:root{--bg:#f5fbff;--paper:#fff;--ice:#eaf7fc;--soft:#dff5fb;--cyan:#25c8d1;--sky:#25b6e8;--blue:#1787db;--deep:#174b78;--heading:#173b60;--text:#2d4359;--muted:#687f93;--stroke:#dcebf3;--footer:#123653;--max:1160px;--radius:18px;--shadow:0 14px 38px rgba(16,75,113,.07)}
*,*::before,*::after{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:92px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif;-webkit-font-smoothing:antialiased}body.nav-open{overflow:hidden}a{color:inherit;text-decoration:none}a:hover{color:var(--blue)}img{max-width:100%}button{font:inherit;cursor:pointer}h1,h2,h3,p{margin-top:0}h1,h2,h3{line-height:1.4;color:var(--heading)}h1{font-size:clamp(27px,3.7vw,40px);letter-spacing:-.025em}h2{font-size:clamp(20px,2.35vw,26px)}h3{font-size:19px}p{margin-bottom:1em}.container{width:min(var(--max),calc(100% - 48px));margin-inline:auto}.skip-link{position:absolute;z-index:80;top:-60px;left:16px;background:#fff;padding:8px 16px}.skip-link:focus{top:6px}.site-header{background:#fff;border-bottom:1px solid var(--stroke);position:sticky;top:0;z-index:30}.header-inner{display:flex;gap:24px;align-items:center;min-height:72px}.brand{display:inline-flex;align-items:center;flex-shrink:0;color:var(--heading);font-weight:800;line-height:1.1;white-space:nowrap}.brand-logo{display:block;height:37px;width:auto;max-width:190px;object-fit:contain}.brand-fallback{display:inline-flex;align-items:center;gap:9px;font-size:19px}.brand-fallback small{display:block;font-size:9px;letter-spacing:.2em;color:var(--blue);margin-top:4px}.brand-ball{display:grid;place-items:center;width:35px;height:35px;border-radius:50%;background:linear-gradient(135deg,var(--cyan),var(--blue));color:white}.desktop-nav{display:flex;align-items:center;gap:clamp(12px,1.4vw,24px);margin:auto}.desktop-nav a{font-size:14px;font-weight:700;white-space:nowrap;position:relative;padding:24px 0}.desktop-nav a[aria-current=page]{color:var(--blue)}.desktop-nav a[aria-current=page]::after{content:"";height:3px;background:var(--cyan);position:absolute;bottom:0;left:0;right:0;border-radius:4px}.main-btn{display:inline-flex;align-items:center;justify-content:center;min-width:82px;height:42px;padding:0 20px;border-radius:999px;background:linear-gradient(110deg,#25c8d1,#25b6e8,#1787db);color:#fff;font-weight:700;white-space:nowrap;box-shadow:0 8px 20px rgba(23,135,219,.18)}.main-btn:hover{color:white;filter:brightness(.97);transform:translateY(-1px)}.menu-toggle{display:none;border:0;background:none;padding:8px;flex-direction:column;gap:5px}.menu-toggle span{width:23px;height:2px;background:var(--heading);border-radius:10px}.drawer-overlay{position:fixed;inset:0;background:rgba(10,35,58,.5);z-index:40;visibility:hidden;opacity:0;pointer-events:none;transition:opacity .2s,visibility .2s}.drawer{position:fixed;top:0;bottom:0;left:0;width:min(86vw,340px);background:#fff;z-index:41;transform:translateX(-105%);visibility:hidden;transition:transform .24s,visibility .24s;overflow-y:auto;padding:18px 22px}.nav-open .drawer-overlay{visibility:visible;opacity:1;pointer-events:auto}.nav-open .drawer{visibility:visible;transform:translateX(0)}.drawer-head{display:flex;justify-content:space-between;align-items:center;padding-bottom:22px;border-bottom:1px solid var(--stroke)}.drawer-close{font-size:30px;border:0;background:none;color:var(--heading)}.drawer-label{display:block;margin-top:20px;color:var(--blue);font-weight:800;font-size:13px;letter-spacing:.04em}.drawer nav a{display:block;padding:9px 2px;border-bottom:1px solid #f0f6fa;font-size:15px}.eyebrow{font-weight:800;font-size:12px;letter-spacing:.17em;color:var(--blue);text-transform:uppercase;margin-bottom:14px}.lead{font-size:17px;line-height:1.85;color:#516d82;max-width:800px}.section{padding-block:36px}.section-head{display:flex;align-items:end;justify-content:space-between;gap:20px;margin-bottom:24px}.section-head p{max-width:660px;margin-bottom:0;color:var(--muted)}.section-link{color:var(--blue);font-weight:700;white-space:nowrap}.hero{padding-block:46px 24px}.hero-grid{display:grid;grid-template-columns:1.08fr .92fr;gap:35px;align-items:center}.hero h1{max-width:630px}.hero-copy p{font-size:17px;max-width:630px}.hero-actions{display:flex;gap:14px;flex-wrap:wrap;margin-top:25px}.quiet-btn{display:inline-flex;align-items:center;justify-content:center;height:42px;padding:0 20px;border:1px solid #bbdfed;border-radius:999px;font-weight:700;color:var(--deep)}.hero-notes{display:flex;flex-wrap:wrap;gap:10px;margin-top:22px;color:#57758a;font-size:13px}.hero-notes span{background:var(--ice);border-radius:30px;padding:4px 11px}.media{width:100%;display:flex;align-items:center;justify-content:center;overflow:hidden;border-radius:16px;background:linear-gradient(150deg,#dff5fb,#eaf7fc 55%,#c9edfa);position:relative;isolation:isolate}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center;position:relative;z-index:2}.media--hero{min-height:275px;max-height:340px}.media--landscape{min-height:175px;max-height:255px}.media--wide{min-height:180px;max-height:260px}.media--portrait{min-height:240px;max-height:350px}.media--empty{background:radial-gradient(circle at 72% 24%,#c4f0fa 0,transparent 45%),linear-gradient(125deg,#dff5fb,#eaf7fc 62%,#c8edfb)}.media-orbit{position:absolute;width:64%;aspect-ratio:1;border:1px solid rgba(37,182,232,.24);border-radius:50%;left:20%;top:-45%;background:radial-gradient(circle,rgba(37,200,209,.09),transparent 66%)}.media-orbit--two{width:42%;left:45%;top:40%;border:22px solid rgba(37,182,232,.08)}.panel,.topic-card,.feature-card{background:#fff;border:1px solid var(--stroke);border-radius:var(--radius);box-shadow:var(--shadow)}.panel{padding:clamp(20px,3vw,34px)}.topic-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.topic-card{display:flex;flex-direction:column;padding:24px;min-height:178px;transition:transform .2s,border .2s}.topic-card:hover{transform:translateY(-3px);border-color:#a9ddec}.topic-card .index{font-size:12px;color:var(--blue);font-weight:800;letter-spacing:.1em}.topic-card h3{margin:14px 0 6px}.topic-card p{font-size:14px;color:var(--muted);line-height:1.65}.topic-card .arrow{margin-top:auto;color:var(--blue);font-weight:700}.split{display:grid;grid-template-columns:1fr 1fr;gap:28px;align-items:center}.split--wide{grid-template-columns:1.16fr .84fr}.story-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.story-list article{padding:24px;background:#fff;border:1px solid var(--stroke);border-radius:16px}.story-list h3{margin-bottom:8px}.story-list p{color:var(--muted);font-size:15px}.story-list a{color:var(--blue);font-weight:700}.tag{display:inline-block;padding:3px 10px;border-radius:999px;background:#dff5fb;color:#116b9d;font-size:12px;font-weight:800}.page-intro{padding-block:52px 24px}.page-intro h1{font-size:clamp(26px,3vw,34px);margin-bottom:14px}.page-intro .lead{max-width:860px}.article-shell{padding-bottom:64px}.article-body{max-width:820px;margin-inline:auto}.article-body p,.article-body li{line-height:1.85}.article-body h2{margin-top:35px}.article-body h3{margin-top:23px}.article-body ul,.article-body ol{padding-left:1.4em}.article-body li{margin-bottom:8px}.article-body .media{margin:25px 0}.article-body .info-box{background:var(--ice);border-left:4px solid var(--cyan);padding:18px 23px;margin:25px 0;border-radius:0 12px 12px 0}.article-body .info-box p:last-child{margin-bottom:0}.content-layout{display:grid;grid-template-columns:minmax(0,1fr) 270px;gap:28px;align-items:start}.sticky-side{position:sticky;top:102px}.side-panel{padding:22px;border-radius:16px;background:#fff;border:1px solid var(--stroke)}.side-panel h2{font-size:18px}.side-panel a{display:block;padding:7px 0;border-bottom:1px solid var(--stroke);color:var(--deep);font-size:14px}.side-panel a:last-child{border-bottom:0}.compare{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin:22px 0}.compare>div{background:var(--ice);border-radius:15px;padding:23px}.compare h3{color:var(--deep)}.data-table{border-collapse:collapse;width:100%;margin:24px 0;background:white;font-size:15px}.data-table th,.data-table td{padding:12px 14px;border:1px solid var(--stroke);text-align:left;vertical-align:top}.data-table th{background:var(--ice);color:var(--heading);font-weight:800}.table-scroll{overflow-x:auto}.steps{counter-reset:step;list-style:none!important;padding:0!important}.steps li{position:relative;padding:15px 18px 15px 58px;background:white;border:1px solid var(--stroke);border-radius:13px;margin-bottom:12px}.steps li::before{counter-increment:step;content:counter(step);position:absolute;left:16px;top:16px;display:grid;place-items:center;width:28px;height:28px;border-radius:50%;background:var(--blue);color:white;font-weight:800}.quote{font-size:20px;color:var(--heading);border-left:3px solid var(--cyan);padding:12px 20px;background:var(--ice);border-radius:0 15px 15px 0}.related{margin-top:42px}.related h2{margin-bottom:18px}.related-links{display:flex;flex-wrap:wrap;gap:10px}.related-links a{display:inline-flex;align-items:center;gap:16px;border:1px solid #cbe5ef;padding:8px 14px;border-radius:999px;color:var(--deep);font-weight:700;font-size:14px}.related-links span{color:var(--blue)}.feature-strip{padding:22px;background:linear-gradient(110deg,#e1f6fa,#f2fbff);border:1px solid #c9e9f0;border-radius:16px}.feature-strip h2{margin-bottom:8px}.feature-strip p{margin-bottom:0}.bullet-columns{columns:2;column-gap:26px}.bullet-columns li{break-inside:avoid}.visual-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}.visual-grid figure{margin:0;padding:14px;background:#fff;border:1px solid var(--stroke);border-radius:17px}.visual-grid .media{min-height:160px}.visual-grid figcaption{padding:12px 5px 4px;font-size:14px;color:#526d83}.faq details{padding:17px 0;border-bottom:1px solid var(--stroke)}.faq summary{cursor:pointer;color:var(--heading);font-weight:800}.faq details p{margin:12px 0 0}.site-footer{background:var(--footer);color:#eaf7ff;margin-top:35px}.footer-grid{display:grid;grid-template-columns:1.1fr 1fr .95fr;gap:55px;padding:50px 0}.footer-grid h2{color:#fff;font-size:17px}.footer-grid p{font-size:14px;color:#cce4ee}.footer-grid nav{display:grid;grid-template-columns:1fr 1fr;gap:8px 12px}.footer-grid nav a{font-size:14px;color:#d7eef6}.footer-grid a:hover{color:white}.brand--footer .brand-fallback,.brand--footer .brand-fallback small{color:white}.footer-link{color:#90edfa;font-weight:700;font-size:14px}.footer-bottom{padding:15px 0 22px;border-top:1px solid rgba(255,255,255,.14);display:flex;justify-content:space-between;gap:20px;font-size:12px;color:#b3d1df}.bottom-nav{display:none}.back-top{position:fixed;right:22px;bottom:24px;z-index:20;border:0;border-radius:50%;width:42px;height:42px;background:var(--deep);color:#fff;box-shadow:0 5px 17px #0d436144;opacity:0;visibility:hidden;transition:.2s}.back-top.show{opacity:1;visibility:visible}
@media(max-width:1120px){.desktop-nav{gap:12px}.desktop-nav a{font-size:13px}.header-inner{gap:15px}.brand-logo{max-width:155px}}
@media(max-width:980px){.desktop-nav{display:none}.menu-toggle{display:flex}.header-inner{justify-content:space-between;min-height:60px}.brand{margin-inline:auto}.header-cta{height:40px;padding:0 14px}.brand-logo{height:30px;max-width:150px}.hero-grid{gap:20px}.content-layout{grid-template-columns:1fr}.sticky-side{position:static}.side-panel{display:none}.footer-grid{gap:30px}}
@media(max-width:650px){body{font-size:15px}.container{width:calc(100% - 32px)}.header-inner{gap:6px}.brand-logo{height:28px;max-width:128px}.brand-fallback{font-size:15px;gap:5px}.brand-fallback small{font-size:7px}.brand-ball{width:27px;height:27px}.menu-toggle{padding:6px}.menu-toggle span{width:21px}.header-cta{font-size:12px;min-width:74px;height:38px;padding:0 12px}.hero{padding:26px 0 5px}.hero-grid,.split,.split--wide,.compare{grid-template-columns:1fr}.hero-grid .media{order:-1}.hero .media--hero{min-height:170px;max-height:230px}.hero h1{font-size:29px}.hero-copy p,.lead{font-size:15px}.hero-actions{margin-top:16px}.section{padding-block:27px}.section-head{align-items:start;flex-direction:column;gap:8px}.topic-grid{grid-template-columns:1fr 1fr;gap:10px}.topic-card{min-height:170px;padding:16px}.topic-card h3{font-size:17px}.topic-card p{font-size:13px}.story-list,.visual-grid{grid-template-columns:1fr}.page-intro{padding:30px 0 15px}.page-intro h1{font-size:26px}.article-shell{padding-bottom:30px}.article-body h2{margin-top:28px}.media--landscape,.media--wide{min-height:145px;max-height:195px}.media--portrait{min-height:180px;max-height:290px}.panel{padding:20px}.bullet-columns{columns:1}.data-table{font-size:13px}.data-table th,.data-table td{padding:9px}.footer-grid{grid-template-columns:1fr;gap:20px;padding:35px 0}.footer-bottom{flex-direction:column;gap:4px;padding-bottom:82px}.bottom-nav{display:grid;grid-template-columns:repeat(4,1fr);position:fixed;bottom:0;left:0;right:0;z-index:29;background:#fff;border-top:1px solid var(--stroke);box-shadow:0 -6px 22px #24455c0d;padding-bottom:env(safe-area-inset-bottom)}.bottom-nav a{display:grid;place-items:center;font-size:13px;font-weight:700;min-height:52px;color:var(--deep)}.bottom-nav a[aria-current=page]{color:var(--blue);background:#f2fbff}.back-top{bottom:70px;right:14px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition-duration:.01ms!important;animation-duration:.01ms!important}}