:root{--bg:#F5FBFF;--surface:#fff;--muted:#EAF7FC;--pale:#DFF5FB;--cyan:#25C8D1;--sky:#25B6E8;--blue:#1787DB;--navy:#174B78;--heading:#173B60;--text:#2D4359;--soft:#687F93;--line:#DCEBF3;--footer:#123653;--radius:18px;--shadow:0 12px 32px rgba(21,90,133,.07)}
*{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}body.drawer-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{color:var(--heading);line-height:1.38}h1{font-size:clamp(27px,3vw,40px);letter-spacing:-.025em}h2{font-size:clamp(21px,2vw,26px)}h3{font-size:19px}p{margin-bottom:1.1em}.container{max-width:1160px;margin:auto;padding:0 24px}.site-header{position:sticky;top:0;z-index:30;background:#fff;border-bottom:1px solid var(--line);box-shadow:0 3px 14px rgba(16,72,109,.035)}.header-inner{height:72px;display:flex;align-items:center;gap:20px}.brand{display:inline-flex;flex:0 0 auto;align-items:center;min-width:174px}.brand img{width:auto;max-width:176px;height:38px;object-fit:contain}.brand-symbol{display:grid;place-items:center;width:38px;height:38px;border-radius:12px;background:linear-gradient(130deg,var(--cyan),var(--blue));color:white;font-weight:800;font-size:25px}.brand-word{display:flex;flex-direction:column;line-height:1.2;margin-left:9px;color:var(--heading)}.brand-word strong{font-size:20px}.brand-word small{font-size:9px;letter-spacing:.12em;color:var(--soft);margin-top:3px}.desktop-nav{display:flex;gap:clamp(10px,1.45vw,23px);align-items:center;flex:1;justify-content:center;white-space:nowrap}.desktop-nav a{font-size:14px;font-weight:600;position:relative;padding:23px 0}.desktop-nav a.is-active{color:var(--blue)}.desktop-nav a.is-active:after{content:'';position:absolute;bottom:0;left:0;right:0;height:3px;border-radius:4px;background:var(--cyan)}.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;line-height:1.2}.main-btn:hover{color:#fff;filter:brightness(.96);box-shadow:0 5px 15px rgba(37,182,232,.24)}.header-action{font-size:14px}.menu-toggle{display:none;border:0;background:none;width:42px;height:42px;align-items:center;justify-content:center;flex-direction:column;gap:5px}.menu-toggle span{display:block;width:20px;height:2px;background:var(--heading);border-radius:2px}.skip-link{position:absolute;left:12px;top:-80px;padding:8px 12px;background:#fff;z-index:101}.skip-link:focus{top:5px}.drawer-shade{position:fixed;inset:0;background:rgba(9,32,50,.52);z-index:39;opacity:0;visibility:hidden;pointer-events:none;transition:.2s}.mobile-drawer{position:fixed;top:0;left:0;bottom:0;z-index:40;width:min(86vw,340px);overflow-y:auto;background:#fff;box-shadow:10px 0 28px rgba(0,0,0,.1);transform:translateX(-110%);visibility:hidden;transition:transform .24s,visibility .24s;padding:20px}.drawer-open .drawer-shade{opacity:1;visibility:visible;pointer-events:auto}.drawer-open .mobile-drawer{visibility:visible;transform:translateX(0)}.drawer-top{display:flex;justify-content:space-between;align-items:center;color:var(--heading);font-weight:700;font-size:20px}.drawer-close{border:0;background:var(--muted);border-radius:50%;font-size:28px;width:38px;height:38px;line-height:1}.drawer-group{border-bottom:1px solid var(--line);padding:15px 0}.drawer-group p{font-size:12px;letter-spacing:.06em;color:var(--soft);font-weight:700;margin:0 0 6px}.drawer-group a{display:block;padding:6px 0;font-weight:600}.bottom-nav{display:none}.back-top{position:fixed;right:22px;bottom:23px;width:42px;height:42px;border:0;border-radius:50%;background:var(--blue);color:white;z-index:12;box-shadow:var(--shadow)}.back-top[hidden]{display:none}.eyebrow{display:inline-flex;align-items:center;gap:7px;font-size:12px;font-weight:800;text-transform:uppercase;letter-spacing:.12em;color:#117DAB;margin-bottom:14px}.eyebrow:before{content:'';width:17px;height:3px;border-radius:5px;background:var(--cyan)}.lead{font-size:17px;color:#506A7E;max-width:760px}.hero{padding:60px 0 58px;background:radial-gradient(circle at 87% 15%,#DFF7FD,transparent 42%),linear-gradient(120deg,#F4FCFF,#EAF7FC)}.hero-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:45px;align-items:center}.hero h1{max-width:620px}.hero-description{font-size:17px;max-width:590px;color:#526E83}.hero-actions{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-top:24px}.text-link{color:var(--blue);font-weight:700}.hero-meta{display:flex;gap:20px;flex-wrap:wrap;margin-top:32px;padding-top:17px;border-top:1px solid #cde7f0;color:var(--soft);font-size:13px}.hero-meta b{color:var(--heading)}.media{display:flex;justify-content:center;align-items:center;width:100%;min-width:0;overflow:hidden;background:var(--muted);border-radius:16px}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.media-placeholder{position:relative;flex-direction:column;gap:10px;padding:20px;text-align:center;color:#417A9A;font-size:13px;font-weight:700;background:linear-gradient(145deg,#DEF4F9,#F4FCFF);border:1px solid #C9EAF2}.placeholder-mark{display:block;width:70px;height:70px;border:2px solid #7ECFDE;border-radius:22px;transform:rotate(-12deg);background:radial-gradient(circle at 70% 25%,#81DAE8 0 8px,transparent 9px),linear-gradient(145deg,transparent 52%,#ACE3EA 53% 67%,transparent 68%)}.media-hero{height:310px}.media-card{height:170px}.media-wide{height:240px}.media-portrait{height:310px;max-width:320px;margin:auto}.section{padding:52px 0}.section-alt{background:#EDF8FC}.section-heading{display:flex;align-items:end;justify-content:space-between;gap:16px;margin-bottom:24px}.section-heading h2{margin:0}.section-heading p{margin:9px 0 0;color:var(--soft)}.feature-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.feature-card,.panel,.topic-card,.article-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.feature-card{overflow:hidden}.feature-card-body{padding:20px}.feature-card h3{margin-bottom:8px}.feature-card p{font-size:14px;color:var(--soft)}.feature-card a.inline-arrow,.panel a.inline-arrow{color:var(--blue);font-weight:700;font-size:14px}.split{display:grid;grid-template-columns:1fr 1fr;gap:34px;align-items:center}.panel{padding:27px}.pill-list{display:flex;gap:10px;flex-wrap:wrap}.pill{border:1px solid #BCE5F0;background:#F0FBFD;color:var(--navy);border-radius:50px;padding:6px 14px;font-weight:700;font-size:13px}.topic-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.topic-card{padding:24px}.topic-card h3{margin:0 0 10px}.topic-card p{font-size:14px;color:var(--soft);margin-bottom:0}.section-index{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:13px}.index-item{display:flex;justify-content:space-between;gap:10px;align-items:center;background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px 19px;color:var(--heading);font-weight:700}.index-item span{color:var(--sky)}.index-item:hover{border-color:var(--sky);color:var(--blue)}.page-hero{padding:58px 0 40px;background:linear-gradient(115deg,#EFFBFF,#E5F6FC)}.page-hero h1{max-width:850px}.page-hero .lead{margin:0}.breadcrumb{font-size:13px;color:var(--soft);margin:0 0 15px}.breadcrumb a{color:var(--blue)}.content{padding:44px 0 70px}.article-width{max-width:820px;margin:auto}.article-width>section{margin-bottom:42px}.article-width p{line-height:1.84}.article-width h2{margin:28px 0 14px}.article-width h3{margin:22px 0 9px}.article-width ul,.article-width ol{padding-left:22px}.article-width li{margin-bottom:8px}.note{border-left:4px solid var(--cyan);padding:17px 22px;background:var(--muted);border-radius:0 12px 12px 0;margin:24px 0}.info-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin:24px 0}.info-grid .panel{box-shadow:none}.compare-table{width:100%;border-collapse:collapse;background:white;border:1px solid var(--line);font-size:15px;display:table}.compare-table th,.compare-table td{padding:13px 16px;text-align:left;border:1px solid var(--line);vertical-align:top}.compare-table th{background:#DFF5FB;color:var(--heading)}.table-scroll{overflow-x:auto;margin:24px 0}.number-list{counter-reset:steps;list-style:none!important;padding-left:0!important}.number-list li{counter-increment:steps;position:relative;padding:15px 18px 15px 62px;margin-bottom:12px;background:white;border:1px solid var(--line);border-radius:12px}.number-list li:before{content:counter(steps,decimal-leading-zero);position:absolute;left:16px;top:14px;font-weight:800;color:var(--blue)}.quote{padding:23px 29px;background:var(--muted);border-radius:15px;color:var(--heading);font-size:19px;font-weight:700}.related{margin-top:44px;padding-top:28px;border-top:1px solid var(--line)}.related-links{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}.related-links a{display:flex;justify-content:space-between;align-items:center;gap:8px;border:1px solid var(--line);border-radius:12px;padding:14px;background:white;color:var(--heading);font-size:14px;font-weight:700}.related-links a span{color:var(--blue)}.label-row{display:flex;gap:8px;flex-wrap:wrap;margin:12px 0}.label-row span{background:#E8F7FB;color:#176D91;border-radius:20px;padding:2px 10px;font-size:12px;font-weight:700}.visual-row{display:grid;grid-template-columns:1fr 1fr;align-items:center;gap:32px;margin:32px 0}.visual-row:nth-child(even) .media{order:2}.faq-list details{padding:17px 0;border-bottom:1px solid var(--line)}.faq-list summary{color:var(--heading);font-weight:700;cursor:pointer}.faq-list details p{margin:10px 0 0;font-size:15px}.site-footer{background:var(--footer);color:#EAF7FF;padding:43px 0 0}.footer-grid{display:grid;grid-template-columns:2fr repeat(3,1fr);gap:36px}.footer-grid p{color:#C8E5F2;font-size:13px;max-width:320px}.footer-grid h2{font-size:15px;color:white}.footer-grid>div>a:not(.footer-brand){display:block;color:#D2E9F2;font-size:13px;padding:3px 0}.footer-brand{color:#fff;font-size:23px;font-weight:800}.footer-brand small{display:block;font-size:10px;letter-spacing:.18em;font-weight:500}.footer-bottom{margin-top:36px;border-top:1px solid rgba(255,255,255,.17);padding-top:18px;padding-bottom:18px;display:flex;justify-content:space-between;gap:16px;color:#B3D0DF;font-size:12px}
@media(max-width:1080px){.desktop-nav{gap:11px}.desktop-nav a{font-size:13px}.brand{min-width:145px}.brand img{max-width:145px}}
@media(max-width:980px){.desktop-nav{display:none}.menu-toggle{display:flex}.header-inner{height:60px;justify-content:space-between;gap:10px;position:relative}.brand{min-width:0;position:absolute;left:50%;transform:translateX(-50%);justify-content:center}.brand img{max-width:140px;height:29px}.brand-symbol{height:30px;width:30px;font-size:18px}.brand-word strong{font-size:16px}.brand-word small{font-size:8px}.header-action{height:38px;min-width:76px;padding:0 12px;font-size:12px;margin-left:auto}.bottom-nav{display:flex;position:fixed;bottom:0;left:0;right:0;height:58px;z-index:25;background:#fff;border-top:1px solid var(--line);justify-content:space-around;align-items:center;box-shadow:0 -3px 16px rgba(0,0,0,.05)}.bottom-nav a{font-size:13px;font-weight:700;color:var(--navy);padding:10px 13px}.bottom-nav a.is-active{color:var(--blue)}.site-footer{padding-bottom:58px}.back-top{bottom:75px}.hero{padding:42px 0}.hero-grid{gap:22px}.footer-grid{grid-template-columns:2fr 1fr 1fr}.footer-grid>div:last-child{grid-column:2/4}}
@media(max-width:700px){.container{padding:0 16px}.hero-grid,.split,.visual-row{grid-template-columns:1fr}.hero-grid .media{order:-1}.hero-grid{gap:22px}.hero h1{font-size:29px}.hero-description,.lead{font-size:15px}.hero-meta{gap:9px 16px}.media-hero{height:210px}.media-card{height:145px}.media-wide{height:175px}.media-portrait{height:250px}.section{padding:32px 0}.section-heading{align-items:start}.section-heading h2{font-size:22px}.feature-grid,.section-index{grid-template-columns:1fr 1fr;gap:12px}.feature-card-body{padding:14px}.feature-card h3{font-size:16px}.feature-card p{font-size:13px}.topic-list,.info-grid{grid-template-columns:1fr}.topic-card,.panel{padding:20px}.page-hero{padding:35px 0 30px}.page-hero h1{font-size:27px}.content{padding:26px 0 48px}.article-width h2{font-size:22px}.article-width h3{font-size:18px}.article-width p,.article-width li{font-size:15px}.compare-table{min-width:520px}.related-links{grid-template-columns:1fr}.visual-row:nth-child(even) .media{order:0}.footer-grid{grid-template-columns:1fr 1fr;gap:24px}.footer-grid>div:first-child{grid-column:1/3}.footer-grid>div:last-child{grid-column:auto}.footer-bottom{flex-direction:column;gap:3px}.section-index .index-item{padding:14px 11px;font-size:13px}}
@media(max-width:370px){.brand-word small{display:none}.brand-word strong{font-size:14px}.header-action{font-size:11px;padding:0 10px}.feature-grid{grid-template-columns:1fr}.section-index{grid-template-columns:1fr}.menu-toggle{width:36px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important}}