:root {
      --bg:#080611; --panel:rgba(255,255,255,.08); --text:#fff; --muted:#d8d4e4;
      --pink:#ff3d91; --violet:#8b5cf6; --cyan:#37d5ff; --safe-bottom:env(safe-area-inset-bottom,0px);
    }
    *{box-sizing:border-box} html{scroll-behavior:smooth;background:var(--bg)}
    body{margin:0;background:radial-gradient(circle at 20% 5%,#28103d 0,transparent 32%),radial-gradient(circle at 85% 22%,#102c49 0,transparent 28%),var(--bg);color:var(--text);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;overflow-x:hidden}
    button,a{font:inherit} a{text-decoration:none;color:inherit}
    .hero{position:relative;min-height:100svh;display:grid;place-items:end center;isolation:isolate;overflow:hidden;padding:clamp(24px,5vw,64px) 20px calc(112px + var(--safe-bottom))}
    .hero video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:-3;filter:saturate(.94) contrast(1.03)}
    .hero::before{content:"";position:absolute;inset:0;z-index:-2;background:linear-gradient(180deg,rgba(7,5,14,.18) 0%,rgba(7,5,14,.28) 35%,rgba(7,5,14,.88) 82%,#080611 100%)}
    .hero::after{content:"";position:absolute;width:60vw;height:60vw;border-radius:50%;background:rgba(255,55,145,.22);filter:blur(90px);right:-30vw;bottom:-25vw;z-index:-1}
    .hero-content{width:min(760px,100%);text-align:center;animation:rise .8s ease-out both}
    html[lang="zh-CN"] .eyebrow{letter-spacing:.04em;text-transform:none}
    .eyebrow{display:inline-flex;align-items:center;gap:8px;padding:8px 13px;border:1px solid rgba(255,255,255,.25);border-radius:999px;background:rgba(7,5,14,.35);backdrop-filter:blur(12px);font-size:clamp(11px,2.6vw,14px);font-weight:700;letter-spacing:.08em;text-transform:uppercase}
    .dot{width:8px;height:8px;border-radius:50%;background:#45ef8b;box-shadow:0 0 16px #45ef8b}
    h1{margin:16px auto 10px;font-size:clamp(42px,10vw,92px);line-height:.94;letter-spacing:-.055em;max-width:820px;text-wrap:balance}
    .lead{margin:0 auto 22px;color:var(--muted);font-size:clamp(16px,4vw,22px);line-height:1.5;max-width:610px;text-wrap:balance}
    .download{display:inline-flex;justify-content:center;align-items:center;gap:10px;width:min(420px,100%);min-height:62px;padding:16px 24px;border-radius:999px;background:linear-gradient(100deg,var(--pink),var(--violet));box-shadow:0 16px 44px rgba(238,47,137,.38),inset 0 1px rgba(255,255,255,.28);font-size:clamp(17px,4vw,21px);font-weight:850;letter-spacing:-.02em;position:relative;overflow:hidden;transition:transform .2s ease,filter .2s ease}
    .download:hover{transform:translateY(-2px) scale(1.015);filter:brightness(1.08)} .download:active{transform:scale(.98)}
    .download::after{content:"";position:absolute;inset:-40% auto -40% -35%;width:28%;transform:rotate(18deg);background:linear-gradient(90deg,transparent,rgba(255,255,255,.48),transparent);animation:shine 3s infinite}
    .micro{margin:12px 0 0;color:rgba(255,255,255,.64);font-size:clamp(11px,2.7vw,13px)}
    main{padding-bottom:112px}.section{width:min(1180px,100%);margin:auto;padding:clamp(64px,10vw,120px) 18px}
    .section-head{text-align:center;max-width:760px;margin:0 auto clamp(28px,6vw,54px)}
    .section h2{margin:0 0 12px;font-size:clamp(32px,7vw,62px);line-height:1.02;letter-spacing:-.045em;text-wrap:balance}
    .section p{margin:0;color:var(--muted);font-size:clamp(15px,3.8vw,20px);line-height:1.6}
    .features{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
    .feature{padding:clamp(21px,4vw,34px);border:1px solid rgba(255,255,255,.12);background:linear-gradient(145deg,rgba(255,255,255,.1),rgba(255,255,255,.045));border-radius:26px;backdrop-filter:blur(16px)}
    .icon{display:grid;place-items:center;width:48px;height:48px;border-radius:16px;background:linear-gradient(135deg,rgba(255,61,145,.28),rgba(139,92,246,.28));font-size:24px;margin-bottom:17px}
    .feature h3{margin:0 0 8px;font-size:clamp(19px,4vw,25px)}.feature p{font-size:clamp(14px,3vw,17px)}
    .gallery-stack{display:grid;gap:10px;overflow:hidden}
    .gallery-wrap{overflow:hidden;mask-image:linear-gradient(90deg,transparent,#000 6%,#000 94%,transparent)}
    .gallery{display:flex;gap:14px;width:max-content;padding:8px 0 12px;will-change:transform}
    .gallery-left,.gallery-right{animation:none}
    .card{width:clamp(190px,32vw,310px);height:clamp(300px,52vw,470px);border-radius:28px;overflow:hidden;position:relative;flex:none;background:#151020;box-shadow:0 20px 55px rgba(0,0,0,.35)}
    .card img{width:100%;height:100%;object-fit:cover;transition:transform .7s ease}.card:hover img{transform:scale(1.045)}
    .card::after{content:"";position:absolute;inset:auto 0 0;height:36%;background:linear-gradient(transparent,rgba(6,4,11,.75))}
    .cta{margin:0 18px clamp(26px,6vw,70px);min-height:clamp(440px,72vw,650px);border-radius:34px;overflow:hidden;position:relative;display:grid;place-items:end center;padding:32px 22px 48px;text-align:center;background:#171020;isolation:isolate}
    .cta img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:-3}.cta::before{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(7,5,14,.05),rgba(7,5,14,.88));z-index:-2}
    .cta-content{max-width:650px}.cta h2{font-size:clamp(37px,8vw,70px);line-height:1;letter-spacing:-.05em;margin:0 0 13px;text-wrap:balance}.cta p{font-size:clamp(15px,3.6vw,19px);color:var(--muted);margin:0 0 22px}
    .sticky{position:fixed;left:0;right:0;bottom:0;z-index:20;padding:10px 12px calc(10px + var(--safe-bottom));background:linear-gradient(180deg,transparent,rgba(8,6,17,.9) 28%,rgba(8,6,17,.98));display:flex;justify-content:center;pointer-events:none}
    .sticky .download{min-height:56px;width:min(520px,100%);pointer-events:auto}
    .lang{position:absolute;top:max(16px,env(safe-area-inset-top));right:16px;z-index:5;border:1px solid rgba(255,255,255,.2);border-radius:999px;background:rgba(8,6,17,.36);color:white;padding:9px 12px;backdrop-filter:blur(12px);font-size:13px;font-weight:700;min-width:52px;text-align:center}
    .reveal{opacity:0;transform:translateY(28px);transition:.7s ease}.reveal.in{opacity:1;transform:none}
    @keyframes rise{from{opacity:0;transform:translateY(24px)}to{opacity:1;transform:none}}@keyframes shine{0%,55%{left:-35%}75%,100%{left:130%}}@keyframes marquee-left{from{transform:translateX(0)}to{transform:translateX(-50%)}}@keyframes marquee-right{from{transform:translateX(-50%)}to{transform:translateX(0)}}
    @media(max-width:760px){.gallery-stack{gap:4px}.gallery{gap:10px}.features{grid-template-columns:1fr}.feature{display:grid;grid-template-columns:52px 1fr;column-gap:14px}.feature .icon{grid-row:1/3}.cta{margin-inline:12px}.hero{align-items:end}}
    @media(prefers-reduced-motion:reduce){
      html{scroll-behavior:auto}
      .reveal{opacity:1;transform:none;transition:none}
      .download::after,.hero-content{animation:none}
    }
  
    /* V3: video + two-way scrolling photos only */
    main{padding:clamp(18px,4vw,42px) 0 calc(104px + var(--safe-bottom))}
    main .section{width:100%;padding:0}
    .gallery-stack{gap:clamp(4px,1vw,12px)}
    .gallery-wrap{width:100%}
    .gallery{padding:6px 0}
    .card{width:clamp(170px,26vw,300px);height:clamp(270px,43vw,450px);border-radius:clamp(18px,2.2vw,28px)}
    @media(max-width:760px){main{padding-top:10px}.card{width:44vw;height:68vw}}

    /* V4: feature section at the end */
    .final-features{width:min(1180px,100%);padding:clamp(76px,10vw,128px) 18px clamp(120px,14vw,170px);}
    .final-features .section-head{margin-bottom:clamp(30px,5vw,54px)}
    .final-features .feature{transition:transform .28s ease,border-color .28s ease,background .28s ease,box-shadow .28s ease}
    .final-features .feature:hover{transform:translateY(-7px);border-color:rgba(255,255,255,.24);background:linear-gradient(145deg,rgba(255,255,255,.14),rgba(255,255,255,.06));box-shadow:0 22px 58px rgba(0,0,0,.28)}
    @media(max-width:760px){.final-features{padding-inline:14px;padding-top:72px}.final-features .feature{grid-template-columns:52px minmax(0,1fr)}}