:root{--ink:#15171b;--blue:#5676a8;--red:#d92530;--paper:#fff;--soft:#f3f5f8;--line:#dce1e8;--muted:#66707c;--shell:1380px}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Arial,"Microsoft YaHei","PingFang SC",sans-serif;color:var(--ink);line-height:1.76;background:#fff}img{display:block;max-width:100%}a{text-decoration:none;color:inherit}
.header-shell,.hero,.preview-section,.steps-section,.after-shell,.faq-section,.footer-shell{width:min(calc(100% - 56px),var(--shell));margin:auto}
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.97);border-bottom:1px solid var(--line)}.header-shell{height:74px;display:grid;grid-template-columns:250px 1fr 140px;align-items:center;gap:25px}.brand{display:flex;align-items:center;gap:10px;font-size:9px;font-weight:900;letter-spacing:.13em}.brand img,footer img{height:28px;width:auto;background:#15171b;padding:5px 9px}.site-nav{display:flex;justify-content:center;gap:25px;font-size:12px;font-weight:800;color:#66707c}.top-btn{background:var(--red);color:#fff;padding:10px 14px;font-size:12px;font-weight:900}.menu-button{display:none}
.kicker{color:var(--blue);font-size:10px;font-weight:900;letter-spacing:.15em;margin:0 0 12px}.hero{display:grid;grid-template-columns:.82fr 1.18fr;gap:70px;align-items:center;min-height:620px;padding:70px 0}.hero h1{margin:0;font-size:clamp(52px,6.8vw,92px);line-height:.96;letter-spacing:-.067em}.lead{font-size:18px;color:var(--muted);margin-top:26px}.hero-actions{display:flex;gap:20px;align-items:center;margin-top:30px}.primary{display:inline-flex;background:var(--red);color:#fff;padding:15px 20px;font-weight:900}.hero-device{margin:0}.hero-device img{width:100%;max-height:500px;object-fit:contain;background:var(--soft)}figcaption{margin-top:8px;color:var(--muted);font-size:10px}
.quick-download{display:grid;grid-template-columns:repeat(3,1fr) 280px;width:min(calc(100% - 56px),var(--shell));margin:auto;border-top:2px solid var(--ink);border-left:1px solid var(--line)}.quick-download>div{padding:18px;border-right:1px solid var(--line);border-bottom:1px solid var(--line)}.quick-download span{display:block;font-size:8px;color:var(--blue);font-weight:900}.quick-download strong{font-size:12px}.quick-download>a{display:grid;place-items:center;background:var(--ink);color:#fff;font-size:12px;font-weight:900}
.preview-section,.steps-section,.faq-section{padding:95px 0}.section-head{max-width:900px}.section-head h2,.after-shell h2{font-size:clamp(34px,4vw,52px);line-height:1.15;letter-spacing:-.045em;margin:0}.section-head>p:not(.kicker),.after-shell p:not(.kicker){color:var(--muted)}
.preview-grid{display:grid;grid-template-columns:1.25fr .75fr;grid-template-rows:1fr 1fr;gap:20px;margin-top:38px}.preview-grid figure{margin:0;border-top:3px solid var(--blue)}.preview-grid .large{grid-row:1/3}.preview-grid img{width:100%;height:100%;object-fit:contain;background:var(--soft)}.preview-grid figcaption{display:grid}.preview-grid figcaption span{color:var(--muted)}
.steps-section{background:var(--soft);width:100%;padding-left:max(28px,calc((100% - var(--shell))/2));padding-right:max(28px,calc((100% - var(--shell))/2))}.steps{list-style:none;padding:0;margin:35px 0 0;max-width:1000px;border-top:2px solid var(--ink)}.steps li{display:grid;grid-template-columns:110px 1fr;gap:22px;padding:20px 0;border-bottom:1px solid var(--line)}.steps span{color:var(--blue);font-size:9px;font-weight:900}.steps h3{margin:-3px 0 5px}.steps p{margin:0;color:var(--muted)}
.after-section{background:#15171b;color:#fff}.after-shell{display:grid;grid-template-columns:1.15fr .85fr;gap:65px;align-items:center;padding:95px 0}.after-shell figure{margin:0}.after-shell img{width:100%;max-height:460px;object-fit:contain;background:#0b0c0e}.after-shell p:not(.kicker){color:#aab0b8}
.faq-list{margin-top:30px;border-top:2px solid var(--ink)}details{border-bottom:1px solid var(--line)}summary{list-style:none;position:relative;padding:20px 45px 20px 0;font-weight:850;cursor:pointer}summary span{position:absolute;right:0}.faq-list p{margin:-3px 0 20px;color:var(--muted)}
footer{background:#0f1012;color:#777;padding:40px 0}.footer-shell p{font-size:10px;max-width:850px}.mobile-bar{display:none}
@media(max-width:800px){.header-shell{grid-template-columns:1fr auto}.site-nav,.top-btn{display:none}.menu-button{display:block}.site-nav.is-open{display:grid;position:absolute;top:70px;left:18px;right:18px;background:#fff;padding:12px;border:1px solid var(--line)}.hero,.after-shell{grid-template-columns:1fr}.quick-download{grid-template-columns:1fr 1fr}.preview-grid{grid-template-columns:1fr;grid-template-rows:auto}.preview-grid .large{grid-row:auto}}
@media(max-width:600px){body{padding-bottom:60px}.header-shell,.hero,.preview-section,.steps-section,.after-shell,.faq-section,.footer-shell,.quick-download{width:min(calc(100% - 28px),var(--shell))}.brand span{display:none}.hero{min-height:0;padding:52px 0}.hero h1{font-size:clamp(45px,13vw,62px)}.lead{font-size:16px}.hero-actions{display:grid}.quick-download{grid-template-columns:1fr}.steps-section{padding:70px 14px}.steps li{grid-template-columns:1fr;gap:5px}.after-shell{padding:70px 0}.mobile-bar{position:fixed;left:0;right:0;bottom:0;z-index:90;height:60px;background:#15171b;color:#fff;display:flex;align-items:center;justify-content:space-between;padding:8px 14px}.mobile-bar a{background:var(--red);padding:9px 15px;font-weight:900}}