:root {
  color-scheme: light dark;
  --brand: #4f46e5;
  --brand-strong: #3730a3;
  --accent: #7c3aed;
  --success: #08745f;
  --danger: #b42318;
  --info: #0369a1;
  --ink: #17203b;
  --muted: #566078;
  --surface: #ffffff;
  --surface-soft: #f5f6ff;
  --line: #d8dbee;
  --warm: #fff8ea;
  --radius: 24px;
  --shadow: 0 20px 54px rgba(55, 48, 163, 0.12);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Noto Sans", "Noto Sans CJK SC", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background: var(--surface);
}

body {
  min-width: 320px;
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 82% 2%, rgba(165, 180, 252, 0.34), transparent 32rem),
    var(--surface);
  line-height: 1.55;
}

a {
  color: var(--brand-strong);
}

a:focus-visible,
button:focus-visible,
select:focus-visible {
  outline: 3px solid #0369a1;
  outline-offset: 3px;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

.skip-link {
  position: fixed;
  inset-block-start: 8px;
  inset-inline-start: 8px;
  z-index: 20;
  padding: 12px 16px;
  transform: translateY(-150%);
  border-radius: 12px;
  color: #fff;
  background: #17203b;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 72px;
  padding:
    max(10px, env(safe-area-inset-top))
    max(20px, env(safe-area-inset-right))
    10px
    max(20px, env(safe-area-inset-left));
  border-block-end: 1px solid color-mix(in srgb, var(--line) 82%, transparent);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  font-weight: 800;
  text-decoration: none;
}

.brand img {
  width: 46px;
  height: 46px;
  border-radius: 13px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.locale-select {
  min-height: 44px;
  max-width: 11rem;
  padding: 0 34px 0 12px;
  border: 1px solid var(--line);
  border-radius: 12px;
  color: var(--ink);
  background: var(--surface);
  font: inherit;
}

.shell {
  width: min(1120px, calc(100% - 40px));
  margin-inline: auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(280px, 0.9fr);
  align-items: center;
  gap: clamp(32px, 7vw, 88px);
  min-height: min(780px, calc(100svh - 72px));
  padding-block: clamp(64px, 10vw, 120px);
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--brand-strong);
  font-size: 0.88rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.12;
  text-wrap: balance;
}

h1 {
  max-width: 13ch;
  margin: 0;
  font-size: clamp(2.6rem, 7vw, 5.8rem);
  letter-spacing: -0.055em;
}

h2 {
  margin: 0 0 18px;
  font-size: clamp(2rem, 4vw, 3.2rem);
  letter-spacing: -0.035em;
}

h3 {
  margin: 0 0 8px;
  font-size: 1.2rem;
}

.lead {
  max-width: 58ch;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: clamp(1.05rem, 2vw, 1.28rem);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-block-start: 30px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 20px;
  border: 2px solid transparent;
  border-radius: 14px;
  font-weight: 800;
  text-decoration: none;
  transition: transform 120ms ease, box-shadow 220ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-primary {
  color: #fff;
  background: var(--brand-strong);
  box-shadow: 0 10px 28px rgba(55, 48, 163, 0.28);
}

.button-secondary {
  border-color: var(--brand-strong);
  color: var(--brand-strong);
  background: var(--surface);
}

.hero-card {
  position: relative;
  overflow: hidden;
  padding: clamp(20px, 4vw, 38px);
  border: 1px solid rgba(165, 180, 252, 0.55);
  border-radius: 36px;
  background: linear-gradient(145deg, #072d2a, #126b5d);
  box-shadow: var(--shadow);
}

.hero-card::after {
  position: absolute;
  inset: auto -20% -46% 20%;
  width: 22rem;
  height: 22rem;
  border-radius: 50%;
  background: rgba(189, 234, 221, 0.13);
  content: "";
}

.hero-card img {
  position: relative;
  z-index: 1;
  width: min(100%, 480px);
  margin-inline: auto;
  border-radius: 26px;
}

.section {
  padding-block: clamp(64px, 9vw, 112px);
}

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

.section-head {
  max-width: 700px;
  margin-block-end: 32px;
}

.section-head p {
  color: var(--muted);
}

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

.card {
  min-width: 0;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: 0 8px 26px rgba(23, 32, 59, 0.05);
}

.card p {
  margin-block-end: 0;
  color: var(--muted);
}

.pill {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  margin-block-end: 16px;
  padding: 5px 11px;
  border-radius: 999px;
  color: #085e4e;
  background: #dff8ee;
  font-size: 0.82rem;
  font-weight: 800;
}

.story-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.story {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--surface);
}

.story img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.story figcaption {
  padding: 20px;
}

.study-line {
  display: grid;
  gap: 3px;
}

.hanzi {
  font-family: "Noto Sans CJK SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 1.4rem;
  font-weight: 750;
}

.pinyin {
  color: var(--brand-strong);
  font-weight: 700;
}

.notice,
.legal-card {
  padding: 24px;
  border-inline-start: 5px solid var(--brand);
  border-radius: 16px;
  background: var(--surface-soft);
}

.legal {
  width: min(820px, calc(100% - 40px));
  margin-inline: auto;
  padding-block: 56px 96px;
}

.legal h1 {
  max-width: none;
  font-size: clamp(2.2rem, 5vw, 4rem);
}

.legal h2 {
  margin-block-start: 48px;
  font-size: 1.6rem;
}

.legal p,
.legal li {
  color: var(--muted);
}

.legal li + li {
  margin-block-start: 8px;
}

.review-meta {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-block: 28px;
}

.site-footer {
  padding:
    40px
    max(20px, env(safe-area-inset-right))
    max(40px, env(safe-area-inset-bottom))
    max(20px, env(safe-area-inset-left));
  border-block-start: 1px solid var(--line);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 18px;
  width: min(1120px, 100%);
  margin-inline: auto;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.footer-links a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
}

[dir="rtl"] .locale-select {
  padding: 0 12px 0 34px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #f5f4ff;
    --muted: #c8c9d8;
    --surface: #111426;
    --surface-soft: #181c33;
    --line: #353a59;
    --brand-strong: #a5b4fc;
    --shadow: 0 20px 54px rgba(0, 0, 0, 0.32);
  }

  .button-primary {
    color: #14162b;
    background: #a5b4fc;
  }

  .button-secondary {
    color: #c7d2fe;
    border-color: #a5b4fc;
  }

  .pill {
    color: #b8f6e4;
    background: #123e36;
  }
}

@media (max-width: 760px) {
  .hero,
  .grid,
  .story-grid,
  .review-meta {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
  }

  .brand span {
    display: none;
  }
}

@media (max-width: 460px) {
  .shell {
    width: min(100% - 28px, 1120px);
  }

  .site-header {
    padding-inline: 14px;
  }

  .header-actions .button {
    display: none;
  }

  .locale-select {
    max-width: 9.5rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}