:root {
  color-scheme: dark;
  --bg: #080b12;
  --surface: #101621;
  --surface-soft: #0d121c;
  --text: #eef3ff;
  --muted: #a7b1c3;
  --line: rgba(255, 255, 255, 0.11);
  --accent: #7b8cff;
  --accent-2: #43d7bd;
  --max: 920px;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  min-width: 280px;
  color: var(--text);
  background:
    radial-gradient(circle at 10% -10%, rgba(123, 140, 255, 0.2), transparent 34rem),
    radial-gradient(circle at 95% 0%, rgba(67, 215, 189, 0.1), transparent 28rem),
    var(--bg);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 17px;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
}

a { color: #aeb9ff; text-underline-offset: 0.2em; }
a:hover { color: #d7dcff; }
a:focus-visible { outline: 3px solid var(--accent-2); outline-offset: 4px; border-radius: 3px; }

.skip-link {
  position: fixed;
  z-index: 10;
  left: 1rem;
  top: 1rem;
  transform: translateY(-200%);
  padding: 0.6rem 0.9rem;
  color: #07100f;
  background: var(--accent-2);
  border-radius: 0.5rem;
  font-weight: 700;
}
.skip-link:focus { transform: none; }

.shell { width: min(calc(100% - 2.5rem), var(--max)); margin-inline: auto; }

.hero {
  position: relative;
  overflow: hidden;
  padding: 4rem 0 3.5rem;
  border-bottom: 1px solid var(--line);
}

.hero::after {
  content: "";
  position: absolute;
  width: 19rem;
  height: 19rem;
  right: max(-6rem, calc((100vw - var(--max)) / 2 - 10rem));
  top: 1rem;
  border: 1px solid rgba(123, 140, 255, 0.2);
  border-radius: 50%;
  box-shadow: 0 0 0 3rem rgba(123, 140, 255, 0.025), 0 0 0 7rem rgba(67, 215, 189, 0.018);
  pointer-events: none;
}

.brand { display: inline-flex; align-items: center; gap: 0.7rem; font-weight: 750; letter-spacing: 0.02em; }
.mark { display: grid; place-items: center; width: 2rem; height: 2rem; border-radius: 0.55rem; color: #091018; background: linear-gradient(135deg, var(--accent), var(--accent-2)); font-weight: 900; }
.eyebrow { margin: 3.25rem 0 0.65rem; color: var(--accent-2); font-size: 0.78rem; font-weight: 800; letter-spacing: 0.18em; }
h1 { max-width: 780px; margin: 0; font-size: clamp(2.45rem, 7vw, 5rem); line-height: 1.04; letter-spacing: -0.045em; }
h1 span { display: block; color: transparent; background: linear-gradient(90deg, #b8c2ff, #83ebd9); background-clip: text; -webkit-background-clip: text; }
.summary { max-width: 680px; margin: 1.5rem 0 0; color: #c7cfdd; font-size: 1.08rem; }
.summary.zh { margin-top: 0.35rem; color: var(--muted); }
.meta { display: flex; flex-wrap: wrap; gap: 0.35rem 1rem; margin-top: 2rem; color: var(--muted); font-size: 0.92rem; }
.meta span { color: #dde3ef; font-weight: 700; }
.language-nav { display: flex; gap: 0.6rem; margin-top: 1.6rem; }
.language-nav a { display: inline-flex; min-width: 6rem; justify-content: center; padding: 0.45rem 0.9rem; border: 1px solid var(--line); border-radius: 99rem; color: var(--text); text-decoration: none; background: rgba(255, 255, 255, 0.035); }
.language-nav a:hover { border-color: rgba(123, 140, 255, 0.65); background: rgba(123, 140, 255, 0.12); }

.policy { padding-block: 3rem 5rem; }
.notice { display: grid; gap: 0.3rem; margin-bottom: 4rem; padding: 1.25rem 1.4rem; border: 1px solid rgba(67, 215, 189, 0.24); border-radius: 1rem; background: rgba(67, 215, 189, 0.055); }
.notice strong { color: #8cede0; }
.notice span { color: #c0cad9; }

article { scroll-margin-top: 1.5rem; }
.section-heading { display: flex; align-items: center; gap: 1rem; margin-bottom: 2.5rem; }
.section-number { flex: 0 0 auto; display: grid; place-items: center; width: 3.25rem; height: 3.25rem; border-radius: 50%; border: 1px solid rgba(123, 140, 255, 0.45); color: #c8d0ff; font-weight: 800; font-size: 0.8rem; }
h2 { margin: 0; font-size: clamp(2rem, 5vw, 3rem); line-height: 1.15; letter-spacing: -0.03em; }
section { padding: 1.45rem 0; border-top: 1px solid var(--line); }
h3 { margin: 0 0 0.65rem; font-size: 1.18rem; line-height: 1.4; letter-spacing: -0.01em; }
p { margin: 0.65rem 0; color: var(--muted); }
strong { color: #e3e8f4; }
ul { margin: 0.8rem 0 0; padding-left: 1.35rem; color: var(--muted); }
li + li { margin-top: 0.65rem; }
li::marker { color: var(--accent-2); }
.divider { height: 1px; margin: 5rem 0; background: linear-gradient(90deg, transparent, rgba(123, 140, 255, 0.55), rgba(67, 215, 189, 0.45), transparent); }

footer { border-top: 1px solid var(--line); color: #7f8a9d; background: rgba(0, 0, 0, 0.12); font-size: 0.84rem; }
footer .shell { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 0.5rem 1.5rem; padding-block: 1.5rem; }

@media (max-width: 640px) {
  body { font-size: 16px; }
  .shell { width: min(calc(100% - 1.5rem), var(--max)); }
  .hero { padding: 2.5rem 0 2.75rem; }
  .eyebrow { margin-top: 2.5rem; }
  .policy { padding-top: 2rem; }
  .notice { margin-bottom: 3rem; }
  .section-heading { align-items: flex-start; }
  .section-number { width: 2.8rem; height: 2.8rem; }
  .divider { margin: 3.5rem 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

@media print {
  :root { color-scheme: light; --bg: #fff; --text: #111827; --muted: #374151; --line: #d1d5db; }
  body { background: #fff; color: var(--text); font-size: 11pt; }
  .hero { padding: 1cm 0; }
  .hero::after, .language-nav, .skip-link { display: none; }
  h1 span { color: var(--text); background: none; }
  .policy { padding-block: 1cm; }
  section { break-inside: avoid; }
  a { color: inherit; }
}