/* ==========================================================================
   肉联AI · 官网共享设计系统
   配色来源：品牌 Logo 主色 #E7393A（取自小程序太阳码中心图标）
   渐变搭档：#FF8B4E（取自宣传海报暖橙）  淡底：#FDECEC
   零外部依赖：系统字体栈 + 内联 SVG 图标，离线永久可用
   ========================================================================== */

:root{
  /* 品牌三色（主色 + 渐变搭档 + 极淡 tint） */
  --brand:#E7393A;
  --brand-lt:#FF8B4E;
  --brand-bg:#FDECEC;
  --brand-deep:#B92526;

  /* 深色区（Hero / 页脚 / 深色卡） */
  --navy:#141B26;
  --navy-2:#1E2735;
  --navy-3:#2B3648;

  /* 中性 */
  --ink:#161C26;
  --ink-2:#2B3444;
  --sub:#5A6473;
  --gray:#8A93A1;
  --line:#E8EAEF;
  --bg:#FFFFFF;
  --bg-2:#F6F7F9;
  --bg-3:#FBFBFC;

  /* 语义 */
  --ok:#1B9E63;
  --warn:#D98207;

  --radius:12px;
  --radius-lg:18px;
  --shadow:0 6px 20px rgba(20,27,38,.08);
  --shadow-lg:0 18px 48px rgba(20,27,38,.14);
  --maxw:1180px;
}

*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;}
body{
  font-family:"Noto Sans SC","PingFang SC","Microsoft YaHei","Helvetica Neue",Inter,"Source Han Sans SC",sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.75;
  font-size:15px;-webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none;}
img{max-width:100%;height:auto;display:block;}
h1,h2,h3,h4,p,span,b,dd,dt,li{overflow-wrap:break-word;}
ul,ol{list-style:none;}
button{font-family:inherit;cursor:pointer;}
:focus-visible{outline:2px solid var(--brand);outline-offset:3px;border-radius:4px;}

.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px;}

/* ---------- 通用区块 ---------- */
section{padding:88px 0;}
section.alt{background:var(--bg-2);}
section.dark{background:var(--navy);color:#E7EAF0;}
section.tint{background:linear-gradient(180deg,var(--brand-bg) 0%,#fff 100%);}

.sec-head{margin-bottom:44px;max-width:760px;}
.sec-head .bar{width:46px;height:5px;border-radius:3px;background:linear-gradient(135deg,var(--brand),var(--brand-lt));margin-bottom:16px;}
.sec-head h2{font-size:clamp(26px,3.4vw,36px);font-weight:700;line-height:1.3;letter-spacing:-.4px;}
.sec-head h2 small{display:block;font-size:12px;font-weight:500;letter-spacing:2.2px;color:var(--gray);text-transform:uppercase;margin-top:8px;}
.sec-head p{color:var(--sub);margin-top:14px;font-size:16px;}
section.dark .sec-head p{color:#A8B2C2;}
section.dark .sec-head h2 small{color:#7E8CA0;}

.eyebrow{display:inline-block;font-size:12px;letter-spacing:2px;color:var(--brand);font-weight:600;text-transform:uppercase;margin-bottom:12px;}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:12px 26px;border-radius:999px;font-size:15px;font-weight:600;
  border:1px solid transparent;transition:transform .18s ease,box-shadow .18s ease,background .18s ease;
  white-space:nowrap;
}
.btn svg{width:17px;height:17px;stroke:currentColor;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;flex:none;}
.btn-p{background:linear-gradient(135deg,var(--brand) 0%,var(--brand-lt) 100%);color:#fff;box-shadow:0 8px 20px rgba(231,57,58,.28);}
.btn-p:hover{transform:translateY(-2px);box-shadow:0 12px 26px rgba(231,57,58,.36);}
.btn-s{background:#fff;color:var(--ink);border-color:var(--line);box-shadow:var(--shadow);}
.btn-s:hover{transform:translateY(-2px);border-color:var(--brand);color:var(--brand);}
.btn-g{background:rgba(255,255,255,.12);color:#fff;border-color:rgba(255,255,255,.28);}
.btn-g:hover{background:rgba(255,255,255,.2);transform:translateY(-2px);}
.btn-d{background:var(--ink);color:#fff;}
.btn-d:hover{background:var(--ink-2);transform:translateY(-2px);}
.btn-sm{padding:9px 18px;font-size:14px;}

/* ---------- 导航 ---------- */
header{position:sticky;top:0;z-index:100;background:rgba(255,255,255,.86);backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px);border-bottom:1px solid var(--line);}
.nav{display:flex;align-items:center;justify-content:space-between;height:66px;gap:20px;}
.brand{display:flex;align-items:center;gap:10px;flex:none;}
.brand img{width:34px;height:34px;border-radius:9px;}
.brand b{font-size:18px;font-weight:700;letter-spacing:-.2px;}
.brand span{display:block;font-size:11px;color:var(--gray);letter-spacing:1.4px;line-height:1.2;}
.nav-links{display:flex;gap:28px;align-items:center;}
.nav-links a{font-size:14.5px;color:var(--ink-2);font-weight:500;transition:color .16s;}
.nav-links a:hover,.nav-links a.active{color:var(--brand);}
.nav-cta{display:flex;align-items:center;gap:10px;flex:none;}
.nav-toggle{display:none;width:42px;height:42px;border-radius:10px;border:1px solid var(--line);background:#fff;align-items:center;justify-content:center;}
.nav-toggle svg{width:22px;height:22px;stroke:var(--ink);fill:none;stroke-width:2;stroke-linecap:round;}

/* ---------- Hero ---------- */
.hero{
  position:relative;overflow:hidden;color:#fff;
  background:
    radial-gradient(1100px 520px at 88% -10%,rgba(231,57,58,.28),transparent 60%),
    radial-gradient(900px 480px at 4% 108%,rgba(255,139,78,.18),transparent 62%),
    linear-gradient(160deg,#141B26 0%,#1B2432 52%,#141B26 100%);
}
.hero::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:linear-gradient(rgba(255,255,255,.045) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px);
  background-size:56px 56px;
  -webkit-mask-image:radial-gradient(circle at 50% 30%,#000 0%,transparent 78%);
  mask-image:radial-gradient(circle at 50% 30%,#000 0%,transparent 78%);
}
.hero .wrap{position:relative;z-index:2;}
.hero-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:56px;align-items:center;padding:96px 0 84px;}
.hero h1{font-size:clamp(32px,4.6vw,56px);font-weight:700;line-height:1.18;letter-spacing:-1px;}
.hero h1 .hl{background:linear-gradient(120deg,#FF8B4E,#FF5F5F 55%,#E7393A);-webkit-background-clip:text;background-clip:text;color:transparent;}
.hero .lead{font-size:17.5px;color:#B9C2D1;margin:22px 0 14px;max-width:600px;}
.hero .lead b{color:#fff;font-weight:600;}
.hero-kw{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:32px;}
.hero-kw span{
  font-size:12.5px;color:#C7CFDC;background:rgba(255,255,255,.07);
  border:1px solid rgba(255,255,255,.13);padding:5px 12px;border-radius:999px;
}
.hero-cta{display:flex;flex-wrap:wrap;gap:14px;}
.hero-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-top:52px;padding-top:34px;border-top:1px solid rgba(255,255,255,.12);}
.hero-stats b{display:block;font-size:clamp(22px,2.6vw,30px);font-weight:700;color:#fff;line-height:1.15;letter-spacing:-.5px;}
.hero-stats b i{font-style:normal;font-size:.62em;color:var(--brand-lt);margin-left:2px;}
.hero-stats span{font-size:12.5px;color:#8D97A8;display:block;margin-top:4px;}

/* Hero 右侧：设备预览 */
.hero-visual{position:relative;}
.hero-card{
  background:rgba(255,255,255,.97);border-radius:22px;padding:18px 18px 84px;
  box-shadow:0 30px 70px rgba(0,0,0,.42);color:var(--ink);
}
.hero-card .hc-top{display:flex;align-items:center;gap:10px;padding:6px 6px 14px;border-bottom:1px solid var(--line);margin-bottom:14px;}
.hero-card .hc-top img{width:28px;height:28px;border-radius:8px;}
.hero-card .hc-top b{font-size:14px;}
.hero-card .hc-top small{display:block;font-size:11px;color:var(--gray);}
.hero-card .hc-body{display:flex;flex-direction:column;gap:10px;}
.bubble{max-width:88%;padding:11px 14px;border-radius:14px;font-size:13.5px;line-height:1.6;}
.bubble.q{background:var(--brand-bg);color:var(--brand-deep);align-self:flex-end;border-bottom-right-radius:4px;font-weight:500;}
.bubble.a{background:var(--bg-2);color:var(--ink-2);align-self:flex-start;border-bottom-left-radius:4px;}
.bubble .kb{display:flex;justify-content:space-between;padding:5px 0;border-bottom:1px dashed #D9DDE4;font-size:12.5px;}
.bubble .kb:last-child{border-bottom:none;}
.bubble .kb b{color:var(--brand);font-weight:700;}
.hero-visual .qr-float{
  position:absolute;left:-14px;bottom:16px;background:#fff;border-radius:16px;padding:12px;
  box-shadow:var(--shadow-lg);display:flex;gap:10px;align-items:center;z-index:3;
}
.hero-visual .qr-float img{width:62px;height:62px;border-radius:8px;}
.hero-visual .qr-float b{display:block;font-size:13px;}
.hero-visual .qr-float small{font-size:11px;color:var(--sub);}

/* ---------- 能力三卡 ---------- */
.cards-3{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;}
.cards-2{display:grid;grid-template-columns:repeat(2,1fr);gap:22px;}
.card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);padding:28px 26px;
  transition:transform .22s ease,box-shadow .22s ease,border-color .22s ease;
}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:#F3C9C9;}
.card .ico{
  width:46px;height:46px;border-radius:13px;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,var(--brand),var(--brand-lt));margin-bottom:16px;
  box-shadow:0 6px 14px rgba(231,57,58,.24);
}
.card .ico svg{width:23px;height:23px;stroke:#fff;fill:none;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;}
.card h3{font-size:17.5px;font-weight:700;margin-bottom:9px;}
.card p{font-size:14.5px;color:var(--sub);}
.card ul{margin-top:14px;display:flex;flex-direction:column;gap:8px;}
.card ul li{font-size:14px;color:var(--ink-2);padding-left:18px;position:relative;}
.card ul li::before{content:"";position:absolute;left:0;top:9px;width:6px;height:6px;border-radius:50%;background:var(--brand-lt);}

/* ---------- 功能模块（6 大功能） ---------- */
.feature-list{display:flex;flex-direction:column;gap:34px;}
.feature{
  display:grid;grid-template-columns:1fr 1.05fr;gap:40px;align-items:center;
  background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);padding:30px;
  transition:box-shadow .22s ease,border-color .22s ease;
}
.feature:hover{box-shadow:var(--shadow-lg);border-color:#F0CDCD;}
.feature.reverse .f-media{order:-1;}
.f-head{display:flex;align-items:center;gap:12px;margin-bottom:14px;}
.f-num{
  width:44px;height:44px;border-radius:12px;flex:none;display:flex;align-items:center;justify-content:center;
  font-size:16px;font-weight:700;color:#fff;background:linear-gradient(135deg,var(--brand),var(--brand-lt));
  box-shadow:0 6px 14px rgba(231,57,58,.26);letter-spacing:.5px;
}
.f-tag{font-size:12px;letter-spacing:1.6px;color:var(--brand);font-weight:600;text-transform:uppercase;}
.feature h3{font-size:clamp(20px,2.2vw,26px);font-weight:700;line-height:1.35;letter-spacing:-.3px;}
.feature .f-sub{font-size:14.5px;color:var(--sub);margin-top:12px;}
.feature ul{margin-top:16px;display:flex;flex-direction:column;gap:9px;}
.feature ul li{font-size:14.5px;color:var(--ink-2);padding-left:20px;position:relative;}
.feature ul li::before{
  content:"";position:absolute;left:0;top:8px;width:8px;height:8px;border-radius:2px;
  background:linear-gradient(135deg,var(--brand),var(--brand-lt));
}
.f-media{position:relative;}
.f-media video{
  width:100%;display:block;border-radius:14px;background:#0E1520;
  box-shadow:0 14px 36px rgba(20,27,38,.18);
}
.f-poster{position:relative;border-radius:14px;overflow:hidden;box-shadow:0 14px 36px rgba(20,27,38,.18);
  background:linear-gradient(135deg,#F2F5F9 0%,#E4EAF2 100%);}
.f-poster img{width:100%;display:block;}
.f-media video,.vid-thumb video{width:100%;display:block;background:#0E1520;}
.vid-thumb video{height:100%;object-fit:cover;}
.f-poster .play,.vid-thumb .play{
  position:absolute;inset:0;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(180deg,rgba(14,21,32,.12),rgba(14,21,32,.55));
  transition:background .2s;cursor:pointer;
}
.f-poster .play:hover,.vid-thumb .play:hover{background:linear-gradient(180deg,rgba(14,21,32,.2),rgba(14,21,32,.68));}
.f-play{
  width:66px;height:66px;border-radius:50%;background:rgba(255,255,255,.94);
  display:flex;align-items:center;justify-content:center;box-shadow:0 8px 24px rgba(0,0,0,.3);
}
.f-play svg{width:24px;height:24px;fill:var(--brand);stroke:none;margin-left:4px;}
.f-cap{font-size:12.5px;color:var(--gray);margin-top:10px;display:flex;align-items:center;gap:6px;}
.f-cap svg{width:14px;height:14px;stroke:currentColor;fill:none;stroke-width:1.8;flex:none;}

/* ---------- 视频网格 ---------- */
.vid-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;}
.vid-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);overflow:hidden;transition:transform .22s,box-shadow .22s;}
.vid-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);}
.vid-thumb{position:relative;aspect-ratio:16/9;overflow:hidden;
  background:linear-gradient(135deg,#F2F5F9 0%,#E4EAF2 100%);}
.vid-thumb img{width:100%;height:100%;object-fit:cover;}
.vid-thumb .f-play{width:54px;height:54px;}
.vid-thumb .f-play svg{width:20px;height:20px;}
.vid-body{padding:18px 20px 20px;}
.vid-body .f-tag{margin-bottom:8px;}
.vid-body h3{font-size:16.5px;font-weight:700;line-height:1.45;margin-bottom:8px;}
.vid-body p{font-size:13.5px;color:var(--sub);}
.vid-meta{font-size:12px;color:var(--gray);margin-top:12px;padding-top:12px;border-top:1px solid var(--line);display:flex;justify-content:space-between;}

/* ---------- 下载区 ---------- */
.dl-grid{display:grid;grid-template-columns:1fr 1fr;gap:26px;}
.dl-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);padding:32px 30px;
  display:flex;flex-direction:column;position:relative;overflow:hidden;
}
.dl-card::before{content:"";position:absolute;inset:0 0 auto 0;height:4px;background:linear-gradient(90deg,var(--brand),var(--brand-lt));}
.dl-card h3{font-size:20px;font-weight:700;margin-bottom:8px;display:flex;align-items:center;gap:10px;}
.dl-card h3 .pill{font-size:11px;font-weight:600;letter-spacing:1px;padding:3px 9px;border-radius:999px;background:var(--brand-bg);color:var(--brand-deep);}
.dl-card h3 .pill.ok{background:#E4F5EC;color:var(--ok);}
.dl-card h3 .pill.wait{background:#FBF0DC;color:var(--warn);}
.dl-card>p{font-size:14.5px;color:var(--sub);margin-bottom:20px;}
.dl-specs{display:flex;flex-direction:column;gap:9px;margin-bottom:22px;}
.dl-specs div{display:flex;justify-content:space-between;gap:14px;font-size:13.5px;padding-bottom:9px;border-bottom:1px dashed var(--line);}
.dl-specs span{color:var(--gray);}
.dl-specs b{font-weight:600;text-align:right;min-width:0;overflow-wrap:anywhere;}
.dl-actions{margin-top:auto;display:flex;flex-wrap:wrap;gap:12px;align-items:center;}
.dl-note{font-size:12.5px;color:var(--gray);margin-top:14px;}

.qr-panel{
  display:grid;grid-template-columns:auto 1fr;gap:26px;align-items:center;
  background:linear-gradient(135deg,var(--brand-bg),#fff);border:1px solid #F5D5D5;
  border-radius:var(--radius-lg);padding:30px;
}
.qr-panel img{width:190px;height:190px;border-radius:14px;background:#fff;padding:8px;box-shadow:var(--shadow);}
.qr-panel h3{font-size:21px;font-weight:700;margin-bottom:10px;}
.qr-panel p{font-size:14.5px;color:var(--sub);margin-bottom:16px;}
.qr-steps{display:flex;flex-direction:column;gap:10px;}
.qr-steps div{display:flex;gap:11px;align-items:flex-start;font-size:14px;color:var(--ink-2);}
.qr-steps b{
  width:22px;height:22px;border-radius:50%;background:var(--brand);color:#fff;font-size:12px;
  display:flex;align-items:center;justify-content:center;flex:none;margin-top:2px;
}

/* ---------- 数据带 ---------- */
.band{background:linear-gradient(120deg,var(--navy) 0%,#222D3E 55%,var(--navy) 100%);color:#fff;position:relative;overflow:hidden;}
.band::after{content:"";position:absolute;inset:0;background:radial-gradient(700px 300px at 78% 0%,rgba(231,57,58,.2),transparent 62%);pointer-events:none;}
.band .wrap{position:relative;z-index:2;}
.band-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:28px;}
.band-item b{display:block;font-size:clamp(28px,3.4vw,42px);font-weight:700;letter-spacing:-1px;line-height:1.1;color:#fff;}
.band-item b i{font-style:normal;font-size:.55em;color:var(--brand-lt);margin-left:3px;}
.band-item span{font-size:13.5px;color:#96A1B2;display:block;margin-top:8px;}
.band-note{font-size:12px;color:#6E7A8C;margin-top:28px;}

/* ---------- 场景 ---------- */
.scene-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;}
.scene{background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);padding:26px 24px;}
.scene .who{display:inline-block;font-size:12px;font-weight:600;color:var(--brand);background:var(--brand-bg);padding:4px 11px;border-radius:999px;margin-bottom:14px;}
.scene h3{font-size:17px;font-weight:700;margin-bottom:9px;}
.scene p{font-size:14.5px;color:var(--sub);margin-bottom:14px;}
.scene .scene-tags{display:flex;flex-wrap:wrap;gap:7px;}
.scene .scene-tags span{font-size:12.5px;color:var(--ink-2);background:var(--bg-2);border:1px solid var(--line);padding:4px 10px;border-radius:6px;}

/* ---------- 架构 ---------- */
.arch{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;}
.arch-item{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px 20px;}
.arch-item .lvl{font-size:11px;letter-spacing:1.6px;color:var(--brand);font-weight:600;text-transform:uppercase;margin-bottom:8px;}
.arch-item h4{font-size:16px;font-weight:700;margin-bottom:8px;}
.arch-item p{font-size:13.5px;color:var(--sub);}
.arch-item code{font-family:"JetBrains Mono",Consolas,Menlo,monospace;font-size:12.5px;color:var(--brand-deep);background:var(--brand-bg);padding:2px 6px;border-radius:4px;}

/* ---------- FAQ ---------- */
.faq{max-width:860px;margin:0 auto;}
.faq details{border:1px solid var(--line);border-radius:var(--radius);background:#fff;margin-bottom:12px;overflow:hidden;transition:border-color .2s;}
.faq details[open]{border-color:#F2CACA;}
.faq summary{
  padding:18px 22px;font-size:15.5px;font-weight:600;cursor:pointer;list-style:none;
  display:flex;justify-content:space-between;gap:16px;align-items:center;
}
.faq summary::-webkit-details-marker{display:none;}
.faq summary::after{content:"+";font-size:22px;color:var(--brand);font-weight:400;line-height:1;flex:none;}
.faq details[open] summary::after{content:"−";}
.faq .ans{padding:0 22px 20px;font-size:14.5px;color:var(--sub);}
.faq .ans b{color:var(--ink);font-weight:600;}

/* ---------- CTA ---------- */
.cta-band{background:linear-gradient(135deg,var(--brand) 0%,var(--brand-lt) 100%);color:#fff;position:relative;overflow:hidden;}
.cta-band::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(600px 300px at 88% 20%,rgba(255,255,255,.2),transparent 60%);
}
.cta-inner{position:relative;z-index:2;display:grid;grid-template-columns:1fr auto;gap:36px;align-items:center;}
.cta-inner h2{font-size:clamp(24px,3.2vw,34px);font-weight:700;line-height:1.35;letter-spacing:-.4px;}
.cta-inner p{margin-top:12px;font-size:15.5px;opacity:.94;max-width:600px;}
.cta-actions{display:flex;flex-wrap:wrap;gap:14px;}

/* ---------- 页脚 ---------- */
footer{background:var(--navy);color:#8D97A8;padding:56px 0 26px;font-size:13.5px;}
.foot-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:36px;margin-bottom:38px;}
.foot-brand{display:flex;align-items:center;gap:10px;margin-bottom:14px;}
.foot-brand img{width:34px;height:34px;border-radius:9px;}
.foot-brand b{color:#fff;font-size:17px;}
.foot-col h4{color:#fff;font-size:14.5px;font-weight:600;margin-bottom:13px;}
.foot-col a{display:block;color:#8D97A8;font-size:13.5px;padding:4px 0;transition:color .16s;}
.foot-col a:hover{color:#fff;}
.foot-col p{padding:3px 0;}
.foot-bottom{border-top:1px solid rgba(255,255,255,.1);padding-top:20px;display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;font-size:12.5px;color:#6E7A8C;}
.foot-bottom a{color:#6E7A8C;}
.foot-bottom a:hover{color:#B9C2D1;}

/* ---------- 面包屑 / 页面头 ---------- */
.page-head{padding:56px 0 44px;background:var(--bg-2);border-bottom:1px solid var(--line);}
.page-head h1{font-size:clamp(28px,4vw,44px);font-weight:700;line-height:1.22;letter-spacing:-.8px;}
.page-head p{color:var(--sub);font-size:16px;margin-top:14px;max-width:760px;}
.crumb{font-size:13px;color:var(--gray);margin-bottom:14px;}
.crumb a{color:var(--brand);}

/* ---------- 滚动揭示（稳健兜底：JS 未执行时内容必须可见） ----------
   关键：只有当 site.js 成功加载并加上 html.rv-ready 后才启用隐藏态。
   JS 缺失/报错/IO 未触发时，内容始终可见，绝不出现整页空白。 */
.rv{opacity:1;transform:none;}
html.rv-ready .rv{opacity:0;transform:translateY(22px);transition:opacity .6s ease,transform .6s ease;}
html.rv-ready .rv.in{opacity:1;transform:none;}

/* ---------- 响应式 ---------- */
@media (max-width:1080px){
  .hero-grid{grid-template-columns:1fr;gap:40px;}
  .hero-visual{max-width:520px;}
  .arch{grid-template-columns:repeat(2,1fr);}
  .foot-grid{grid-template-columns:1fr 1fr;gap:28px;}
}
@media (max-width:920px){
  .cards-3,.vid-grid,.scene-grid{grid-template-columns:repeat(2,1fr);}
  .cards-2{gap:18px;}
  .feature,.feature.reverse{grid-template-columns:1fr;gap:24px;}
  .feature.reverse .f-media{order:0;}
  .dl-grid{grid-template-columns:1fr;}
  .hero-stats{grid-template-columns:repeat(2,1fr);gap:22px;}
  .band-grid{grid-template-columns:repeat(2,1fr);}
  .cta-inner{grid-template-columns:1fr;}
}
@media (max-width:760px){
  /* 移动端正文与标签统一提升到 13px 下限，保证可读性 */
  .eyebrow,.f-tag,.brand span,.hero-stats span,.band-note,.band-item span,
  .foot-brand span,.vid-body .f-tag,.f-cap,.dl-note,.scene .who,.hero-visual .qr-float small,
  .foot-col p,.foot-bottom,.hero-card .hc-top small{font-size:13px;}
  .dl-card h3 .pill{font-size:12px;}
  .nav-links{
    display:none;position:absolute;top:66px;left:0;right:0;background:#fff;
    flex-direction:column;align-items:stretch;gap:0;padding:8px 24px 18px;
    border-bottom:1px solid var(--line);box-shadow:var(--shadow);
  }
  .nav-links.open{display:flex;}
  .nav-links a{padding:12px 0;border-bottom:1px solid var(--bg-2);font-size:15px;}
  .nav-links a:last-child{border-bottom:none;}
  .nav-toggle{display:flex;}
  .nav-cta .btn{display:none;}
  section{padding:64px 0;}
  .cards-3,.vid-grid,.scene-grid,.arch{grid-template-columns:1fr;}
  .cards-2{grid-template-columns:1fr;}
  .qr-panel{grid-template-columns:1fr;text-align:center;}
  .qr-panel img{margin:0 auto;}
  .qr-steps{align-items:flex-start;}
  .hero-grid{padding:64px 0 56px;}
  .hero-visual .qr-float{position:static;margin-top:16px;display:inline-flex;}
  .hero-visual{text-align:center;}
  .hero-card .hc-body{align-items:center;}
  .bubble{max-width:100%;}
  .foot-grid{grid-template-columns:1fr;}
  .dl-card{padding:26px 22px;}
}
@media (max-width:420px){
  .hero-stats{grid-template-columns:1fr 1fr;}
  .band-grid{grid-template-columns:1fr 1fr;}
  .wrap{padding:0 18px;}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto;}
  .rv{opacity:1;transform:none;transition:none;}
  *{animation-duration:.01ms !important;transition-duration:.01ms !important;}
}