:root{--bg:#EEF5FB;--deep:#E3EEF7;--card:#FFFFFF;--sub:#D7E8F4;--ink:#10263A;--text:#243848;--muted:#5A7388;--soft:#7E93A6;--brand:#3B9FE0;--bright:#62B7EE;--steel:#1E6FB8;--ice:#A9D6F2;--mint:#2FA8A0;--border:rgba(30,111,184,.16);--strong-border:rgba(59,159,224,.38);--shadow:0 16px 40px rgba(16,38,58,.08)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.75 system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei",sans-serif;overflow-x:hidden}a{color:inherit;text-decoration:none}img{max-width:100%;display:block}button,input{font:inherit}.shell{width:min(1220px,calc(100% - 32px));margin:0 auto}.site-header{position:fixed;inset:0 0 auto;z-index:50}.framebar{height:22px;background:var(--steel);color:#fff;font-size:12px}.framebar-inner{height:22px;display:flex;align-items:center;justify-content:space-between}.plain-button{border:0;background:transparent;color:#fff;padding:0 8px;min-height:22px;cursor:pointer}.viewportbar{height:70px;background:rgba(255,255,255,.97);border-bottom:1px solid var(--border);backdrop-filter:blur(10px)}.viewportbar-inner{height:70px;display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:16px}.brand{justify-self:start;display:flex;align-items:center;min-height:44px}.brand-logo,.toolbox-logo,.footer-logo{height:34px;width:auto;object-fit:contain}.brand-text{font-weight:800;color:var(--ink);font-size:20px;letter-spacing:.03em}.toolbox-open,.app-link,.btn{min-height:44px;border-radius:10px;padding:9px 16px;display:inline-flex;align-items:center;justify-content:center;font-weight:700}.toolbox-open{border:1px solid var(--strong-border);background:#fff;color:var(--steel);cursor:pointer}.app-link{justify-self:end;background:linear-gradient(135deg,#62B7EE 0%,#3B9FE0 48%,#1E6FB8 100%);color:#fff}.tabrail{height:44px;background:var(--ice);border-bottom:1px solid rgba(30,111,184,.25)}.tabrail-inner{height:44px;display:flex;align-items:center;gap:8px;overflow:hidden}.tabrail a{padding:5px 10px;border-radius:8px;color:var(--ink);white-space:nowrap;font-size:14px}.tabrail a.active{background:var(--brand);color:#fff}.site-main{padding-top:136px}.section{padding:46px 0}.section.alt{background:var(--deep)}.section.white{background:#fff}.eyebrow{display:inline-block;color:var(--steel);font-size:13px;font-weight:800;letter-spacing:.12em;margin-bottom:8px}.page-title,.hero h1{font-size:clamp(28px,4vw,32px);line-height:1.25;margin:0;color:var(--ink)}h2{color:var(--ink);line-height:1.3}h3{color:var(--ink);line-height:1.4}.lead{font-size:18px;color:var(--muted);max-width:860px}.hero{padding:34px 0 44px}.hero-media,.image-slot{background:linear-gradient(145deg,#e8f4fc,#d7e8f4);border:1px solid var(--border);border-radius:16px;display:flex;align-items:center;justify-content:center;overflow:hidden}.hero-media{max-height:300px;min-height:180px;margin-bottom:24px}.hero-media img{width:100%;max-height:300px;object-fit:contain;object-position:center}.placeholder{min-height:180px;width:100%;display:grid;place-items:center;color:var(--steel);font-weight:800;font-size:24px}.hero-copy{max-width:880px}.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:22px}.btn.primary{background:linear-gradient(135deg,#62B7EE 0%,#3B9FE0 48%,#1E6FB8 100%);color:#fff}.btn.secondary{background:#fff;color:var(--steel);border:1px solid var(--steel)}.tag-grid,.card-grid,.topic-grid,.mini-grid{display:grid;gap:16px}.tag-grid{grid-template-columns:repeat(3,1fr)}.tag-card,.card,.paper,.stat-card{background:#fff;border:1px solid var(--border);border-radius:14px;padding:20px;box-shadow:var(--shadow)}.tag-card:nth-child(odd) .chip{background:var(--bright)}.tag-card:nth-child(even) .chip{background:var(--mint)}.chip{display:inline-block;color:#fff;padding:3px 8px;border-radius:6px;font-size:12px;font-weight:800;margin-bottom:10px}.tag-card p,.card p{margin:8px 0;color:var(--muted)}.inline-link{color:var(--steel);font-weight:800}.feature{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(280px,.9fr);gap:28px;align-items:center}.feature.reverse{grid-template-columns:minmax(280px,.9fr) minmax(0,1.1fr)}.feature.reverse .feature-media{order:-1}.feature-media{background:#fff;border:1px solid var(--border);border-radius:16px;padding:14px}.feature-media img{width:100%;max-height:240px;object-fit:contain}.number-list{display:grid;gap:10px;margin-top:18px}.number-item{display:grid;grid-template-columns:44px 1fr;gap:12px;align-items:start;padding:12px 0;border-top:1px solid var(--border)}.number-item b,.big-no{color:var(--steel);font-size:22px}.card-grid{grid-template-columns:repeat(3,1fr)}.image-card .image-slot{height:210px;margin-bottom:14px}.image-slot img{width:100%;height:100%;object-fit:contain;object-position:center}.topic-grid{grid-template-columns:repeat(3,1fr)}.topic{min-height:150px;border-radius:14px;padding:20px;background:var(--sub);border:1px solid var(--border)}.topic:nth-child(2n){background:#e7f6f4}.shelf{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}.shelf-item{background:#fff;border-left:4px solid var(--brand);border-radius:10px;padding:16px;border-top:1px solid var(--border);border-right:1px solid var(--border);border-bottom:1px solid var(--border)}.timeline{position:relative;margin:20px 0 0 18px;padding-left:28px;border-left:2px solid var(--ice)}.timeline-item{position:relative;padding:0 0 26px}.timeline-item:before{content:"";position:absolute;left:-36px;top:8px;width:14px;height:14px;border-radius:50%;background:var(--brand);box-shadow:0 0 0 5px var(--deep)}.status{display:inline-block;padding:2px 8px;border-radius:6px;background:var(--steel);color:#fff;font-size:12px;font-weight:800}.app-showcase{display:grid;grid-template-columns:minmax(220px,360px) 1fr;gap:34px;align-items:center}.app-shot{background:#fff;border:1px solid var(--border);border-radius:18px;padding:18px;display:flex;justify-content:center}.app-shot img{max-height:420px;object-fit:contain}.app-icon-row{display:flex;gap:14px;align-items:center}.app-icon{width:64px;height:64px;object-fit:contain;border-radius:14px}.content-wrap{width:min(900px,calc(100% - 32px));margin:0 auto}.page-hero{padding:42px 0 26px}.page-hero .wide-media{margin-top:22px;background:#fff;border:1px solid var(--border);border-radius:16px;padding:14px}.page-hero .wide-media img{max-height:280px;width:100%;object-fit:contain}.prose{background:#fff;border:1px solid var(--border);border-radius:16px;padding:28px;box-shadow:var(--shadow);margin-bottom:20px}.prose p{margin:0 0 16px}.prose h2{margin-top:28px}.prose h2:first-child{margin-top:0}.index-list{display:grid;gap:14px}.index-item{display:grid;grid-template-columns:70px 1fr;background:#fff;border:1px solid var(--border);border-radius:14px;padding:18px}.index-item .big-no{font-size:28px;font-weight:800}.stripe-list{display:grid;gap:12px}.stripe{display:grid;grid-template-columns:120px 1fr;gap:18px;padding:18px;border-radius:12px;background:#fff;border:1px solid var(--border)}.faq{display:grid;gap:14px}.faq details{background:#fff;border:1px solid var(--border);border-radius:12px;padding:16px 18px}.faq summary{cursor:pointer;color:var(--ink);font-weight:800}.faq p{margin:12px 0 0}.notice{background:#e7f6f4;border-left:4px solid var(--mint);padding:16px;border-radius:10px;color:var(--text)}.site-footer{background:var(--ink);color:#C7D8E6;padding:44px 0 24px}.footer-grid{display:grid;grid-template-columns:2fr repeat(4,1fr);gap:28px}.footer-brand p{max-width:360px}.footer-brand-link{display:inline-flex;align-items:center}.footer-en{font-weight:800;letter-spacing:.12em;margin-top:8px}.footer-col h2{font-size:15px;color:#fff;margin-top:0}.footer-col{display:flex;flex-direction:column;gap:8px}.footer-col a:hover,.footer-col a:focus-visible{color:#fff}.footer-bottom{border-top:1px solid rgba(255,255,255,.12);padding-top:18px;margin-top:28px;font-size:13px}.overlay{position:fixed;inset:0;background:rgba(16,38,58,.46);z-index:70;opacity:0;visibility:hidden;pointer-events:none;transition:.2s}.overlay.open{opacity:1;visibility:visible;pointer-events:auto}.toolbox{position:fixed;top:0;right:0;bottom:0;width:min(420px,86vw);background:#fff;z-index:80;transform:translateX(105%);visibility:hidden;pointer-events:none;transition:transform .24s ease,visibility .24s;box-shadow:-20px 0 50px rgba(16,38,58,.16);display:flex;flex-direction:column}.toolbox.open{transform:translateX(0);visibility:visible;pointer-events:auto}.toolbox-head{height:74px;display:flex;align-items:center;justify-content:space-between;padding:0 20px;border-bottom:1px solid var(--border)}.toolbox-brand{display:flex;align-items:center;gap:10px;font-weight:800;color:var(--ink)}.toolbox-close,.search-close{min-height:44px;border:1px solid var(--border);background:#fff;color:var(--steel);border-radius:10px;padding:8px 12px;cursor:pointer}.toolbox-body{padding:18px 20px 32px;overflow:auto}.toolbox-body section+section{margin-top:24px}.toolbox-body h2{font-size:14px;margin:0 0 8px;color:var(--steel)}.toolbox-body a{display:block;padding:10px 0;border-bottom:1px solid var(--border)}.toolbox-body strong{display:block;color:var(--ink)}.toolbox-body span{display:block;color:var(--muted);font-size:13px}.search-panel{position:fixed;left:0;right:0;top:92px;z-index:80;visibility:hidden;pointer-events:none;opacity:0;transition:.2s}.search-panel.open{visibility:visible;pointer-events:auto;opacity:1}.search-card{width:min(820px,calc(100% - 32px));margin:0 auto;background:#fff;border:1px solid var(--border);border-radius:0 0 16px 16px;padding:22px;box-shadow:var(--shadow)}.search-top{display:flex;justify-content:space-between;align-items:center;color:var(--ink)}.search-field{display:block;margin-top:14px;color:var(--muted);font-size:13px}.search-field input{display:block;width:100%;min-height:48px;margin-top:8px;border:1px solid var(--strong-border);border-radius:10px;padding:0 14px;color:var(--ink);background:#fff}.search-links{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}.search-links a{min-height:40px;display:inline-flex;align-items:center;padding:6px 12px;border-radius:9px;background:var(--deep);color:var(--steel);font-weight:700}.search-note{font-size:13px;color:var(--muted);margin-bottom:0}.mobile-bottom{display:none}.no-scroll{overflow:hidden}.toolbox-open:hover,.toolbox-open:focus-visible,.btn.secondary:hover,.btn.secondary:focus-visible,.search-links a:hover,.search-links a:focus-visible{border-color:var(--brand);outline:3px solid rgba(59,159,224,.16)}.app-link:hover,.app-link:focus-visible,.btn.primary:hover,.btn.primary:focus-visible{outline:3px solid rgba(59,159,224,.22);filter:brightness(1.03)}
@media(max-width:900px){.tag-grid,.card-grid,.topic-grid{grid-template-columns:repeat(2,1fr)}.feature,.feature.reverse,.app-showcase{grid-template-columns:1fr}.feature.reverse .feature-media{order:0}.footer-grid{grid-template-columns:repeat(2,1fr)}.footer-brand{grid-column:1/-1}}
@media(max-width:680px){body{padding-bottom:calc(58px + env(safe-area-inset-bottom))}.site-main{padding-top:92px}.tabrail{display:none}.viewportbar-inner{grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);gap:8px}.brand-logo{height:30px}.brand-text{font-size:17px}.toolbox-open,.app-link{padding:7px 10px;min-width:0;font-size:14px}.tag-grid,.card-grid,.topic-grid,.shelf{grid-template-columns:1fr}.section{padding:34px 0}.hero{padding-top:26px}.hero-media{min-height:150px}.image-card .image-slot{height:190px}.prose{padding:20px}.index-item{grid-template-columns:52px 1fr;padding:16px}.stripe{grid-template-columns:1fr;gap:6px}.footer-grid{grid-template-columns:1fr 1fr;gap:22px}.search-panel{top:0;bottom:0;background:var(--ice);padding:16px;overflow:auto}.search-card{width:100%;margin:0;background:#fff;border-radius:16px}.mobile-bottom{position:fixed;left:0;right:0;bottom:0;z-index:60;height:calc(50px + env(safe-area-inset-bottom));padding-bottom:env(safe-area-inset-bottom);display:grid;grid-template-columns:repeat(5,1fr);background:#fff;border-top:1px solid var(--border);box-shadow:0 -8px 28px rgba(16,38,58,.08)}.mobile-bottom a{display:flex;align-items:center;justify-content:center;font-size:13px;color:var(--muted)}.mobile-bottom a.active{background:var(--brand);color:#fff}.toolbox{z-index:80}.overlay{z-index:70}}