:root {
  color-scheme: light dark;
  --background: #f4f7fb;
  --surface: rgba(255, 255, 255, 0.82);
  --text: #142033;
  --muted: #58667a;
  --line: rgba(20, 32, 51, 0.12);
  --accent: #1769e0;
  --accent-soft: rgba(23, 105, 224, 0.1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --background: #0b1019;
    --surface: rgba(20, 28, 42, 0.84);
    --text: #f1f5fb;
    --muted: #a9b5c6;
    --line: rgba(255, 255, 255, 0.12);
    --accent: #6ca6ff;
    --accent-soft: rgba(108, 166, 255, 0.13);
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    radial-gradient(circle at 20% 0%, var(--accent-soft), transparent 34rem),
    var(--background);
  color: var(--text);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", sans-serif;
}

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

a:hover {
  text-decoration-thickness: 2px;
}

.shell {
  width: min(760px, calc(100% - 40px));
  margin: 0 auto;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 28px 0;
}

.brand {
  color: var(--text);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
}

nav {
  display: flex;
  gap: 18px;
  font-size: 0.9rem;
}

main {
  padding: 56px 0 72px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

h1,
h2 {
  letter-spacing: -0.035em;
}

h1 {
  max-width: 680px;
  margin: 0;
  font-size: clamp(2.35rem, 8vw, 4.8rem);
  line-height: 1.02;
}

h2 {
  margin: 0 0 12px;
  font-size: 1.35rem;
  line-height: 1.25;
}

p {
  margin: 0 0 14px;
}

.lede {
  max-width: 650px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: 1.12rem;
}

.grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 48px;
}

.card,
.policy-section {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
  box-shadow: 0 16px 44px rgba(15, 32, 56, 0.07);
  backdrop-filter: blur(18px);
}

.card {
  padding: 24px;
}

.card p,
.policy-section p,
.policy-section li {
  color: var(--muted);
}

.contact {
  grid-column: 1 / -1;
}

.button {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  margin-top: 4px;
  padding: 9px 15px;
  border-radius: 10px;
  background: var(--accent);
  color: white;
  font-weight: 650;
  text-decoration: none;
}

.policy {
  display: grid;
  gap: 16px;
  margin-top: 44px;
}

.policy-section {
  padding: 26px;
}

.policy-section ul {
  margin: 8px 0 0;
  padding-left: 22px;
}

.zh {
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 24px 0 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.84rem;
}

@media (max-width: 620px) {
  .shell {
    width: min(100% - 28px, 760px);
  }

  header,
  footer {
    align-items: flex-start;
    flex-direction: column;
  }

  main {
    padding-top: 36px;
  }

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

  .contact {
    grid-column: auto;
  }
}