:root {
  --teal: #0f6b5c;
  --teal-soft: rgba(15, 107, 92, 0.12);
  --ink: #1c1917;
  --muted: #57534e;
  --line: #e7e5e4;
  --bg: #f3faf7;
  --card: #ffffff;
  --shell-glow: rgba(15, 107, 92, 0.08);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body.site-a {
  color: var(--ink);
  background:
    radial-gradient(920px 380px at 10% -4%, rgba(15, 107, 92, 0.14), transparent 55%),
    radial-gradient(700px 320px at 96% 8%, rgba(45, 136, 112, 0.1), transparent 50%),
    linear-gradient(180deg, #e8f6f1 0%, var(--bg) 42%, #f7fbf9 100%);
  font-family: "Trebuchet MS", "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.7;
  min-height: 100vh;
  position: relative;
  -webkit-font-smoothing: antialiased;
}
/* 加花：网格 + 角饰 */
body.site-a::before {
  content: "";
  pointer-events: none;
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(15, 107, 92, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(15, 107, 92, 0.035) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(ellipse at 50% 28%, #000 18%, transparent 72%);
  opacity: 0.7;
  z-index: 0;
}
body.site-a::after {
  content: "";
  pointer-events: none;
  position: fixed;
  width: 180px;
  height: 180px;
  right: 4vw;
  top: 18vh;
  background:
    radial-gradient(circle at 30% 30%, rgba(15, 107, 92, 0.18), transparent 55%),
    radial-gradient(circle at 70% 65%, rgba(45, 136, 112, 0.14), transparent 50%);
  border-radius: 50%;
  filter: blur(2px);
  z-index: 0;
}
/* 同框描边壳 */
.shell-frame {
  pointer-events: none;
  position: fixed;
  inset: 12px;
  border: 1px solid rgba(15, 107, 92, 0.18);
  border-radius: 24px;
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.7),
    0 22px 60px var(--shell-glow);
  z-index: 1;
}
.shell-flower {
  pointer-events: none;
  position: fixed;
  z-index: 1;
  width: 72px;
  height: 72px;
  opacity: 0.55;
  background:
    radial-gradient(circle at 50% 50%, rgba(15, 107, 92, 0.22) 0 6px, transparent 7px),
    conic-gradient(from 20deg, rgba(15, 107, 92, 0.12), transparent 40%, rgba(15, 107, 92, 0.12), transparent 75%, rgba(15, 107, 92, 0.1));
  border-radius: 50%;
}
.shell-flower.tl { top: 28px; left: 28px; }
.shell-flower.br { bottom: 28px; right: 28px; }
@media (max-width: 720px) {
  .shell-frame { inset: 6px; border-radius: 14px; }
  .shell-flower { width: 48px; height: 48px; opacity: 0.4; }
  .shell-flower.tl { top: 14px; left: 14px; }
  .shell-flower.br { bottom: 14px; right: 14px; }
}
.top, .banner, main, footer, .site-header, .shell-banner {
  position: relative;
  z-index: 2;
}
.top {
  display: flex; justify-content: space-between; align-items: center;
  padding: 22px 7vw 0; gap: 16px; flex-wrap: wrap;
}
.brand {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: clamp(20px, 3vw, 28px); font-weight: 800; letter-spacing: -0.03em;
  color: var(--teal); text-decoration: none;
}
.brand img { display: block; border-radius: 7px; }
.brand small {
  display: block; font-size: 11px; font-weight: 600; color: var(--muted);
  letter-spacing: 0.02em; margin-top: 1px;
}
.brand-mark { display: flex; flex-direction: column; line-height: 1.15; }
.top nav { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }
.top a { color: var(--muted); text-decoration: none; font-size: 14px; font-weight: 600; }
.top a:hover { color: var(--teal); }
.lang button {
  border: 1px solid var(--line); background: #fff; color: var(--muted);
  border-radius: 999px; padding: 4px 10px; cursor: pointer; font-size: 12px;
}
.lang button.on { background: var(--teal); color: #fff; border-color: var(--teal); }
.banner, .shell-banner {
  margin: 18px 7vw 0; padding: 10px 14px; border-radius: 10px;
  background: rgba(15, 107, 92, 0.08); color: var(--muted); font-size: 13px;
  border: 1px solid rgba(15, 107, 92, 0.08);
}
main { padding: 4vh 7vw 56px; max-width: 880px; }
.hero { padding: 4vh 0 2vh; }
.eyebrow { color: var(--teal); font-weight: 700; font-size: 13px; letter-spacing: 0.04em; }
.hero h1 {
  font-size: clamp(26px, 4.6vw, 42px); line-height: 1.2; margin: 8px 0 14px; letter-spacing: -0.03em;
}
.lead { font-size: 17px; color: var(--muted); max-width: 38em; }
.guide-note {
  margin: 8px 0 0; padding: 14px 16px; border-radius: 12px;
  background: rgba(255,255,255,0.72); border: 1px solid var(--line);
  color: var(--muted); font-size: 14px;
}
section { padding: 26px 0; border-top: 1px solid var(--line); }
h2 { font-size: 20px; margin-bottom: 10px; }
p, li { font-size: 16px; color: #292524; margin: 8px 0; }
ul { padding-left: 1.2em; }
.cards { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); border-top: 0; padding-top: 8px; }
.card {
  display: block; text-decoration: none; color: inherit; background: var(--card);
  border: 1px solid var(--line); border-radius: 14px; padding: 16px 16px 18px;
  box-shadow: 0 10px 28px rgba(28, 25, 23, 0.04);
  transition: border-color 0.2s ease, transform 0.2s ease;
}
.card:hover { border-color: rgba(15, 107, 92, 0.35); transform: translateY(-2px); }
.card strong { display: block; margin-bottom: 6px; color: var(--teal); }
.card span { color: var(--muted); font-size: 14px; }
footer { padding: 0 7vw 40px; color: var(--muted); font-size: 13px; }
footer a { color: var(--teal); }
body.lang-en .zh { display: none !important; }
body.lang-zh .en { display: none !important; }
body:not(.lang-en):not(.lang-zh) .en { display: none !important; }
@media (max-width: 720px) {
  .top nav a:nth-child(n+4):nth-child(-n+5) { display: none; }
}