:root {
  color-scheme: light;
  --ink: #122033;
  --muted: #59697a;
  --paper: #fffdf8;
  --soft: #eef7f6;
  --panel: #ffffff;
  --line: #dce6ee;
  --blue: #2563eb;
  --teal: #0f9f8f;
  --shadow: 0 16px 44px rgba(18, 32, 51, 0.08);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: #f7fafb;
  color: var(--ink);
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 72px;
  padding: 0 44px;
  border-bottom: 1px solid rgba(220, 230, 238, 0.9);
  background: rgba(255, 253, 248, 0.92);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 18px;
  font-weight: 800;
  white-space: nowrap;
}

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 8px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--muted);
  font-size: 15px;
  font-weight: 700;
}

.nav a {
  border-radius: 8px;
  padding: 10px 12px;
}

.nav a:hover {
  background: #e8f1ff;
  color: var(--blue);
}

.hero {
  min-height: 620px;
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(90deg, rgba(238, 247, 246, 0.95), rgba(247, 250, 251, 0.84)),
    radial-gradient(circle at 88% 14%, rgba(37, 99, 235, 0.16), transparent 34%),
    radial-gradient(circle at 78% 78%, rgba(15, 159, 143, 0.14), transparent 36%),
    var(--soft);
}

.hero-inner {
  width: min(1040px, calc(100% - 64px));
  margin: 0 auto;
  padding: 104px 0 92px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--blue);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 820px;
  margin-bottom: 24px;
  font-size: clamp(50px, 7vw, 92px);
  line-height: 1.04;
  letter-spacing: 0;
}

h1 span {
  display: block;
}

.hero-subtitle {
  max-width: 790px;
  color: #31475a;
  font-size: clamp(21px, 2.4vw, 31px);
  font-weight: 650;
  line-height: 1.55;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 36px;
}

.primary-link,
.secondary-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 52px;
  border-radius: 8px;
  padding: 0 22px;
  font-weight: 800;
}

.primary-link {
  background: var(--blue);
  color: #fff;
}

.secondary-link {
  border: 1px solid rgba(18, 32, 51, 0.18);
  background: rgba(255, 255, 255, 0.78);
  color: var(--ink);
}

.section {
  padding: 86px 0;
}

.section:nth-of-type(2n) {
  background: var(--paper);
}

.section-inner {
  width: min(1040px, calc(100% - 64px));
  margin: 0 auto;
}

h2 {
  max-width: 780px;
  margin-bottom: 28px;
  font-size: clamp(34px, 4vw, 56px);
  line-height: 1.16;
  letter-spacing: 0;
}

.feature-grid,
.link-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.feature-card,
.link-grid a,
.legal-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.feature-card,
.link-grid a {
  padding: 24px;
}

.feature-card {
  border-top: 5px solid var(--teal);
}

.feature-card:nth-child(2) {
  border-top-color: var(--blue);
}

.feature-card h3,
.link-grid strong {
  display: block;
  margin-bottom: 12px;
  font-size: 22px;
}

.feature-card p,
.link-grid span {
  display: block;
  margin: 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.7;
}

.legal-page {
  background: #eef4f8;
}

.legal-hero {
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.legal-hero .section-inner {
  padding: 72px 0 46px;
}

.legal-hero h1 {
  max-width: 900px;
  margin-bottom: 12px;
  font-size: clamp(42px, 5vw, 72px);
}

.updated {
  color: #77899a;
  font-size: 15px;
}

.legal-card {
  padding: clamp(26px, 5vw, 48px);
}

.legal-card h2 {
  margin: 38px 0 12px;
  font-size: clamp(25px, 2.4vw, 34px);
}

.legal-card h2:first-child {
  margin-top: 0;
}

.legal-card p,
.legal-card li {
  color: #405367;
  font-size: 17px;
  line-height: 1.85;
}

.legal-card ul {
  margin: 0 0 22px;
  padding-left: 22px;
}

.legal-card a {
  color: var(--blue);
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 34px 44px;
  background: var(--ink);
  color: #fff;
}

.site-footer a {
  color: rgba(255, 255, 255, 0.78);
}

@media (max-width: 920px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
    padding: 14px 20px;
  }

  .nav {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 2px;
  }

  .nav a {
    white-space: nowrap;
  }

  .feature-grid,
  .link-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .hero {
    min-height: auto;
  }

  .hero-inner,
  .section-inner {
    width: calc(100% - 36px);
  }

  .hero-inner {
    padding: 54px 0 64px;
  }

  .section {
    padding: 62px 0;
  }

  h1 {
    font-size: 48px;
  }

  h2 {
    font-size: 34px;
  }

  .hero-subtitle {
    font-size: 19px;
  }

  .feature-grid,
  .link-grid {
    grid-template-columns: 1fr;
  }

  .site-footer {
    align-items: flex-start;
    flex-direction: column;
    padding: 28px 20px;
  }
}