 23, 42, 0.18);
}

.reference-shelf .section-head {
  margin-bottom: 16px;
}

.reference-shelf .section-head h3,
.reference-shelf .section-head p,
.reference-shelf .section-head .copy-en,
.reference-shelf h4 {
  color: #e5edf8;
}

.reference-shelf .eyebrow {
  background: rgba(255, 255, 255, 0.1);
  color: rgba(229, 237, 248, 0.92);
}

.reference-group + .reference-group {
  margin-top: 18px;
}

.reference-group h4 {
  margin: 0 0 12px;
  font-size: 0.96rem;
  letter-spacing: 0.04em;
}

.reference-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 14px;
}

.reference-card {
  display: grid;
  gap: 8px;
  padding: 18px;
  min-height: 100%;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: 0 18px 42px rgba(15, 23, 42, 0.14);
  backdrop-filter: blur(12px);
}

.reference-kind {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  min-height: 24px;
  padding: 0 10px;
  border-radius: 999px;
  background: rgba(147, 197, 253, 0.14);
  color: #bfdbfe;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.reference-card strong {
  color: #f8fbff;
  line-height: 1.4;
}

.reference-meta {
  color: rgba(203, 213, 225, 0.88);
  font-size: 0.8rem;
  line-height: 1.55;
}

.reference-card p {
  color: rgba(226, 232, 240, 0.92);
  line-height: 1.72;
  font-size: 0.92rem;
}

.reference-card .copy-en {
  color: rgba(191, 219, 254, 0.86);
}

.section-head {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(280px, 0.9fr);
  gap: 18px;
  align-items: start;
  margin-bottom: 18px;
}

.section-head h3 {
  margin-top: 10px;
  color: var(--accent-ink);
  font-size: clamp(1.4rem, 3vw, 2.2rem);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.section-head p {
  color: #465467;
  font-size: 0.96rem;
  line-height: 1.8;
}

.blueprint-grid,
.domain-grid,
.learning-grid,
.lesson-kpis,
.spark-grid,
.capsule-grid {
  display: grid;
  gap: 14px;
}

.blueprint-grid {
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  margin-bottom: 14px;
}

.domain-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.blueprint-card,
.domain-card,
.learning-card,
.kpi-card,
.spark-card,
.capsule,
.module-card {
  border-radius: var(--radius-md);
  border: 1px solid rgba(17, 24, 39, 0.08);
  background: rgba(255, 255, 255, 0.78);
  box-shadow: 0 18px 42px rgba(17, 24, 39, 0.06);
}

.blueprint-card,
.domain-card,
.learning-card,
.kpi-card,
.spark-card,
.capsule {
  padding: 18px;
}

.blueprint-card strong,
.domain-card strong,
.learning-card strong,
.kpi-card strong,
.spark-card strong,
.capsule strong,
.module-card strong {
  display: block;
  color: var(--accent-ink);
  line-height: 1.35;
}

.blueprint-card p,
.domain-card p,
.learning-card p,
.kpi-card p,
.spark-card p,
.capsule p,
.module-card p {
  margin-top: 8px;
  color: #465467;
  line-height: 1.7;
  font-size: 0.92rem;
}

.copy-en {
  color: #5f6b7a;
}

.copy-en:not(strong):not(b):not(h1):not(h2):not(h3) {
  font-size: 0.92rem;
}

.blueprint-card small,
.domain-card small,
.module-card small,
.mini-note {
  display: block;
  margin-top: 10px;
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.55;
}

.domain-card {
  border-top: 4px solid var(--domain-accent, var(--accent));
}

.domain-top {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
}

.domain-top span,
.course-note {
  color: var(--muted);
  font-size: 0.8rem;
}

.learning-grid,
.lesson-kpis,
.spark-grid,
.capsule-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.learning-card,
.kpi-card,
.spark-card,
.capsule {
  min-height: 100%;
}

.kpi-card span {
  display: block;
  margin-bottom: 10px;
  color: var(--muted);
  font-size: 0.76rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.thinker-system {
  margin-top: 22px;
}

.module-ladder {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
}

.source-grid,
.case-grid,
.detail-dual-grid {
  display: grid;
  gap: 14px;
  margin-bottom: 22px;
}

.source-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.case-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.detail-dual-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.module-card {
  padding: 18px;
  position: relative;
  overflow: hidden;
}

.module-card::after {
  content: "";
  position: absolute;
  inset: auto -20% -55% 35%;
  height: 120px;
  background: radial-gradient(circle, rgba(29, 78, 216, 0.12), transparent 70%);
  pointer-events: none;
}

.module-card > * {
  position: relative;
  z-index: 1;
}

.source-card,
.case-card {
  padding: 18px;
  border-radius: var(--radius-md);
  border: 1px solid rgba(17, 24, 39, 0.08);
  background: rgba(255, 255, 255, 0.78);
  box-shadow: 0 18px 42px rgba(17, 24, 39, 0.06);
}

.source-card strong,
.case-card strong {
  display: block;
  color: var(--accent-ink);
  line-height: 1.35;
}

.source-card p,
.case-card p {
  margin-top: 8px;
  color: #465467;
  line-height: 1.7;
  font-size: 0.92rem;
}

.source-card small,
.case-card small {
  display: block;
  margin-top: 10px;
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.6;
}

.header-tags,
.header .tags {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

.bullet-list,
.action-list {
  padding-left: 1.25rem;
  display: grid;
  gap: 10px;
}

.bullet-list li,
.action-list li {
  color: #334155;
  line-height: 1.8;
}

.subtle-list li {
  color: #516071;
}

.memory-line {
  background:
    linear-gradient(135deg, rgba(219, 231, 255, 0.72), rgba(255, 255, 255, 0.82)),
    rgba(255, 255, 255, 0.74);
}

.memory-line p {
  font-size: 1rem;
  color: var(--accent-ink);
}

.mini-note {
  margin-top: 8px;
}

@media (max-width: 960px) {
  nav {
    top: 10px;
    width: calc(100vw - 24px);
  }

  .c,
  .container {
    width: calc(100vw - 24px);
  }

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

  .section-head {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 680px) {
  .hero,
  .header,
  .course-header {
    padding: 24px 20px;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .header h1,
  .course-header h1 {
    font-size: 1.5rem;
  }

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

  .ci-card {
    grid-template-columns: 1fr;
  }

  .ci-num {
    width: 56px;
    height: 56px;
  }

  .course-nav {
    padding: 16px;
  }
}