:root{--bg:#f5fbff;--white:#fff;--soft:#eaf7fc;--soft2:#dff5fb;--cyan:#25c8d1;--sky:#25b6e8;--blue:#1787db;--deep:#174b78;--ink:#173b60;--body:#2d4359;--muted:#687f93;--border:#dcebf3;--footer:#123653;--shadow:0 16px 44px rgba(23,75,120,.07)}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:86px}body{margin:0;background:var(--bg);color:var(--body);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif}body.drawer-open{overflow:hidden}a{color:var(--deep);text-decoration:none}a:hover{color:var(--blue)}button{font:inherit}img{max-width:100%}.wrap{max-width:1160px;margin:0 auto;padding-left:24px;padding-right:24px}.skip-link{position:absolute;top:-100px;left:20px;z-index:1000;background:white;padding:8px 16px}.skip-link:focus{top:10px}.site-header{background:#fff;border-bottom:1px solid var(--border);position:sticky;top:0;z-index:50}.header-inner{height:72px;display:flex;align-items:center;gap:26px}.brand{display:flex;align-items:center;flex-shrink:0;min-width:155px}.brand img{display:block;max-height:38px;width:auto;max-width:190px;object-fit:contain}.brand-fallback{display:flex;align-items:baseline;gap:7px;font-size:24px;color:var(--deep);white-space:nowrap}.brand-fallback b{background:linear-gradient(110deg,var(--cyan),var(--blue));background-clip:text;-webkit-background-clip:text;color:transparent}.brand-fallback small{font-size:10px;letter-spacing:.04em}.desktop-nav{display:flex;align-items:center;justify-content:center;gap:17px;flex:1;white-space:nowrap}.desktop-nav a{font-size:14px;font-weight:650;display:inline-flex;height:72px;align-items:center;border-bottom:3px solid transparent;padding-top:3px}.desktop-nav a.active,.desktop-nav a[aria-current]{color:var(--blue);border-bottom-color: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}.main-btn:hover{color:white;filter:brightness(1.05)}.menu-trigger{display:none;align-items:center;justify-content:center;flex-direction:column;gap:5px;width:42px;height:42px;border:1px solid var(--border);border-radius:11px;background:white;cursor:pointer}.menu-trigger span{width:19px;height:2px;background:var(--ink);border-radius:2px}.drawer-overlay{position:fixed;inset:0;background:rgba(11,36,60,.46);opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s,visibility .2s;z-index:70}.drawer{position:fixed;top:0;left:0;bottom:0;width:min(86vw,340px);z-index:71;background:#fff;transform:translateX(-103%);visibility:hidden;transition:transform .24s,visibility .24s;overflow-y:auto;padding:22px;box-shadow:20px 0 40px rgba(0,0,0,.09)}.drawer-open .drawer-overlay{opacity:1;visibility:visible;pointer-events:auto}.drawer-open .drawer{transform:translateX(0);visibility:visible}.drawer-head{display:flex;justify-content:space-between;align-items:center;font-size:20px;color:var(--ink);margin-bottom:20px}.drawer-close{border:0;background:var(--soft);width:38px;height:38px;border-radius:10px;color:var(--ink);font-size:27px;cursor:pointer;line-height:1}.drawer-heading{margin:24px 0 5px;color:var(--muted);font-size:12px;font-weight:700;letter-spacing:.08em}.drawer nav a{display:block;padding:11px 6px;border-bottom:1px solid var(--border);font-weight:650}.drawer nav a[aria-current]{color:var(--blue)}.section{padding-top:48px;padding-bottom:12px}.section:last-child{padding-bottom:54px}.eyebrow{color:#117c9f;font-weight:800;font-size:13px;letter-spacing:.12em;text-transform:uppercase}.hero{padding-top:42px}.hero-grid{display:grid;grid-template-columns:1.07fr .93fr;align-items:center;gap:38px}.hero-copy{padding:32px 0}.hero h1{font-size:40px;line-height:1.34;letter-spacing:-.025em;margin:12px 0 20px;color:var(--ink)}h1,h2,h3{color:var(--ink);line-height:1.4}h2{font-size:26px;margin:0 0 16px}h3{font-size:20px;margin:0 0 9px}.lead{font-size:17px;line-height:1.85;color:#466077;max-width:740px}.hero .lead{margin-bottom:26px}.hero-actions{display:flex;gap:13px;flex-wrap:wrap;align-items:center}.text-link{font-weight:700;color:var(--blue)}.pill-note{display:inline-flex;border:1px solid #bee8f0;background:var(--soft);border-radius:99px;padding:5px 13px;font-size:13px;color:#166989}.media{width:100%;display:flex;justify-content:center;align-items:center;overflow:hidden;border-radius:15px;background:var(--soft);border:1px solid var(--border);min-height:180px}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.media-hero{height:315px}.media-landscape{height:235px}.media-card{height:166px}.media-portrait{height:325px}.media-placeholder{width:100%;height:100%;min-height:inherit;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:16px;color:#56809a;padding:24px;background:radial-gradient(circle at 20% 20%,#fff 0,transparent 50%),linear-gradient(135deg,#dcf6fb,#ecf7fd)}.placeholder-mark{width:58px;height:58px;border:3px solid #8edee8;border-radius:15px;transform:rotate(-8deg);position:relative}.placeholder-mark:after{content:'';position:absolute;inset:15px;border:3px solid #92cde8;border-radius:50%}.section-head{display:flex;justify-content:space-between;gap:18px;align-items:end;margin-bottom:22px}.section-head p{margin:0;max-width:600px;color:var(--muted)}.card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.info-card{background:white;border:1px solid var(--border);border-radius:14px;padding:25px;box-shadow:var(--shadow);min-width:0}.info-card h3{margin-top:9px}.info-card p{margin:0 0 13px}.info-card a.more{font-weight:700;color:var(--blue)}.card-index{display:inline-flex;border-radius:7px;background:var(--soft2);color:#137da5;font-size:12px;letter-spacing:.06em;font-weight:800;padding:3px 9px}.editor-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:20px}.panel{background:#fff;border:1px solid var(--border);border-radius:16px;padding:28px}.panel-accent{background:linear-gradient(125deg,#e6fafc,#fff)}.panel p:first-child{margin-top:0}.editor-list{display:grid;gap:14px}.editor-item{padding:18px 20px;background:white;border:1px solid var(--border);border-radius:13px}.editor-item h3{font-size:18px}.editor-item p{margin:0;font-size:15px}.topic-strip{display:flex;flex-wrap:wrap;gap:10px}.topic-strip a{border:1px solid var(--border);border-radius:99px;padding:8px 15px;background:#fff;font-size:14px;font-weight:700}.wide-feature{display:grid;grid-template-columns:1fr 1fr;align-items:center;gap:27px;background:white;border:1px solid var(--border);border-radius:18px;padding:23px}.wide-feature p{margin:10px 0 18px}.prose{max-width:820px}.article-shell{padding-top:42px}.article-head{max-width:850px;margin:0 auto 30px}.article-head h1{font-size:34px;margin:12px 0 15px}.article-body{max-width:820px;margin:0 auto}.article-body p{margin:0 0 18px}.article-body h2{margin-top:40px}.article-body h3{margin-top:24px}.article-body ul,.article-body ol{padding-left:1.45em;margin-top:10px;margin-bottom:22px}.article-body li{margin:6px 0}.article-body .media{margin:22px 0 26px}.article-intro{border-left:4px solid var(--cyan);padding:12px 22px;background:var(--soft);border-radius:0 11px 11px 0}.split-feature{display:grid;grid-template-columns:1fr 1fr;gap:25px;align-items:center;margin:32px 0}.split-feature p{margin:0 0 15px}.comparison{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin:20px 0 30px}.comparison>.panel{padding:23px}.label-bar{margin-top:16px;color:#0c8198;font-size:13px;font-weight:800;letter-spacing:.05em}.fact-table{width:100%;border-collapse:collapse;margin:22px 0 28px;font-size:15px;background:white}.fact-table caption{text-align:left;font-weight:700;margin-bottom:8px;color:var(--ink)}.fact-table th,.fact-table td{padding:13px 14px;border:1px solid var(--border);text-align:left;vertical-align:top}.fact-table th{background:var(--soft);color:var(--ink);width:28%}.note-box{background:var(--soft);border:1px solid #c8ecf0;border-radius:14px;padding:18px 22px;margin:27px 0}.note-box strong{color:var(--ink)}.number-steps{counter-reset:step;list-style:none;padding-left:0!important}.number-steps li{position:relative;padding:12px 14px 12px 56px;border-bottom:1px solid var(--border);counter-increment:step}.number-steps li:before{content:counter(step,decimal-leading-zero);position:absolute;left:4px;top:15px;color:var(--blue);font-weight:800}.anchor-row{display:flex;gap:10px;flex-wrap:wrap;margin:18px 0 28px}.anchor-row a{padding:7px 13px;background:var(--soft);border:1px solid var(--border);border-radius:8px;font-size:14px;font-weight:650}.related{max-width:820px;margin:48px auto 60px;border-top:1px solid var(--border);padding-top:26px}.related-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.related-link{padding:16px;background:#fff;border:1px solid var(--border);border-radius:11px;display:flex;justify-content:space-between;gap:12px;font-weight:700}.faq-item{padding:20px 0;border-bottom:1px solid var(--border)}.faq-item h3{font-size:18px;margin:0 0 7px}.faq-item p{margin:0}.site-footer{background:var(--footer);color:#eaf7ff;margin-top:30px;padding-top:48px}.site-footer h2{color:white;font-size:18px}.footer-layout{display:grid;grid-template-columns:1.2fr 1fr 1fr;gap:45px}.footer-layout p{font-size:14px;color:#d0e4f0}.footer-logo{font-size:23px;font-weight:800;color:white}.footer-logo small{font-size:10px;font-weight:600;letter-spacing:.08em;margin-left:4px}.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}.footer-links a,.footer-bottom a{color:#eaf7ff;font-size:14px}.footer-bottom{border-top:1px solid rgba(255,255,255,.14);margin-top:32px;padding-top:18px;padding-bottom:20px;display:flex;justify-content:space-between;gap:15px;font-size:13px}.mobile-bottom{display:none}.back-top{position:fixed;right:25px;bottom:26px;width:43px;height:43px;border:0;border-radius:50%;background:var(--blue);color:white;font-size:21px;box-shadow:var(--shadow);cursor:pointer;opacity:0;pointer-events:none;transition:opacity .2s;z-index:40}.back-top.show{opacity:1;pointer-events:auto}:focus-visible{outline:3px solid #16a0c9;outline-offset:3px}@media(max-width:1100px){.desktop-nav{gap:10px}.desktop-nav a{font-size:13px}.brand{min-width:135px}.header-inner{gap:14px}}@media(max-width:980px){.header-inner{height:60px;justify-content:space-between}.menu-trigger{display:flex}.desktop-nav{display:none}.brand{min-width:0;position:absolute;left:50%;transform:translateX(-50%);max-width:42%}.brand img{max-height:30px;max-width:100%}.brand-fallback{font-size:21px}.brand-fallback small{font-size:8px}.header-cta{height:40px;padding:0 13px;font-size:13px}.hero-grid{grid-template-columns:1fr 1fr;gap:20px}.hero h1{font-size:32px}.card-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.footer-layout{grid-template-columns:1fr 1fr}}@media(max-width:680px){body{font-size:15px}.wrap{padding-left:16px;padding-right:16px}.section{padding-top:30px;padding-bottom:6px}.section:last-child{padding-bottom:32px}.hero{padding-top:20px}.hero-grid{grid-template-columns:1fr}.hero-grid .media{order:-1}.hero-copy{padding:5px 0}.hero h1{font-size:29px}.lead{font-size:15.5px}.media-hero{height:210px}.media-landscape{height:185px}.media-card{height:150px}.media-portrait{height:290px}h2{font-size:22px}h3{font-size:18px}.section-head{display:block}.card-grid,.editor-grid,.comparison,.split-feature,.wide-feature,.related-grid,.footer-layout{grid-template-columns:1fr}.info-card{padding:20px}.panel{padding:21px}.wide-feature{padding:16px;gap:14px}.article-shell{padding-top:23px}.article-head h1{font-size:27px}.article-head{margin-bottom:20px}.article-body h2{margin-top:31px}.article-body .media{margin:18px 0 21px}.fact-table{font-size:14px}.fact-table th,.fact-table td{padding:10px}.footer-layout{gap:20px}.site-footer{padding-top:36px}.footer-bottom{padding-bottom:85px}.mobile-bottom{display:grid;grid-template-columns:repeat(4,1fr);position:fixed;bottom:0;left:0;right:0;z-index:48;background:#fff;border-top:1px solid var(--border);padding:7px 8px max(7px,env(safe-area-inset-bottom))}.mobile-bottom a{display:block;text-align:center;font-size:13px;font-weight:750;padding:5px;color:var(--deep)}.mobile-bottom a[aria-current]{color:var(--blue)}.back-top{bottom:78px;right:15px}.brand-fallback small{display:none}.header-cta{min-width:78px}.footer-links{grid-template-columns:repeat(2,1fr)}}@media(max-width:360px){.brand-fallback{font-size:18px}.header-cta{padding:0 9px;min-width:68px;font-size:12px}.hero h1{font-size:27px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important}}