/* ============================================================
   盐城车友会 yccyh.cn — 赛博朋克科技版
   暗色霓虹 · 青紫主色 · 玻璃拟态 · 网格/扫描背景
   断点：>1024 桌面 | 641–1024 平板 | ≤640 手机
   ============================================================ */

:root {
  --bg: #05070d;            /* 全局深底 */
  --bg-2: #0a0d18;
  --panel: rgba(17, 23, 42, .7);
  --panel-solid: #0e1426;
  --line: rgba(139, 92, 246, .18);
  --line-soft: rgba(255,255,255,.07);
  --ink: #eaf2ff;           /* 主文字(近白) */
  --body: #9aa7c7;          /* 正文(蓝灰) */
  --muted: #6b7a99;
  --cyan: #22d3ee;          /* 霓虹青 */
  --violet: #8b5cf6;        /* 霓虹紫 */
  --pink: #f472b6;
  --lime: #34d399;
  --amber: #f59e0b;
  --glow-cyan: 0 0 8px rgba(34,211,238,.55), 0 0 22px rgba(34,211,238,.28);
  --glow-violet: 0 0 8px rgba(139,92,246,.55), 0 0 26px rgba(139,92,246,.28);
  --radius: 16px;
  --shadow: 0 24px 60px -24px rgba(0,0,0,.7);
  --font: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI",
          "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "Orbitron", "Segoe UI", monospace, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 76px; }

body {
  font-family: var(--font);
  color: var(--body);
  line-height: 1.75;
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
body.menu-open { overflow: hidden; }

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

.container { width: min(1180px, 92%); margin: 0 auto; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---------------- 全局背景动效层 ---------------- */
.bg-fx { position: fixed; inset: 0; z-index: -1; pointer-events: none; overflow: hidden; }
.grid-layer {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(34,211,238,.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(34,211,238,.05) 1px, transparent 1px);
  background-size: 46px 46px;
  mask-image: radial-gradient(ellipse at 50% 0%, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 0%, #000 30%, transparent 75%);
}
.scan-line {
  position: absolute; left: 0; right: 0; height: 2px; top: 0;
  background: linear-gradient(90deg, transparent, rgba(139,92,246,.5), transparent);
  animation: scan 7s linear infinite;
}
@keyframes scan { 0% { top: 0; } 100% { top: 100%; } }
.aurora { position: absolute; border-radius: 50%; filter: blur(90px); opacity: .16; }
.aurora-a { width: 520px; height: 520px; background: var(--violet); top: -120px; left: -80px; animation: drift 14s ease-in-out infinite; }
.aurora-b { width: 420px; height: 420px; background: var(--cyan); bottom: -80px; right: -60px; animation: drift 18s ease-in-out infinite reverse; }
.aurora-c { width: 360px; height: 360px; background: var(--pink); top: 40%; left: 55%; opacity: .1; animation: drift 20s ease-in-out infinite; }
@keyframes drift { 0%,100% { transform: translate(0,0) scale(1); } 50% { transform: translate(40px,-30px) scale(1.1); } }

/* ---------------- 通用按钮 ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .4rem;
  padding: .95rem 2.1rem; border-radius: 12px;
  font-family: inherit; font-weight: 700; font-size: 1rem; letter-spacing: .3px;
  cursor: pointer; border: 1px solid transparent; position: relative;
  transition: transform .22s cubic-bezier(.2,.8,.3,1), box-shadow .22s, background .22s, color .22s;
  white-space: nowrap;
}
.btn:active { transform: scale(.97); }
.btn-primary {
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  color: #05070d; box-shadow: var(--glow-cyan);
  border-color: rgba(255,255,255,.18);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 0 14px rgba(34,211,238,.7), 0 0 34px rgba(139,92,246,.4); }
.btn-ghost {
  background: rgba(255,255,255,.04); color: var(--ink);
  border: 1px solid var(--line); backdrop-filter: blur(8px);
}
.btn-ghost:hover { background: rgba(34,211,238,.08); border-color: var(--cyan); box-shadow: var(--glow-cyan); transform: translateY(-2px); }
.btn-block { width: 100%; }

/* ---------------- 顶部导航 ---------------- */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(5,7,13,.7);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid var(--line-soft);
  transition: box-shadow .3s, background .3s;
}
.site-header.scrolled { background: rgba(10,13,24,.85); box-shadow: 0 10px 40px -12px rgba(0,0,0,.6); }
.nav-bar { display: flex; align-items: center; justify-content: space-between; height: 70px; }
.brand { display: flex; align-items: center; gap: .7rem; }
.brand-logo { width: 42px; height: 42px; flex: none; filter: drop-shadow(0 0 8px rgba(34,211,238,.5)); }
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-name { font-size: 1.28rem; font-weight: 900; color: var(--ink); letter-spacing: 1px; }
.brand-domain { font-size: .6rem; letter-spacing: 3px; font-weight: 700; font-family: var(--mono); color: var(--cyan); }

.nav-menu { display: flex; gap: .3rem; align-items: center; }
.nav-menu > li > a {
  color: var(--body); font-weight: 700; font-size: .97rem;
  padding: .5rem 1rem; border-radius: 10px; position: relative;
  transition: color .2s, background .2s, box-shadow .2s;
}
.nav-menu > li > a:hover { color: var(--cyan); background: rgba(34,211,238,.07); }
.nav-menu > li > a.active { color: var(--cyan); background: rgba(34,211,238,.08); box-shadow: inset 0 -2px 0 var(--cyan); }
.nav-menu > li > a.nav-cta {
  color: #05070d; background: linear-gradient(135deg,var(--cyan),var(--violet));
  box-shadow: var(--glow-cyan); margin-left: .6rem;
}
.nav-menu > li > a.nav-cta:hover { box-shadow: 0 0 14px rgba(34,211,238,.7), 0 0 30px rgba(139,92,246,.45); background: linear-gradient(135deg,var(--cyan),var(--violet)); }

.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: .4rem; }
.nav-toggle .bar { display: block; width: 26px; height: 3px; margin: 5px 0; background: var(--ink); border-radius: 3px; transition: transform .3s, opacity .3s; }

/* ---------------- Hero ---------------- */
.hero {
  position: relative; min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 130px 0 90px;
  color: #fff; text-align: center;
  overflow: hidden;
}
.hero::before {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 50% 0%, rgba(34,211,238,.14), transparent 60%),
    radial-gradient(ellipse 50% 40% at 70% 100%, rgba(139,92,246,.16), transparent 60%),
    radial-gradient(ellipse 40% 35% at 20% 90%, rgba(244,114,182,.1), transparent 60%);
}
.hero-content { position: relative; z-index: 2; max-width: 860px; }
.hero-eyebrow {
  display: inline-flex; align-items: center; gap: .6rem;
  font-size: .78rem; letter-spacing: 3px; font-weight: 700; font-family: var(--mono);
  color: var(--cyan); background: rgba(34,211,238,.08);
  border: 1px solid var(--line); padding: .5rem 1.3rem; border-radius: 30px;
  margin-bottom: 1.8rem;
}
.pulse-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--lime); box-shadow: 0 0 10px var(--lime); animation: pulse 1.6s ease-in-out infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: .35; } }

.hero h1 {
  font-size: clamp(2.3rem, 6vw, 4.4rem); font-weight: 900; line-height: 1.12;
  color: var(--ink); letter-spacing: 1px; font-family: var(--font);
}
.grad-text {
  background: linear-gradient(90deg, var(--cyan), var(--violet), var(--pink), var(--cyan));
  background-size: 300% 100%;
  -webkit-background-clip: text; background-clip: text; color: transparent;
  animation: gradSlide 6s linear infinite;
}
@keyframes gradSlide { 0% { background-position: 0% 50%; } 100% { background-position: 300% 50%; } }

.hero-lead { font-size: clamp(1.02rem, 2.5vw, 1.3rem); color: var(--body); margin: 1.4rem auto 2.4rem; max-width: 620px; font-weight: 500; }
.hero-actions { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }

.hero-stats {
  display: flex; justify-content: center; gap: 1.6rem; flex-wrap: wrap;
  margin-top: 3.6rem; padding: 1.7rem 1.6rem;
  background: var(--panel); border: 1px solid var(--line);
  border-radius: 18px; backdrop-filter: blur(12px);
  box-shadow: inset 0 1px 0 rgba(255,255,255,.06), var(--shadow);
}
.stat { display: flex; align-items: baseline; gap: .15rem; position: relative; padding: .2rem 1.8rem; }
.stat + .stat::before { content: ""; position: absolute; left: 0; top: 18%; height: 64%; width: 1px; background: var(--line); }
.stat-num { font-size: clamp(1.8rem,4vw,2.6rem); font-weight: 900; font-family: var(--mono); color: var(--cyan); text-shadow: var(--glow-cyan); }
.stat .suffix { font-size: 1.1rem; font-weight: 800; color: var(--violet); }
.stat-label { width: 100%; text-align: center; font-size: .82rem; color: var(--muted); order: 3; font-family: var(--mono); letter-spacing: 1px; }

.scroll-hint {
  position: absolute; left: 50%; bottom: 32px; transform: translateX(-50%);
  width: 26px; height: 44px; border: 2px solid rgba(34,211,238,.5); border-radius: 20px;
}
.scroll-hint span { position: absolute; top: 8px; left: 50%; width: 4px; height: 9px; margin-left: -2px; border-radius: 4px; background: var(--cyan); animation: scrollHint 1.8s ease-in-out infinite; }
@keyframes scrollHint { 0% { opacity: 1; transform: translateY(0); } 70% { opacity: 0; transform: translateY(14px); } 100% { opacity: 0; } }

/* ---------------- 通用 Section ---------------- */
.section { padding: 6rem 0; position: relative; }
.section-alt { background: var(--bg-2); border-top: 1px solid var(--line-soft); border-bottom: 1px solid var(--line-soft); }
.section-head { text-align: center; margin-bottom: 3rem; }
.section-tag {
  display: inline-block; font-size: .72rem; letter-spacing: 3px; font-weight: 700; font-family: var(--mono);
  color: var(--cyan); background: rgba(34,211,238,.07);
  border: 1px solid var(--line); padding: .38rem 1.1rem; border-radius: 30px; margin-bottom: 1.1rem;
}
.section-title { font-size: clamp(1.7rem, 4.2vw, 2.6rem); font-weight: 900; color: var(--ink); letter-spacing: .5px; }
.section-title::after {
  content: ""; display: block; width: 60px; height: 4px; margin: 1.1rem auto 0;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  border-radius: 3px; box-shadow: var(--glow-cyan);
}
.section-sub { color: var(--muted); margin-top: 1rem; font-size: 1.05rem; }

/* ---------------- 关于 ---------------- */
.about-grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: 2.8rem; align-items: stretch; }
.about-text p { margin-bottom: 1.1rem; color: var(--body); font-size: 1.05rem; }
.about-text strong { color: var(--cyan); font-weight: 900; }
.check-list { margin-top: 1.7rem; display: grid; gap: 1rem; }
.check-list li { display: flex; align-items: center; gap: .8rem; font-weight: 700; color: var(--ink); }
.tick {
  display: inline-flex; align-items: center; justify-content: center; flex: none;
  width: 26px; height: 26px; border-radius: 8px;
  background: linear-gradient(135deg,var(--cyan),var(--violet)); color: #05070d; font-size: .8rem; font-weight: 900;
  box-shadow: var(--glow-cyan);
}
.about-card {
  position: relative; display: flex; flex-direction: column; align-items: flex-start;
  background: var(--panel); border: 1px solid var(--line);
  border-radius: 20px; padding: 2.2rem; box-shadow: var(--shadow);
  overflow: hidden; transition: transform .3s cubic-bezier(.2,.8,.3,1), border .3s;
}
.about-card::before { content: ""; position: absolute; top: -80px; right: -80px; width: 200px; height: 200px; border-radius: 50%; background: radial-gradient(circle, rgba(139,92,246,.25), transparent 70%); }
.about-card:hover { transform: translateY(-6px); border-color: rgba(34,211,238,.4); }
.about-icon { width: 60px; height: 60px; margin-bottom: 1.2rem; filter: drop-shadow(0 0 12px rgba(34,211,238,.5)); }
.about-card h3 { font-size: 1.4rem; color: var(--ink); font-weight: 900; margin-bottom: .8rem; }
.about-card p { color: var(--body); margin-bottom: 1.5rem; }
.link-more { margin-top: auto; display: inline-flex; align-items: center; gap: .4rem; color: var(--cyan); font-weight: 800; }
.link-more span { transition: transform .25s; }
.link-more:hover span { transform: translateX(5px); }

/* ---------------- 活动 & 服务卡片 ---------------- */
.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.7rem; }
.card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: 18px; padding: 1.9rem;
  display: flex; flex-direction: column;
  backdrop-filter: blur(10px);
  transition: transform .3s cubic-bezier(.2,.8,.3,1), border .3s, box-shadow .3s;
  position: relative; overflow: hidden;
}
.card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  opacity: 0; transition: opacity .3s;
}
.card:hover { transform: translateY(-8px); border-color: rgba(34,211,238,.45); box-shadow: var(--shadow), var(--glow-cyan); }
.card:hover::before { opacity: 1; }
.card-top { display: flex; align-items: center; justify-content: space-between; margin-bottom: 1rem; }
.card-icon { color: var(--cyan); text-shadow: var(--glow-cyan); font-size: 1.6rem; }
.card-badge { font-size: .7rem; font-weight: 700; font-family: var(--mono); letter-spacing: 1.5px; color: var(--amber); background: rgba(245,158,11,.12); padding: .28rem .7rem; border-radius: 30px; border: 1px solid rgba(245,158,11,.3); }
.card-badge.badge-hot { color: var(--pink); background: rgba(244,114,182,.1); border-color: rgba(244,114,182,.3); }
.card-badge.badge-love { color: var(--lime); background: rgba(52,211,153,.1); border-color: rgba(52,211,153,.3); }
.card h3 { font-size: 1.22rem; color: var(--ink); font-weight: 900; margin-bottom: .45rem; }
.card-meta { display: flex; gap: 1rem; flex-wrap: wrap; color: var(--muted); font-size: .84rem; font-family: var(--mono); margin-bottom: .7rem; }
.card > p { color: var(--body); font-size: .96rem; }
.card-link { margin-top: auto; padding-top: 1rem; display: inline-flex; align-items: center; gap: .3rem; color: var(--cyan); font-weight: 800; cursor: pointer; }
.card-link span { transition: transform .25s; }
.card-link:hover span { transform: translateX(4px); }

.service-grid { grid-template-columns: repeat(4, 1fr); gap: 1.3rem; }
.service { text-align: center; align-items: center; padding: 2rem 1.3rem; }
.service-icon { width: 62px; height: 62px; margin-bottom: 1.1rem; filter: drop-shadow(0 0 10px rgba(34,211,238,.35)); }
.service h3 { color: var(--ink); font-size: 1.14rem; margin-bottom: .6rem; }
.service p { font-size: .88rem; color: var(--muted); }

/* ---------------- 旗下子站 ---------------- */
.ecosystem-note { text-align: center; color: var(--muted); margin: -1.6rem auto 2rem; max-width: 560px; font-size: .95rem; }
.subsite-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.6rem; }
.subsite {
  position: relative; display: flex; align-items: center; gap: 1.3rem;
  background: var(--panel); border: 1px solid var(--line); border-radius: 18px;
  padding: 1.9rem; overflow: hidden;
  backdrop-filter: blur(10px);
  transition: transform .3s cubic-bezier(.2,.8,.3,1), border .3s, box-shadow .3s;
}
.subsite-glow { position: absolute; top: -60px; right: -60px; width: 180px; height: 180px; border-radius: 50%; background: radial-gradient(circle, rgba(34,211,238,.28), transparent 70%); opacity: 0; transition: opacity .3s; }
.subsite:hover { transform: translateY(-6px); border-color: rgba(34,211,238,.5); box-shadow: var(--shadow), var(--glow-cyan); }
.subsite:hover .subsite-glow { opacity: 1; }
.subsite-icon {
  flex: none; width: 64px; height: 64px; border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.9rem; color: #05070d;
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  box-shadow: var(--glow-cyan);
}
.subsite-body { position: relative; z-index: 2; }
.subsite-body h3 { font-size: 1.25rem; color: var(--ink); font-weight: 900; margin-bottom: .2rem; }
.subsite-body p { font-size: .78rem; color: var(--muted); font-family: var(--mono); letter-spacing: 1px; margin-bottom: .5rem; }
.subsite-url { font-size: .86rem; font-weight: 700; font-family: var(--mono); color: var(--cyan); }
.subsite-url span { display: inline-block; transition: transform .25s; }
.subsite:hover .subsite-url span { transform: translate(2px,-2px); }

/* ---------------- 加入 ---------------- */
.join-section { background: linear-gradient(180deg, var(--bg-2), var(--bg)); }
.join-grid { display: grid; grid-template-columns: 1fr 1.25fr; gap: 2.8rem; align-items: start; }
.join-info h3 { font-size: 1.5rem; color: var(--ink); font-weight: 900; margin-bottom: .8rem; }
.join-info > p { margin-bottom: 1.6rem; }
.contact-list li { display: flex; align-items: center; gap: .7rem; margin: .85rem 0; color: var(--body); }
.contact-list svg { width: 22px; height: 22px; color: var(--cyan); flex: none; }
.contact-list a { color: var(--cyan); font-weight: 700; }
.contact-list a:hover { text-shadow: var(--glow-cyan); }

.join-form {
  background: var(--panel); border: 1px solid var(--line); border-radius: 20px;
  padding: 2.2rem; box-shadow: var(--shadow); backdrop-filter: blur(10px);
  display: grid; gap: .2rem;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.field { display: grid; gap: .35rem; margin-bottom: .7rem; }
.field label { font-weight: 700; font-size: .88rem; color: var(--ink); }
.join-form input, .join-form textarea {
  width: 100%; padding: .85rem 1.1rem;
  border: 1px solid var(--line-soft); border-radius: 11px;
  font-family: inherit; font-size: .98rem; color: var(--ink);
  background: rgba(5,7,13,.5); transition: border .2s, box-shadow .2s, background .2s;
}
.join-form input::placeholder, .join-form textarea::placeholder { color: var(--muted); }
.join-form input:focus, .join-form textarea:focus {
  outline: none; border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(34,211,238,.12), var(--glow-cyan);
  background: rgba(5,7,13,.7);
}
.form-tip { text-align: center; font-weight: 800; min-height: 1.3rem; margin-top: .3rem; color: var(--lime); }

/* ---------------- 页脚 ---------------- */
.site-footer { background: #03040a; border-top: 1px solid var(--line-soft); position: relative; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 3rem; padding: 3.8rem 0 2.6rem; }
.footer-grid h3 { color: var(--ink); margin-bottom: 1.1rem; font-size: 1.02rem; letter-spacing: .5px; }
.footer-grid p, .footer-grid ul li { color: var(--muted); }
.footer-grid nav ul li { margin: .55rem 0; }
.footer-grid nav a:hover, .footer-subs a:hover { color: var(--cyan); }
.footer-subs li { margin: .6rem 0; }
.footer-subs a { color: var(--body); font-weight: 600; }
.footer-bottom { border-top: 1px solid var(--line-soft); padding: 1.2rem 0; }
.footer-bottom p { font-size: .8rem; text-align: center; color: var(--muted); }

/* ---------------- 回到顶部 ---------------- */
.back-top {
  position: fixed; right: 1.5rem; bottom: 1.5rem; z-index: 90;
  width: 48px; height: 48px; border: 1px solid var(--line); border-radius: 12px;
  background: var(--panel); color: var(--cyan); font-size: 1.3rem; cursor: pointer;
  backdrop-filter: blur(10px);
  opacity: 0; visibility: hidden; transform: translateY(12px) scale(.9);
  transition: opacity .3s, transform .3s, visibility .3s, box-shadow .3s;
}
.back-top.show { opacity: 1; visibility: visible; transform: translateY(0) scale(1); }
.back-top:hover { color: #05070d; background: linear-gradient(135deg,var(--cyan),var(--violet)); box-shadow: var(--glow-cyan); }

/* ---------------- 滚动入场动画 ---------------- */
.reveal {
  opacity: 0; transform: translateY(34px);
  transition: opacity .7s cubic-bezier(.2,.8,.3,1), transform .7s cubic-bezier(.2,.8,.3,1);
  will-change: opacity, transform;
}
.reveal.revealed { opacity: 1; transform: translateY(0); }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1024px) {
  .service-grid { grid-template-columns: repeat(2, 1fr); }
  .subsite-grid { grid-template-columns: 1fr; }
  .hero-stats { gap: 1rem; padding: 1.4rem 1rem; }
  .stat { padding: .2rem 1rem; }
}

@media (max-width: 640px) {
  html { scroll-padding-top: 62px; }
  .section { padding: 4rem 0; }

  .nav-bar { height: 62px; }
  .brand-logo { width: 36px; height: 36px; }
  .brand-name { font-size: 1.1rem; }
  .nav-toggle { display: block; }
  .nav-menu {
    position: fixed; top: 62px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: rgba(10,13,24,.97); border-bottom: 1px solid var(--line);
    padding: 0 1.4rem; max-height: 0; overflow: hidden;
    transition: max-height .35s ease;
  }
  .nav-menu.open { max-height: 430px; padding: 1rem 1.4rem .6rem; }
  .nav-menu > li { border-bottom: 1px solid var(--line-soft); }
  .nav-menu > li:last-child { border-bottom: 0; }
  .nav-menu > li > a { display: block; padding: 1rem .4rem; border-radius: 8px; }
  .nav-menu > li > a.active { box-shadow: inset 2px 0 0 var(--cyan); }
  .nav-menu > li > a.nav-cta { margin-left: 0; margin-top: .6rem; text-align: center; }

  .nav-toggle.open .bar:nth-child(1) { transform: translateY(8px) rotate(45deg); }
  .nav-toggle.open .bar:nth-child(2) { opacity: 0; }
  .nav-toggle.open .bar:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

  .hero { min-height: 92vh; padding: 120px 0 80px; }
  .hero-stats { gap: .8rem; padding: 1.2rem .5rem; border-radius: 16px; }
  .stat { padding: .2rem .5rem; }
  .stat + .stat::before { display: none; }

  .about-grid, .join-grid, .card-grid { grid-template-columns: 1fr; }
  .service-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; gap: 0; }
  .subsite { flex-direction: column; align-items: flex-start; text-align: left; }
  .footer-grid { grid-template-columns: 1fr; gap: 2rem; padding: 2.8rem 0 1.6rem; }
  .back-top { right: 1rem; bottom: 1rem; width: 44px; height: 44px; }
}

@media (max-width: 420px) {
  .section-head { margin-bottom: 2.4rem; }
  .join-form { padding: 1.5rem; }
  .card { padding: 1.5rem; }
}

/* 减弱动画偏好：无障碍 */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
}