/* ============================================================
   三众娱乐直播公会系统 · 宣传官网
   黑金设计系统（与系统 UI 同色系：哑金 #C9A557 / 亮金 #E8C877 / 深黑紫 #17121F）
   ============================================================ */
:root {
  color-scheme: dark; /* 原生表单控件（select 下拉/日期等）按深色渲染 */
  --gold: #C9A557;
  --gold-bright: #E8C877;
  --gold-deep: #A8863C;
  --bg-deep: #0B0810;
  --bg: #120E1A;
  --bg-2: #17121F;
  --card: rgba(255, 255, 255, 0.035);
  --card-hover: rgba(255, 255, 255, 0.06);
  --line: rgba(201, 165, 87, 0.18);
  --line-soft: rgba(255, 255, 255, 0.08);
  --text: #EDE7DA;
  --text-sub: #B9B2A6;
  --text-muted: #8E8779;
  --gold-grad: linear-gradient(135deg, #B8860B 0%, #E8C877 45%, #C9A557 100%);
  --shadow-lg: 0 24px 64px rgba(0, 0, 0, 0.55);
  --radius: 14px;
  --nav-h: 72px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.75;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
.container { width: min(1200px, 92%); margin: 0 auto; }
.gold-text {
  background: var(--gold-grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ============ 顶部导航 ============ */
.nav {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  height: var(--nav-h);
  background: rgba(11, 8, 16, 0.72);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line-soft);
  transition: background 0.3s;
}
.nav-inner { height: var(--nav-h); display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: flex; align-items: center; gap: 14px; flex-shrink: 0; }
.brand img { height: 38px; width: auto; }
.brand .brand-div { width: 1px; height: 26px; background: linear-gradient(180deg, transparent, var(--gold-deep), transparent); }
.brand .brand-name { font-size: 16px; font-weight: 800; letter-spacing: 2px; color: var(--gold-bright); white-space: nowrap; line-height: 1.3; }
.brand .brand-name small { display: block; font-size: 9px; font-weight: 400; color: var(--text-muted); letter-spacing: 3.2px; margin-top: 3px; }
.nav-links { display: flex; align-items: center; gap: 4px; }
.nav-links a {
  position: relative; padding: 8px 13px; font-size: 15px; color: var(--text-sub);
  border-radius: 8px; transition: color 0.2s; white-space: nowrap;
}
.nav-links a:hover { color: var(--gold-bright); }
.nav-links a[aria-current="page"] { color: var(--gold-bright); font-weight: 600; }
.nav-links a[aria-current="page"]::after {
  content: ""; position: absolute; left: 13px; right: 13px; bottom: 2px; height: 2px;
  background: var(--gold-grad); border-radius: 2px;
}
.nav-cta { display: flex; align-items: center; gap: 14px; flex-shrink: 0; }
.nav-phone { display: flex; align-items: center; gap: 7px; color: var(--gold-bright); font-size: 15px; font-weight: 600; white-space: nowrap; }
.nav-phone svg { width: 16px; height: 16px; }
.nav-burger {
  display: none; width: 42px; height: 42px; border: 1px solid var(--line); border-radius: 10px;
  background: transparent; cursor: pointer; flex-direction: column; align-items: center; justify-content: center; gap: 5px;
}
.nav-burger span { display: block; width: 18px; height: 2px; background: var(--gold); border-radius: 2px; transition: 0.25s; }
.nav-burger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-burger.open span:nth-child(2) { opacity: 0; }
.nav-burger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
.mobile-menu {
  display: none; position: fixed; top: var(--nav-h); left: 0; right: 0; z-index: 99;
  background: rgba(13, 10, 19, 0.97); backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--line); padding: 12px 4% 22px;
}
.mobile-menu.open { display: block; }
.mobile-menu a { display: block; padding: 13px 10px; font-size: 16px; color: var(--text-sub); border-bottom: 1px solid rgba(255,255,255,0.05); }
.mobile-menu a[aria-current="page"] { color: var(--gold-bright); }

/* ============ 按钮 ============ */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 30px; border-radius: 999px; font-size: 16px; font-weight: 600;
  letter-spacing: 1px; cursor: pointer; border: none; transition: 0.25s; white-space: nowrap;
}
.btn-gold { background: var(--gold-grad); color: #17121F; box-shadow: 0 8px 28px rgba(201, 165, 87, 0.35); }
.btn-gold:hover { transform: translateY(-2px); box-shadow: 0 12px 36px rgba(201, 165, 87, 0.5); }
.btn-line { background: transparent; color: var(--gold-bright); border: 1px solid var(--line); }
.btn-line:hover { border-color: var(--gold); background: rgba(201, 165, 87, 0.08); }
.btn-sm { padding: 9px 22px; font-size: 14px; }

/* ============ 区块 ============ */
.section { padding: 96px 0; position: relative; }
.section-tight { padding: 64px 0; }
.sec-head { text-align: center; max-width: 780px; margin: 0 auto 56px; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 13px; letter-spacing: 4px; color: var(--gold); font-weight: 600;
  text-transform: uppercase; margin-bottom: 18px;
}
.eyebrow::before, .eyebrow::after { content: ""; width: 28px; height: 1px; background: var(--gold-deep); }
.sec-head h2 { font-size: clamp(26px, 3.4vw, 40px); font-weight: 700; letter-spacing: 1px; line-height: 1.35; }
.sec-head .sub { margin-top: 16px; color: var(--text-sub); font-size: 16px; }
.breadcrumb { padding: calc(var(--nav-h) + 26px) 0 10px; font-size: 13px; color: var(--text-muted); }
.breadcrumb a:hover { color: var(--gold-bright); }
.breadcrumb .sep { margin: 0 8px; color: var(--text-muted); }

/* ============ 页头横幅（子页） ============ */
.page-hero { position: relative; padding: calc(var(--nav-h) + 64px) 0 72px; overflow: hidden; }
.page-hero .bg { position: absolute; inset: 0; object-fit: cover; width: 100%; height: 100%; opacity: 0.55; z-index: -2; }
.page-hero::after {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: linear-gradient(180deg, rgba(11,8,16,0.55) 0%, var(--bg) 96%);
}
.page-hero h1 { font-size: clamp(30px, 4vw, 46px); font-weight: 700; letter-spacing: 2px; }
.page-hero .lead { margin-top: 18px; max-width: 720px; color: var(--text-sub); font-size: 17px; }

/* ============ 首页 Hero ============ */
.hero { position: relative; min-height: 92vh; display: flex; align-items: center; padding: calc(var(--nav-h) + 40px) 0 90px; overflow: hidden; }
.hero .bg { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; z-index: -2; opacity: 0.85; }
.hero::after {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: radial-gradient(ellipse 70% 55% at 50% 38%, rgba(23,18,31,0.10) 0%, rgba(11,8,16,0.62) 62%, var(--bg-deep) 100%);
}
.hero-inner { text-align: center; max-width: 900px; margin: 0 auto; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 9px; padding: 8px 20px; margin-bottom: 30px;
  border: 1px solid var(--line); border-radius: 999px; background: rgba(201,165,87,0.08);
  color: var(--gold-bright); font-size: 13.5px; letter-spacing: 2px;
}
.hero-badge .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--gold-bright); box-shadow: 0 0 10px var(--gold-bright); animation: pulse 2s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: 0.35; } }
.hero h1 { font-size: clamp(34px, 5vw, 60px); font-weight: 800; letter-spacing: 3px; line-height: 1.3; }
.hero .hero-sub { margin-top: 22px; font-size: clamp(15px, 1.6vw, 19px); color: var(--text-sub); letter-spacing: 2px; }
.hero-actions { margin-top: 44px; display: flex; gap: 18px; justify-content: center; flex-wrap: wrap; }
.hero-stats { margin-top: 66px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.hero-stat { padding: 18px 8px; border-top: 1px solid var(--line); }
.hero-stat b { display: block; font-size: clamp(24px, 3vw, 38px); font-weight: 800; letter-spacing: 1px; }
.hero-stat > span { display: block; margin-top: 4px; font-size: 13px; color: var(--text-muted); letter-spacing: 1px; }

/* ============ 网格与卡片 ============ */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.card {
  background: var(--card); border: 1px solid var(--line-soft); border-radius: var(--radius);
  padding: 30px 26px; transition: 0.3s; position: relative; overflow: hidden;
}
.card:hover { background: var(--card-hover); border-color: var(--line); transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.card .icon {
  width: 52px; height: 52px; border-radius: 13px; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(150deg, rgba(201,165,87,0.16), rgba(201,165,87,0.05));
  border: 1px solid var(--line); margin-bottom: 20px;
}
.card .icon svg { width: 26px; height: 26px; color: var(--gold-bright); }
.card h3 { font-size: 19px; font-weight: 700; letter-spacing: 0.5px; margin-bottom: 12px; }
.card h3 .idx { font-size: 13px; color: var(--gold); margin-right: 8px; font-weight: 600; }
.card p { font-size: 14.5px; color: var(--text-sub); }
.card .more { display: inline-flex; align-items: center; gap: 6px; margin-top: 16px; font-size: 14px; color: var(--gold); font-weight: 600; }
.card .more:hover { color: var(--gold-bright); }

/* 亮点列表（金色对勾/序号条目） */
.ticks li { position: relative; padding-left: 30px; margin-bottom: 13px; color: var(--text-sub); font-size: 15px; }
.ticks li::before {
  content: ""; position: absolute; left: 2px; top: 9px; width: 14px; height: 14px;
  background: var(--gold-grad); border-radius: 4px;
  -webkit-mask: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="3.4" stroke-linecap="round" stroke-linejoin="round"><path d="M20 6 9 17l-5-5"/></svg>') center/contain no-repeat;
  mask: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="3.4" stroke-linecap="round" stroke-linejoin="round"><path d="M20 6 9 17l-5-5"/></svg>') center/contain no-repeat;
}
.ticks li b { color: var(--text); font-weight: 700; }

/* ============ 截图展示框（浏览器窗体） ============ */
.shot-frame {
  border-radius: 14px; overflow: hidden; border: 1px solid var(--line);
  background: #1A1425; box-shadow: var(--shadow-lg);
}
.shot-bar {
  display: flex; align-items: center; gap: 10px; padding: 11px 16px;
  background: rgba(255,255,255,0.04); border-bottom: 1px solid var(--line-soft);
}
.shot-bar .dots { display: flex; gap: 6px; }
.shot-bar .dots i { width: 10px; height: 10px; border-radius: 50%; background: rgba(255,255,255,0.14); }
.shot-bar .dots i:first-child { background: rgba(232,110,110,0.55); }
.shot-bar .dots i:nth-child(2) { background: rgba(232,200,119,0.5); }
.shot-bar .dots i:nth-child(3) { background: rgba(120,200,140,0.5); }
.shot-bar .url {
  flex: 1; max-width: 420px; margin: 0 auto; padding: 4px 14px; text-align: center;
  background: rgba(0,0,0,0.35); border-radius: 999px; font-size: 12px; color: var(--text-muted); letter-spacing: 0.5px;
}
.shot-frame img { width: 100%; }
figcaption.shot-cap, .shot-cap { margin-top: 14px; text-align: center; font-size: 13px; color: var(--text-muted); letter-spacing: 1px; }

/* ============ 手机壳 ============ */
.phone-frame {
  width: min(250px, 74vw); border-radius: 34px; border: 1px solid rgba(201,165,87,0.35);
  background: #060409; padding: 9px; box-shadow: 0 22px 55px rgba(0,0,0,0.6), inset 0 0 0 1px rgba(255,255,255,0.05);
  position: relative;
}
.phone-frame::before {
  content: ""; position: absolute; top: 9px; left: 50%; transform: translateX(-50%);
  width: 42%; height: 20px; background: #060409; border-radius: 0 0 14px 14px; z-index: 2;
}
.phone-frame img { border-radius: 26px; width: 100%; }

/* ============ 流程链（金色节点） ============ */
.flow-chain { display: flex; align-items: stretch; justify-content: center; flex-wrap: wrap; gap: 10px; }
.flow-chain .node {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  min-width: 118px; padding: 16px 20px; border-radius: 12px; text-align: center;
  background: linear-gradient(160deg, rgba(38,32,48,0.92), rgba(24,20,32,0.96));
  border: 1px solid var(--line); position: relative;
}
.flow-chain .node b { font-size: 16px; color: var(--gold-bright); letter-spacing: 1px; }
.flow-chain .node span { font-size: 12px; color: var(--text-muted); margin-top: 4px; }
.flow-chain .arrow { display: flex; align-items: center; color: var(--gold-deep); font-size: 20px; }
.flow-chain .arrow svg { width: 20px; height: 20px; }

/* ============ 数字统计带 ============ */
.stat-band { border-top: 1px solid var(--line-soft); border-bottom: 1px solid var(--line-soft); background: rgba(201,165,87,0.04); }
.stat-band .grid-4 { gap: 10px; }
.stat b { display: block; font-size: clamp(30px, 3.6vw, 46px); font-weight: 800; letter-spacing: 1px; }
.stat > span { display: block; margin-top: 6px; color: var(--text-sub); font-size: 14px; letter-spacing: 1px; }

/* ============ 图文分栏 ============ */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.split.rev .split-media { order: 2; }
.split-media .shot-frame { transform: perspective(1400px) rotateY(-4deg); transition: 0.5s; }
.split.rev .split-media .shot-frame { transform: perspective(1400px) rotateY(4deg); }
.split-media .shot-frame:hover { transform: none; }
.split-body .eyebrow { margin-bottom: 14px; }
.split-body h2 { font-size: clamp(24px, 2.6vw, 34px); font-weight: 700; letter-spacing: 1px; margin-bottom: 20px; line-height: 1.4; }
.split-body p { color: var(--text-sub); margin-bottom: 18px; }

/* ============ 表格 ============ */
.tbl-wrap { overflow-x: auto; border: 1px solid var(--line-soft); border-radius: var(--radius); background: var(--card); }
table.tbl { width: 100%; border-collapse: collapse; min-width: 640px; }
.tbl th {
  text-align: left; padding: 15px 20px; font-size: 14px; letter-spacing: 1px; color: var(--gold-bright);
  background: rgba(201,165,87,0.08); border-bottom: 1px solid var(--line); white-space: nowrap;
}
.tbl td { padding: 14px 20px; font-size: 14.5px; color: var(--text-sub); border-bottom: 1px solid rgba(255,255,255,0.05); vertical-align: top; }
.tbl tr:last-child td { border-bottom: none; }
.tbl td:first-child { color: var(--text); font-weight: 600; white-space: nowrap; }

/* ============ FAQ ============ */
.faq details {
  border: 1px solid var(--line-soft); border-radius: 12px; background: var(--card);
  margin-bottom: 14px; overflow: hidden; transition: 0.25s;
}
.faq details[open] { border-color: var(--line); background: var(--card-hover); }
.faq summary {
  cursor: pointer; list-style: none; padding: 19px 56px 19px 24px;
  font-size: 16.5px; font-weight: 600; color: var(--text); position: relative;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; position: absolute; right: 22px; top: 50%; transform: translateY(-50%);
  font-size: 24px; font-weight: 300; color: var(--gold); transition: 0.25s;
}
.faq details[open] summary::after { content: "−"; }
.faq .faq-a { padding: 0 24px 22px; color: var(--text-sub); font-size: 15px; }

/* ============ 报价卡 ============ */
.price-card {
  background: linear-gradient(165deg, rgba(38,32,48,0.9), rgba(22,18,29,0.96));
  border: 1px solid var(--line); border-radius: 18px; padding: 38px 34px; position: relative;
  display: flex; flex-direction: column;
}
.price-card.hot { border-color: rgba(232,200,119,0.55); box-shadow: 0 0 0 1px rgba(232,200,119,0.25), 0 26px 70px rgba(201,165,87,0.14); }
.price-tag {
  position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  padding: 5px 22px; border-radius: 999px; background: var(--gold-grad);
  color: #17121F; font-size: 13px; font-weight: 700; letter-spacing: 2px; white-space: nowrap;
}
.price-card .mode { font-size: 13px; letter-spacing: 3px; color: var(--gold); font-weight: 700; }
.price-card h3 { font-size: 24px; font-weight: 800; margin: 8px 0 4px; letter-spacing: 1px; }
.price-card .mode-desc { font-size: 13.5px; color: var(--text-muted); margin-bottom: 20px; }
.price-card .price { display: flex; align-items: baseline; gap: 6px; margin-bottom: 6px; }
.price-card .price .num { font-size: clamp(34px, 3.4vw, 46px); font-weight: 800; letter-spacing: 0; }
.price-card .price .unit { color: var(--text-muted); font-size: 14px; }
.price-card .price-note { font-size: 13px; color: var(--text-muted); margin-bottom: 22px; }
.price-card ul { margin: 4px 0 26px; flex: 1; }
.price-card ul li { position: relative; padding: 9px 0 9px 28px; font-size: 14.5px; color: var(--text-sub); border-bottom: 1px dashed rgba(255,255,255,0.07); }
.price-card ul li::before {
  content: ""; position: absolute; left: 4px; top: 16px; width: 13px; height: 13px;
  background: var(--gold); border-radius: 50%;
  -webkit-mask: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="3.4" stroke-linecap="round" stroke-linejoin="round"><path d="M20 6 9 17l-5-5"/></svg>') center/contain no-repeat;
  mask: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="3.4" stroke-linecap="round" stroke-linejoin="round"><path d="M20 6 9 17l-5-5"/></svg>') center/contain no-repeat;
}
.price-card ul li b { color: var(--text); }
.price-card .btn { width: 100%; }

/* 报价双卡布局（独立安装版 + SaaS 列） */
.plans-grid { display: grid; grid-template-columns: 1.15fr 1fr; gap: 30px; align-items: stretch; }
.plans-grid > div:last-child { display: grid; gap: 30px; align-content: start; }
@media (max-width: 960px) {
  .plans-grid { grid-template-columns: 1fr; }
}

/* ============ CTA 大条 ============ */
.cta-band {
  position: relative; overflow: hidden; text-align: center;
  border: 1px solid var(--line); border-radius: 22px; padding: 70px 8%;
  background:
    radial-gradient(ellipse 60% 90% at 50% 0%, rgba(201,165,87,0.13), transparent 65%),
    linear-gradient(165deg, rgba(38,32,48,0.85), rgba(18,14,26,0.95));
}
.cta-band h2 { font-size: clamp(24px, 3vw, 36px); font-weight: 800; letter-spacing: 2px; }
.cta-band p { margin: 16px auto 34px; max-width: 620px; color: var(--text-sub); }
.cta-band .cta-contacts { margin-top: 26px; display: flex; gap: 26px; justify-content: center; flex-wrap: wrap; color: var(--text-sub); font-size: 14.5px; }
.cta-band .cta-contacts b { color: var(--gold-bright); font-weight: 600; }

/* 下拉选项：深底浅字（部分浏览器原生白底会盖过继承色） */
select option, select optgroup {
  background-color: #1A1425;
  color: var(--text);
}

/* ============ 双列联系卡 ============ */
.contact-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 26px; }
.contact-item {
  display: flex; gap: 18px; padding: 26px; border: 1px solid var(--line-soft);
  border-radius: var(--radius); background: var(--card); transition: 0.3s; align-items: flex-start;
}
.contact-item:hover { border-color: var(--line); background: var(--card-hover); }
.contact-item .icon {
  flex-shrink: 0; width: 50px; height: 50px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
  background: rgba(201,165,87,0.1); border: 1px solid var(--line);
}
.contact-item .icon svg { width: 24px; height: 24px; color: var(--gold-bright); }
.contact-item h3 { font-size: 15px; color: var(--text-muted); font-weight: 400; letter-spacing: 1px; }
.contact-item p { font-size: 18px; font-weight: 700; color: var(--text); margin-top: 3px; }
.contact-item p small { display: block; font-size: 13px; font-weight: 400; color: var(--text-muted); margin-top: 4px; }
.contact-item a:hover { color: var(--gold-bright); }

/* ============ 页脚 ============ */
.footer { background: #0A070E; border-top: 1px solid var(--line-soft); padding: 64px 0 0; margin-top: 40px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.3fr; gap: 40px; padding-bottom: 46px; }
.footer h4 { font-size: 15px; letter-spacing: 2px; color: var(--gold-bright); margin-bottom: 20px; font-weight: 600; }
.footer .about p { font-size: 13.5px; color: var(--text-muted); line-height: 2; }
.footer .about img { height: 38px; width: auto; margin-bottom: 16px; }
.footer li { margin-bottom: 11px; }
.footer li a { font-size: 14px; color: var(--text-sub); transition: 0.2s; }
.footer li a:hover { color: var(--gold-bright); }
.footer .f-contact li { display: flex; gap: 9px; font-size: 13.5px; color: var(--text-sub); line-height: 1.9; }
.footer .f-contact svg { width: 15px; height: 15px; flex-shrink: 0; margin-top: 6px; color: var(--gold); }
.footer .f-qr { display: flex; gap: 16px; margin-top: 18px; align-items: center; }
.footer .f-qr img { width: 86px; height: 86px; border-radius: 10px; border: 1px solid var(--line); }
.footer .f-qr p { font-size: 12.5px; color: var(--text-muted); line-height: 1.8; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.05); padding: 20px 0; }
.footer-bottom .container { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; font-size: 12.5px; color: var(--text-muted); }
.footer-bottom a { color: var(--text-muted); }
.footer-bottom a:hover { color: var(--gold-bright); }

/* 返回顶部 */
.back-top {
  position: fixed; right: 26px; bottom: 30px; z-index: 90; width: 46px; height: 46px;
  border-radius: 50%; border: 1px solid var(--line); background: rgba(23,18,31,0.9);
  color: var(--gold-bright); display: flex; align-items: center; justify-content: center;
  cursor: pointer; opacity: 0; pointer-events: none; transition: 0.3s; backdrop-filter: blur(8px);
}
.back-top.show { opacity: 1; pointer-events: auto; }
.back-top:hover { background: var(--gold); color: #17121F; }
.back-top svg { width: 20px; height: 20px; }

/* ============ 滚动进场动画 ============ */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.in { opacity: 1; transform: none; }
.reveal.d1 { transition-delay: 0.1s; } .reveal.d2 { transition-delay: 0.2s; } .reveal.d3 { transition-delay: 0.3s; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ============ 响应式 ============ */
@media (max-width: 1080px) {
  .nav-links, .nav-phone { display: none; }
  .nav-burger { display: flex; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 860px) {
  .section { padding: 64px 0; }
  .grid-2, .grid-3, .split, .contact-grid { grid-template-columns: 1fr; }
  .split { gap: 36px; }
  .split.rev .split-media { order: 0; }
  .hero { min-height: auto; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); gap: 4px; }
  .price-card { padding: 32px 24px; }
  .flow-chain { flex-direction: column; align-items: stretch; }
  .flow-chain .arrow { transform: rotate(90deg); justify-content: center; }
}
@media (max-width: 560px) {
  .grid-4 { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .btn { padding: 12px 24px; font-size: 15px; }
  /* 小屏导航精简：只留 logo + 汉堡，CTA 移入抽屉 */
  .brand .brand-name, .brand .brand-div { display: none; }
  .brand img { height: 34px; width: auto; }
  .nav-cta .btn { display: none; }
}
.mobile-menu .m-cta {
  display: flex; align-items: center; gap: 9px; margin-top: 14px; padding: 13px 12px;
  border: 1px solid var(--line); border-radius: 12px; text-align: center;
  color: var(--gold-bright); font-weight: 700; justify-content: center; border-bottom: 1px solid var(--line);
}