/* ============================================================
   666浏览器 · 产品官网 全局样式
   设计方向：深空科技感 —— 深蓝黑底 + 青绿霓虹光 + 网格纹理
   响应式：PC(≥1024) / PAD(768-1023) / 手机(<768)
   ============================================================ */

:root {
  --bg: #04060e;
  --bg-2: #070d1d;
  --panel: rgba(15, 23, 46, 0.55);
  --panel-solid: #0a1122;
  --line: rgba(140, 170, 255, 0.14);
  --line-strong: rgba(140, 170, 255, 0.28);
  --txt: #eaf0ff;
  --muted: #8b9cc0;
  --cyan: #35f0e0;
  --blue: #4c8dff;
  --gold: #ffb454;
  --font-d: "Chakra Petch", "Noto Sans SC", "PingFang SC", sans-serif;
  --font-b: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;
  --radius: 14px;
  --nav-h: 64px;
  --maxw: 1180px;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--txt);
  font-family: var(--font-b);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* ---------- 背景层：网格 + 光晕 ---------- */
.bg-grid {
  position: fixed;
  inset: 0;
  z-index: -2;
  background-image:
    linear-gradient(rgba(140, 170, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(140, 170, 255, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 40%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 40%, transparent 100%);
  pointer-events: none;
}

.bg-glow {
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(600px 420px at 18% -5%, rgba(76, 141, 255, 0.16), transparent 62%),
    radial-gradient(560px 400px at 85% 8%, rgba(53, 240, 224, 0.10), transparent 62%),
    radial-gradient(700px 520px at 50% 110%, rgba(53, 240, 224, 0.07), transparent 60%);
}

/* ---------- 排版 ---------- */
h1, h2, h3 { font-family: var(--font-d); font-weight: 600; line-height: 1.2; }

.section { position: relative; padding: 96px 24px; }
.section-inner { max-width: var(--maxw); margin: 0 auto; }

.sec-head { text-align: center; margin-bottom: 56px; }
.sec-head .kicker {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--font-d);
  font-size: 13px; letter-spacing: 0.28em; color: var(--cyan);
  text-transform: uppercase;
}
.sec-head .kicker::before,
.sec-head .kicker::after {
  content: ""; width: 26px; height: 1px; background: linear-gradient(90deg, transparent, var(--cyan));
}
.sec-head .kicker::after { transform: rotate(180deg); }
.sec-head h2 { font-size: clamp(28px, 4.2vw, 42px); margin-top: 14px; }
.sec-head .sub { color: var(--muted); max-width: 620px; margin: 14px auto 0; font-size: 15px; }

.grad-text {
  background: linear-gradient(100deg, var(--cyan) 10%, var(--blue) 55%, var(--cyan) 90%);
  background-size: 200% auto;
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  animation: grad-move 2.5s ease 1;
}
@keyframes grad-move { to { background-position: 200% center; } }

/* ---------- 导航 ---------- */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: var(--nav-h);
  display: flex; align-items: center;
  transition: background 0.3s, border-color 0.3s, backdrop-filter 0.3s;
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: rgba(4, 6, 14, 0.78);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
}
.nav-inner {
  width: 100%; max-width: var(--maxw);
  margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; gap: 24px;
}
.logo {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--font-d); font-weight: 700; font-size: 20px;
  color: var(--txt); text-decoration: none; letter-spacing: 0.02em;
}
.logo .mark {
  width: 32px; height: 32px; border-radius: 9px;
  display: grid; place-items: center;
  background: linear-gradient(135deg, rgba(53,240,224,.16), rgba(76,141,255,.16));
  border: 1px solid var(--line-strong);
  color: var(--cyan);
  font-size: 15px;
  box-shadow: 0 0 18px rgba(53, 240, 224, 0.25);
}
.nav-links { display: flex; gap: 6px; margin-left: 8px; }
.nav-links a {
  padding: 8px 14px; border-radius: 8px;
  color: var(--muted); text-decoration: none; font-size: 15px;
  transition: color 0.2s, background 0.2s;
}
.nav-links a:hover { color: var(--txt); background: rgba(140,170,255,0.08); }
.nav-links a.active { color: var(--cyan); }
.nav-cta { margin-left: auto; }

.nav-burger {
  display: none; margin-left: auto;
  width: 40px; height: 40px; border-radius: 9px;
  background: rgba(140,170,255,0.08); border: 1px solid var(--line);
  color: var(--txt); font-size: 18px; cursor: pointer;
  align-items: center; justify-content: center;
}

/* 移动端抽屉菜单 */
.mobile-menu {
  position: fixed; top: var(--nav-h); left: 0; right: 0; z-index: 99;
  background: rgba(6, 10, 22, 0.97);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line);
  padding: 12px 24px 20px;
  display: none;
  flex-direction: column; gap: 4px;
  transform: translateY(-8px); opacity: 0;
  transition: transform 0.25s, opacity 0.25s;
  pointer-events: none;
}
.mobile-menu.open { display: flex; transform: translateY(0); opacity: 1; pointer-events: auto; }
.mobile-menu a {
  padding: 12px 14px; border-radius: 10px;
  color: var(--muted); text-decoration: none; font-size: 16px;
}
.mobile-menu a:hover { color: var(--txt); background: rgba(140,170,255,0.08); }
.mobile-menu a.active { color: var(--cyan); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--font-d);
  font-weight: 600; font-size: 15px; letter-spacing: 0.05em;
  padding: 13px 26px; border-radius: 12px;
  text-decoration: none; cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s, border-color 0.2s;
  border: 1px solid transparent;
  white-space: nowrap;
}
.btn-primary {
  color: #04130f;
  background: linear-gradient(135deg, var(--cyan), #7df5b0);
  box-shadow: 0 8px 30px rgba(53, 240, 224, 0.35);
  position: relative; overflow: hidden;
}
.btn-primary::after {
  content: ""; position: absolute; top: 0; left: -80%;
  width: 60%; height: 100%;
  background: linear-gradient(100deg, transparent, rgba(255,255,255,0.55), transparent);
  transform: skewX(-20deg);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 40px rgba(53, 240, 224, 0.5); }

.btn-ghost {
  color: var(--txt);
  background: rgba(140, 170, 255, 0.06);
  border-color: var(--line-strong);
}
.btn-ghost:hover { transform: translateY(-2px); border-color: var(--cyan); box-shadow: 0 8px 24px rgba(53, 240, 224, 0.18); }

.btn-lg { padding: 16px 34px; font-size: 16px; }
.btn-sm { padding: 9px 16px; font-size: 13px; border-radius: 9px; }
.btn-block { width: 100%; justify-content: center; }

/* ---------- HERO ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  padding: calc(var(--nav-h) + 40px) 24px 72px;
  text-align: center;
  overflow: hidden;
}
.hero .badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 16px; border-radius: 999px;
  border: 1px solid var(--line-strong);
  background: rgba(140, 170, 255, 0.06);
  color: var(--muted); font-size: 13px;
  font-family: var(--font-d);
  letter-spacing: 0.06em;
  margin-bottom: 26px;
  animation: fade-down 0.7s ease both 0.1s;
}
.hero .badge .dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 10px var(--cyan);
}
@keyframes fade-down { from { opacity: 0; transform: translateY(-14px); } }

.hero h1 {
  font-size: clamp(40px, 7.2vw, 78px);
  font-weight: 700; letter-spacing: 0.01em;
  animation: fade-up 0.8s ease both 0.2s;
}
.hero h1 .line { display: block; }
.hero .lead {
  max-width: 640px; margin: 22px auto 0;
  color: var(--muted); font-size: clamp(15px, 2vw, 18px);
  animation: fade-up 0.8s ease both 0.35s;
}
.hero .lead ul {
  margin: 14px 0 0; padding: 0;
  list-style: none;
  display: grid; gap: 8px;
}
.hero .lead li {
  display: flex; align-items: center; justify-content: flex-start; gap: 10px;
  color: var(--muted);
}
.hero .lead li::before {
  content: ""; width: 14px; height: 14px;
  background: var(--cyan);
  -webkit-mask: url('data:image/svg+xml;charset=utf-8,%3Csvg xmlns=%27http://www.w3.org/2000/svg%27 viewBox=%270 0 24 24%27%3E%3Cpath d=%27M9 16.17L4.83 12l-1.42 1.41L9 19 21 7l-1.41-1.41z%27/%3E%3C/svg%3E') no-repeat center / contain;
  mask: url('data:image/svg+xml;charset=utf-8,%3Csvg xmlns=%27http://www.w3.org/2000/svg%27 viewBox=%270 0 24 24%27%3E%3Cpath d=%27M9 16.17L4.83 12l-1.42 1.41L9 19 21 7l-1.41-1.41z%27/%3E%3C/svg%3E') no-repeat center / contain;
  flex-shrink: 0;
}
@keyframes fade-up { from { opacity: 0; transform: translateY(18px); } }

.hero-actions {
  display: flex; gap: 16px; justify-content: center; flex-wrap: wrap;
  margin-top: 34px;
  animation: fade-up 0.8s ease both 0.5s;
}
.hero-meta {
  margin-top: 30px;
  display: flex; gap: 26px; justify-content: center; flex-wrap: wrap;
  color: var(--muted); font-size: 13px;
  font-family: var(--font-d); letter-spacing: 0.08em;
  animation: fade-up 0.8s ease both 0.65s;
}
.hero-meta span { display: inline-flex; align-items: center; gap: 7px; }
.hero-meta .ic { color: var(--cyan); }

/* 浏览器窗口演示 */
.browser-mock {
  position: relative;
  width: min(880px, 92vw);
  margin: 76px auto 0;
  animation: fade-up 1s ease both 0.8s;
}

.browser-window {
  border-radius: 16px;
  border: 1px solid var(--line-strong);
  background: linear-gradient(180deg, rgba(13, 20, 42, 0.92), rgba(7, 11, 24, 0.96));
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.55),
    0 0 0 1px rgba(53, 240, 224, 0.05),
    0 0 60px rgba(53, 240, 224, 0.12);
  overflow: hidden;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}
.browser-bar {
  display: flex; align-items: center; gap: 12px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  background: rgba(140, 170, 255, 0.04);
}
.traffic { display: flex; gap: 7px; }
.traffic i { width: 11px; height: 11px; border-radius: 50%; }
.traffic i:nth-child(1) { background: #ff5f57; }
.traffic i:nth-child(2) { background: #febc2e; }
.traffic i:nth-child(3) { background: #28c840; }

.mock-tabs { display: flex; gap: 8px; flex: 1; min-width: 0; }
.mock-tab {
  flex: 1; max-width: 150px; height: 26px; border-radius: 7px 7px 0 0;
  background: rgba(140, 170, 255, 0.1);
  border: 1px solid var(--line);
  border-bottom: none;
  display: flex; align-items: center; gap: 6px; padding: 0 10px;
  font-size: 10px; color: var(--muted);
}
.mock-tab.active {
  background: rgba(53, 240, 224, 0.08);
  border-color: var(--line-strong);
  color: var(--cyan);
}
.mock-tab i { width: 9px; height: 9px; border-radius: 2px; background: var(--cyan); opacity: 0.7; }
.mock-tab .x { margin-left: auto; opacity: 0.4; }

.mock-addr {
  display: flex; align-items: center; gap: 8px;
  flex: 1; min-width: 0;
  background: rgba(4, 6, 14, 0.7);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 7px 12px;
  font-family: var(--font-d); font-size: 11px; color: var(--muted);
  letter-spacing: 0.04em;
}
.mock-addr .lock { color: var(--cyan); }
.mock-addr .url { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; flex: 1; text-align: left; }
.mock-addr .refresh { color: var(--cyan); display: inline-block; }

.browser-body { position: relative; padding: 0; }
.mock-site {
  padding: 26px 30px 34px;
  text-align: left;
  position: relative;
}
.mock-site::before {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(340px 200px at 18% 8%, rgba(76, 141, 255, 0.16), transparent 70%),
    radial-gradient(300px 180px at 85% 20%, rgba(53, 240, 224, 0.12), transparent 70%);
  pointer-events: none;
}
.mock-site .m-title {
  font-family: var(--font-d); font-size: 20px; font-weight: 700;
  display: flex; align-items: center; gap: 12px;
}
.mock-site .m-title .typing {
  color: var(--cyan); display: inline-block;
  border-right: 2px solid var(--cyan);
  padding-right: 4px;
}

.mock-site .m-lead { color: var(--muted); font-size: 12px; margin-top: 10px; max-width: 60%; }
.mock-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 20px; }
.mock-card {
  height: 52px; border-radius: 10px;
  background: rgba(140, 170, 255, 0.06);
  border: 1px solid var(--line);
  display: flex; flex-direction: column; justify-content: center; gap: 7px;
  padding: 0 12px;
}
.mock-card i {
  height: 5px; border-radius: 3px;
  background: linear-gradient(90deg, var(--cyan), var(--blue));
  animation: bar-load 1.2s ease-out 1;
}
.mock-card i:nth-child(2) { width: 55%; animation-delay: 0.15s; }
.mock-card i:nth-child(3) { width: 78%; animation-delay: 0.3s; }
@keyframes bar-load { from { width: 12%; opacity: 0.5; } }

/* ---------- 特性卡片 ---------- */
.features { background: var(--bg-2); }
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.feat-card {
  position: relative;
  padding: 28px 26px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--panel);
  overflow: hidden;
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}
.feat-card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  opacity: 0; transition: opacity 0.3s;
}
.feat-card:hover {
  transform: translateY(-6px);
  border-color: var(--line-strong);
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.45), 0 0 30px rgba(53, 240, 224, 0.1);
}
.feat-card:hover::before { opacity: 1; }
.feat-card .icon {
  width: 46px; height: 46px; border-radius: 12px;
  display: grid; place-items: center;
  background: linear-gradient(135deg, rgba(53,240,224,.14), rgba(76,141,255,.14));
  border: 1px solid var(--line-strong);
  color: var(--cyan); font-size: 20px;
  margin-bottom: 18px;
  transition: transform 0.3s;
}
.feat-card:hover .icon { transform: scale(1.08) rotate(-4deg); }
.feat-card h3 { font-size: 18px; margin-bottom: 10px; }
.feat-card p { color: var(--muted); font-size: 14px; }
.feat-card .tag {
  display: inline-block; margin-top: 14px;
  font-family: var(--font-d); font-size: 11px; letter-spacing: 0.14em;
  color: var(--blue); text-transform: uppercase;
}

/* ---------- 数据徽章区 ---------- */
.stats { position: relative; }
.stats-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}
.stat {
  text-align: center; padding: 30px 16px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--panel);
}
.stat .num {
  font-family: var(--font-d); font-weight: 700;
  font-size: clamp(30px, 4vw, 44px);
  background: linear-gradient(135deg, var(--cyan), var(--blue));
  -webkit-background-clip: text; background-clip: text; color: transparent;
  display: inline-block;
}
.stat .num .suffix { font-size: 0.6em; }
.stat .label { color: var(--muted); font-size: 13px; margin-top: 8px; letter-spacing: 0.1em; }

/* ---------- 安全双栏 ---------- */
.security { background: var(--bg-2); }
.sec-split {
  display: grid; grid-template-columns: 1.05fr 1fr; gap: 56px; align-items: center;
}
.sec-split h2 { font-size: clamp(26px, 3.6vw, 38px); margin: 14px 0 18px; }
.sec-split p { color: var(--muted); font-size: 15px; }
.point-list { margin-top: 24px; display: grid; gap: 14px; }
.point {
  display: flex; gap: 14px; align-items: flex-start;
  padding: 16px 18px; border-radius: 12px;
  border: 1px solid var(--line);
  background: var(--panel);
}
.point .ic {
  width: 34px; height: 34px; flex: none;
  border-radius: 9px; display: grid; place-items: center;
  background: rgba(53, 240, 224, 0.1);
  color: var(--cyan); font-size: 15px;
}
.point b { display: block; font-family: var(--font-d); font-weight: 600; font-size: 15px; }
.point small { color: var(--muted); font-size: 13px; }

/* 本地优先视觉展示 */
.vault-visual {
  position: relative;
  height: 520px;
  border-radius: 18px;
  border: 1px solid var(--line-strong);
  background:
    radial-gradient(420px 260px at 50% 30%, rgba(53, 240, 224, 0.12), transparent 70%),
    var(--panel);
  overflow: hidden;
  display: grid; place-items: center;
}
.vault-ring {
  position: relative; width: 64%; aspect-ratio: 1;
  border-radius: 50%;
  border: 1px dashed rgba(53, 240, 224, 0.4);
  display: grid; place-items: center;
}
.vault-ring::before {
  content: ""; position: absolute; top: -6px; left: 50%;
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--cyan); box-shadow: 0 0 16px var(--cyan);
}
.vault-core {
  position: absolute; width: 44%; aspect-ratio: 1; border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, rgba(53, 240, 224, 0.35), rgba(76, 141, 255, 0.16) 60%, transparent);
  border: 1px solid rgba(53, 240, 224, 0.35);
  display: grid; place-items: center;
  font-family: var(--font-d); font-weight: 700; font-size: 22px; color: var(--cyan);
  box-shadow: 0 0 44px rgba(53, 240, 224, 0.22);
}
.vault-note {
  position: absolute; bottom: 14px; left: 0; right: 0;
  text-align: center; font-family: var(--font-d); font-size: 12px;
  color: var(--muted); letter-spacing: 0.14em;
}

/* ---------- CTA banner ---------- */
.cta-banner {
  position: relative;
  max-width: var(--maxw); margin: 0 auto;
  padding: 56px 40px;
  border-radius: 22px;
  text-align: center;
  overflow: hidden;
  border: 1px solid var(--line-strong);
  background:
    radial-gradient(520px 300px at 20% 0%, rgba(76, 141, 255, 0.18), transparent 70%),
    radial-gradient(480px 280px at 85% 100%, rgba(53, 240, 224, 0.14), transparent 70%),
    var(--panel-solid);
}
.cta-banner h2 { font-size: clamp(26px, 4vw, 38px); }
.cta-banner p { color: var(--muted); margin: 14px auto 0; max-width: 520px; }
.cta-banner .btn { margin-top: 28px; }

/* ---------- FAQ ---------- */
.faq-list { max-width: 780px; margin: 0 auto; display: grid; gap: 14px; }
.faq-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--panel);
  overflow: hidden;
  transition: border-color 0.25s;
}
.faq-item.open { border-color: var(--line-strong); }
.faq-q {
  width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 18px 22px;
  background: none; border: none; cursor: pointer;
  color: var(--txt); font-size: 15px; text-align: left;
  font-family: var(--font-b); font-weight: 500;
}
.faq-q .arrow {
  flex: none; color: var(--cyan); font-family: var(--font-d);
  transition: transform 0.25s;
}
.faq-item.open .arrow { transform: rotate(45deg); }
.faq-a {
  max-height: 0; overflow: hidden;
  transition: max-height 0.3s ease;
}
.faq-a-inner { padding: 0 22px 18px; color: var(--muted); font-size: 14px; }

/* ---------- 页脚 ---------- */
footer { border-top: 1px solid var(--line); background: rgba(4, 6, 14, 0.6); }
.footer-inner {
  max-width: var(--maxw); margin: 0 auto;
  padding: 44px 24px 28px;
  display: grid; grid-template-columns: 1.4fr repeat(3, 1fr); gap: 36px;
}
.footer-col .logo { margin-bottom: 14px; }
.footer-col p { color: var(--muted); font-size: 13px; max-width: 280px; }
.footer-col h4 {
  font-family: var(--font-d); font-size: 13px; letter-spacing: 0.18em;
  color: var(--txt); text-transform: uppercase; margin-bottom: 14px;
}
.footer-col a {
  display: block; padding: 5px 0;
  color: var(--muted); text-decoration: none; font-size: 14px;
  transition: color 0.2s;
}
.footer-col a:hover { color: var(--cyan); }
.footer-bottom {
  border-top: 1px solid var(--line);
  padding: 18px 24px;
  max-width: var(--maxw); margin: 0 auto;
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  color: var(--muted); font-size: 12.5px;
}
.footer-bottom a { color: var(--muted); text-decoration: none; }
.footer-bottom a:hover { color: var(--cyan); }

/* ---------- 内页 hero（下载 / 历史版本） ---------- */
.page-hero {
  padding: calc(var(--nav-h) + 64px) 24px 48px;
  text-align: center;
  position: relative;
}
.page-hero h1 { font-size: clamp(34px, 5.4vw, 56px); }
.page-hero .lead { color: var(--muted); max-width: 600px; margin: 16px auto 0; font-size: 16px; }
.page-hero .badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px; border-radius: 999px;
  border: 1px solid var(--line-strong);
  background: rgba(140, 170, 255, 0.06);
  color: var(--muted); font-size: 12.5px;
  font-family: var(--font-d); letter-spacing: 0.06em;
  margin-bottom: 22px;
}

/* ---------- 下载页 ---------- */
.platforms-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px; }
.platform-card {
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--panel);
  padding: 30px 26px;
  text-align: center;
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}
.platform-card:hover {
  transform: translateY(-6px);
  border-color: var(--line-strong);
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.45), 0 0 26px rgba(53, 240, 224, 0.1);
}
.platform-card .p-icon {
  width: 58px; height: 58px; margin: 0 auto 16px;
  border-radius: 15px;
  display: grid; place-items: center;
  background: linear-gradient(135deg, rgba(53,240,224,.14), rgba(76,141,255,.14));
  border: 1px solid var(--line-strong);
  font-size: 26px;
}
.platform-card h3 { font-size: 20px; }
.platform-card .p-ver { font-family: var(--font-d); font-size: 12px; color: var(--muted); margin: 4px 0 18px; letter-spacing: 0.1em; }
.platform-card .btn { margin-top: 14px; }
.platform-card .dl-meta {
  margin-top: 14px; font-size: 12px; color: var(--muted);
  font-family: var(--font-d);
}
.arch-row { display: flex; gap: 10px; margin-top: 16px; }
.arch-row .btn { flex: 1; }

.spec-table {
  width: 100%; border-collapse: collapse;
  border-radius: 12px; overflow: hidden;
  background: var(--panel);
}
.spec-table th, .spec-table td {
  padding: 14px 18px; text-align: left; font-size: 14px;
  border-bottom: 1px solid var(--line);
}
.spec-table th {
  font-family: var(--font-d); font-weight: 600; color: var(--cyan);
  background: rgba(140, 170, 255, 0.05); width: 180px;
  letter-spacing: 0.06em;
}
.spec-table tr:last-child th, .spec-table tr:last-child td { border-bottom: none; }
.spec-table td { color: var(--muted); }

.channel-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.channel-card {
  padding: 26px; border-radius: var(--radius);
  border: 1px solid var(--line); background: var(--panel);
}
.channel-card .ch-tag {
  display: inline-block; padding: 4px 12px; border-radius: 999px;
  font-family: var(--font-d); font-size: 12px; letter-spacing: 0.1em;
}
.channel-card.stable .ch-tag { background: rgba(53, 240, 224, 0.12); color: var(--cyan); border: 1px solid rgba(53,240,224,.35); }
.channel-card.beta .ch-tag { background: rgba(255, 180, 84, 0.12); color: var(--gold); border: 1px solid rgba(255,180,84,.35); }
.channel-card h3 { font-size: 18px; margin: 12px 0 8px; }
.channel-card p { color: var(--muted); font-size: 14px; }

/* ---------- 历史版本页 ---------- */
.timeline { max-width: 780px; margin: 0 auto; position: relative; }
.timeline::before {
  content: ""; position: absolute; top: 8px; bottom: 8px; left: 15px;
  width: 1px; background: linear-gradient(180deg, var(--cyan), transparent);
  opacity: 0.5;
}
.rel-item {
  position: relative; padding: 0 0 40px 52px;
}
.rel-item::before {
  content: ""; position: absolute; left: 9px; top: 8px;
  width: 13px; height: 13px; border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--cyan);
  box-shadow: 0 0 14px rgba(53, 240, 224, 0.6);
}
.rel-item.latest::before { background: var(--cyan); }
.rel-card {
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--panel);
  padding: 24px 26px;
}
.rel-head { display: flex; align-items: baseline; gap: 14px; flex-wrap: wrap; }
.rel-head .ver { font-family: var(--font-d); font-weight: 700; font-size: 24px; }
.rel-head .ver a { color: var(--txt); text-decoration: none; }
.rel-head .ver a:hover { color: var(--cyan); }
.rel-head .date { font-family: var(--font-d); font-size: 13px; color: var(--muted); letter-spacing: 0.06em; }
.rel-head .pill {
  margin-left: auto; padding: 3px 12px; border-radius: 999px;
  font-family: var(--font-d); font-size: 11px; letter-spacing: 0.12em;
  background: rgba(53, 240, 224, 0.12); color: var(--cyan);
  border: 1px solid rgba(53, 240, 224, 0.35);
}
.rel-card ul { margin: 16px 0 0 18px; color: var(--muted); font-size: 14px; display: grid; gap: 8px; }
.rel-card ul li::marker { color: var(--cyan); }

/* ---------- 通用小工具 ---------- */
.center { text-align: center; }
.mt-16 { margin-top: 16px; } .mt-24 { margin-top: 24px; } .mt-40 { margin-top: 40px; }
.mb-16 { margin-bottom: 16px; } .mb-24 { margin-bottom: 24px; }

/* 响应式 AOS 微调 */
[data-aos] { pointer-events: none; }
[data-aos].aos-animate { pointer-events: auto; }

/* ============================================================
   响应式：PAD（≤1023）/ 手机（≤767）
   ============================================================ */
@media (max-width: 1023px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .sec-split { grid-template-columns: 1fr; gap: 40px; }
  .platforms-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: repeat(2, 1fr); }
  .channel-grid { grid-template-columns: 1fr; }
}

@media (max-width: 767px) {
  .nav-links, .nav-cta { display: none; }
  .nav-burger { display: flex; }
  .section { padding: 64px 18px; }
  .features-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .platforms-grid { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; gap: 26px; }
  .mock-cards { grid-template-columns: 1fr; }
  .mock-site .m-lead { max-width: 100%; }
  .hero { padding-top: calc(var(--nav-h) + 24px); }
  .hero-actions .btn { width: 100%; justify-content: center; }
  .browser-mock { margin-top: 52px; }
  .browser-bar { flex-wrap: wrap; }
  .mock-tabs { display: none; }
  .mock-addr { flex: 1; }
  .cta-banner { padding: 40px 24px; }
  .spec-table th, .spec-table td { padding: 12px 14px; font-size: 13px; }
  .spec-table th { width: 110px; }
  .rel-item { padding-left: 44px; }
  .footer-bottom { justify-content: center; text-align: center; }
}