:root {
  --bg: #f5f5f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --line: #e5e5ea;
  --accent: #1f5fd6;
  --hero: #0f2a5c;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --card: #1c1c1e;
    --text: #f5f5f7;
    --muted: #a1a1a6;
    --line: #38383a;
    --accent: #5e9bff;
    --hero: #0b1f45;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.top {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--line);
}
.top .wrap { display: flex; align-items: center; gap: 12px; height: 52px; }
.top .brand { display: flex; align-items: center; gap: 8px; font-weight: 600; color: var(--text); }
.top .brand img { width: 26px; height: 26px; border-radius: 6px; }
.top nav { margin-left: auto; display: flex; gap: 18px; font-size: 14px; }
.top nav a { color: var(--muted); }
.top nav a.on { color: var(--text); }
.lang { font-size: 13px; padding: 3px 10px; border: 1px solid var(--line); border-radius: 999px; color: var(--muted); }

.wrap { max-width: 880px; margin: 0 auto; padding: 0 20px; }

.hero {
  background: linear-gradient(160deg, var(--hero), #1f4fa8);
  color: #fff; text-align: center; padding: 56px 20px 48px;
}
.hero img { width: 112px; height: 112px; border-radius: 26px; box-shadow: 0 10px 30px rgba(0,0,0,.35); }
.hero h1 { font-size: 34px; margin: 18px 0 6px; letter-spacing: .5px; }
.hero p { margin: 0 auto; max-width: 560px; color: rgba(255,255,255,.85); }
.hero .badges { margin-top: 18px; display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; }
.hero .badges span { font-size: 13px; padding: 3px 10px; border-radius: 999px; background: rgba(255,255,255,.14); }

main { padding: 28px 0 56px; }
.card { background: var(--card); border-radius: 16px; padding: 22px 24px; margin: 0 0 16px; border: 1px solid var(--line); }
.card h2 { font-size: 20px; margin: 0 0 12px; }
.card h3 { font-size: 16px; margin: 18px 0 6px; }
.card p, .card li { color: var(--text); }
.card ul { padding-left: 1.2em; margin: 6px 0; }
.muted { color: var(--muted); font-size: 14px; }

.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 12px; }
.feat { border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; }
.feat b { display: block; margin-bottom: 4px; }

details { border-top: 1px solid var(--line); padding: 12px 0; }
details:first-of-type { border-top: 0; }
summary { cursor: pointer; font-weight: 600; list-style: none; }
summary::-webkit-details-marker { display: none; }
summary::before { content: "＋"; color: var(--accent); margin-right: 8px; }
details[open] summary::before { content: "－"; }
details p, details ul { margin: 8px 0 0 1.6em; }

.contact { text-align: center; }
.contact .mail { display: inline-block; margin-top: 6px; font-size: 18px; font-weight: 600; }

table { width: 100%; border-collapse: collapse; font-size: 15px; }
th, td { text-align: left; padding: 8px 6px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: var(--muted); font-weight: 500; }

footer { border-top: 1px solid var(--line); padding: 20px 0 40px; color: var(--muted); font-size: 13px; text-align: center; }
footer a { color: var(--muted); }

[lang="en"] .zh-only, [lang="zh-CN"] .en-only { display: none; }