:root{--bg:#f5fbff;--white:#fff;--ice:#eaf7fc;--mist:#dff5fb;--cyan:#25c8d1;--sky:#25b6e8;--blue:#1787db;--navy:#174b78;--ink:#173b60;--body:#2d4359;--muted:#687f93;--line:#dcebf3;--footer:#123653;--shadow:0 13px 44px rgba(20,83,122,.07)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:90px}body{margin:0;background:var(--bg);color:var(--body);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;line-height:1.8;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}a:hover{color:var(--blue)}button{font:inherit;cursor:pointer}img{display:block;max-width:100%}.wrap{width:min(1160px,calc(100% - 48px));margin:0 auto}.skip-link{position:absolute;z-index:200;left:12px;top:-60px;padding:8px 14px;background:#fff}.skip-link:focus{top:8px}.site-header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:60}.header-inner{height:72px;display:flex;align-items:center;gap:24px}.brand{display:flex;align-items:center;flex:none;max-width:220px}.brand-logo{max-width:190px;width:auto;height:auto;max-height:38px;object-fit:contain}.brand-text{display:grid;font-size:21px;font-weight:900;line-height:1.15;color:var(--ink);letter-spacing:.04em}.brand-text small{font-size:9px;letter-spacing:.2em;color:var(--blue);margin-top:5px}.desktop-nav{display:flex;align-items:center;gap:clamp(10px,1.5vw,23px);margin-left:auto;white-space:nowrap}.desktop-nav a{font-size:14px;font-weight:700;color:var(--ink);padding:24px 0 21px;border-bottom:3px solid transparent}.desktop-nav a:hover,.desktop-nav .is-active{color:var(--blue);border-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;box-shadow:0 7px 20px rgba(37,182,232,.19)}.main-btn:hover{color:#fff;filter:brightness(.95)}.header-cta{margin-left:4px;font-size:14px}.menu-toggle{display:none;border:0;background:transparent;width:42px;height:42px;align-items:center;justify-content:center;flex-direction:column;gap:5px}.menu-toggle 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span{display:block;color:var(--blue);font-size:13px;font-weight:800;margin-bottom:3px}.drawer-group a{display:block;padding:9px 4px;color:var(--ink);font-weight:600;font-size:15px}.eyebrow{display:inline-block;color:var(--blue);font-weight:800;letter-spacing:.13em;font-size:12px;text-transform:uppercase}.hero{padding:54px 0 48px;background:radial-gradient(ellipse at 95% 10%,#d4f6fc 0%,transparent 50%),linear-gradient(180deg,#f5fbff,#fff)}.hero-inner{display:grid;grid-template-columns:1.1fr .9fr;gap:45px;align-items:center}.hero h1{font-size:clamp(30px,3.1vw,40px);line-height:1.38;color:var(--ink);letter-spacing:-.025em;margin:18px 0}.hero p{font-size:17px;max-width:640px;line-height:1.85;margin:0 0 22px}.hero-actions{display:flex;flex-wrap:wrap;gap:12px}.secondary-btn{display:inline-flex;align-items:center;justify-content:center;min-height:42px;padding:0 19px;border-radius:999px;border:1px solid #a6dce9;color:var(--navy);font-weight:700;background:#fff}.hero-chips{display:flex;gap:8px;flex-wrap:wrap;margin-top:25px}.hero-chips span{font-size:12px;background:#e5f6fa;color:var(--navy);border:1px solid var(--line);border-radius:999px;padding:4px 11px}.media{display:flex;align-items:center;justify-content:center;width:100%;overflow:hidden;background:var(--ice);border-radius:14px;position:relative}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.media--fallback{background:linear-gradient(140deg,#eaf7fc 0%,#d7f2f9 50%,#e0f6fd 100%);border:1px solid #d2e9f4}.media__ornament{width:40%;aspect-ratio:1;border:2px solid rgba(37,182,232,.23);border-radius:50%;position:relative}.media__ornament:before,.media__ornament:after{content:"";position:absolute;inset:18%;border:2px solid rgba(23,135,219,.2);border-radius:50%}.media__ornament:after{inset:-22%;border-style:dashed;opacity:.6}.hero-media{height:310px}.feature-media{height:220px}.tile-media{height:165px}.portrait-media{height:300px;max-width:360px}.page-banner{padding:51px 0 38px;background:linear-gradient(115deg,#eaf7fc,#f5fbff 65%);border-bottom:1px solid var(--line)}.page-banner .wrap{max-width:1160px}.page-banner h1{font-size:clamp(26px,3vw,34px);line-height:1.4;margin:10px 0 13px;color:var(--ink)}.page-banner p{max-width:830px;font-size:17px;margin:0}.page-section{padding:46px 0}.page-section.alt{background:#fff}.section-heading{margin-bottom:23px}.section-heading h2{font-size:clamp(21px,2.4vw,26px);line-height:1.4;color:var(--ink);margin:7px 0 9px}.section-heading p{margin:0;max-width:780px}.content-narrow{max-width:820px}.prose{font-size:16px;line-height:1.83}.prose h2{font-size:25px;color:var(--ink);margin:37px 0 13px;line-height:1.45}.prose h3{font-size:19px;color:var(--ink);margin:26px 0 7px;line-height:1.4}.prose p{margin:0 0 16px}.prose ul,.prose ol{padding-left:1.4em}.prose li{margin:8px 0}.prose a{text-decoration:underline;text-underline-offset:3px;color:var(--blue)}.card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.card{border-radius:15px;background:#fff;border:1px solid var(--line);padding:23px;box-shadow:var(--shadow)}.card .num{font-size:12px;color:var(--blue);font-weight:800;letter-spacing:.1em}.card h3{font-size:19px;line-height:1.45;color:var(--ink);margin:8px 0}.card p{font-size:15px;line-height:1.8;margin:0 0 10px}.card a{font-weight:800;color:var(--blue);font-size:14px}.card-media{padding:0;overflow:hidden}.card-media .media{border-radius:14px 14px 0 0}.card-media .card-body{padding:21px}.feature-split{display:grid;grid-template-columns:1fr 1fr;gap:36px;align-items:center}.feature-split.reverse .feature-copy{order:2}.feature-split.reverse .media{order:1}.feature-copy 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18px}.related-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:15px}.related-link{position:relative;display:flex;flex-direction:column;min-height:132px;padding:19px 38px 19px 19px;background:#fff;border:1px solid var(--line);border-radius:12px}.related-link strong{font-size:17px;color:var(--ink)}.related-link span:not(.link-arrow){font-size:13px;color:var(--muted);margin-top:7px}.related-link .link-arrow{position:absolute;right:15px;top:14px;color:var(--blue)}.faq details{border-bottom:1px solid var(--line);padding:16px 0;background:#fff}.faq details:first-child{border-top:1px solid var(--line)}.faq summary{cursor:pointer;color:var(--ink);font-weight:800;line-height:1.6;padding-right:28px}.faq details p{margin:12px 0 0;font-size:15px}.site-footer{background:var(--footer);color:#eaf7ff;margin-top:0}.footer-main{display:grid;grid-template-columns:1.3fr 1.2fr 1fr;gap:54px;padding:46px 0 34px}.footer-brand .brand-logo{max-height:37px}.footer-brand 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@media(max-width:1080px){.header-inner{gap:12px}.desktop-nav{gap:10px}.desktop-nav a{font-size:13px}.brand-logo{max-width:155px}}
@media(max-width:980px){.desktop-nav{display:none}.menu-toggle{display:flex}.header-inner{justify-content:space-between;height:60px}.brand{position:absolute;left:50%;transform:translateX(-50%);max-width:150px}.brand-logo{max-width:135px;max-height:30px}.brand-text{font-size:17px}.brand-text small{font-size:7px}.header-cta{margin-left:auto;height:40px;padding:0 14px;font-size:13px}.footer-brand{position:static;transform:none}.hero-inner{gap:22px}.hero-media{height:265px}.split-content{grid-template-columns:1fr}.sidebar{position:static;display:none}}
@media(max-width:700px){body{font-size:15px;padding-bottom:60px}.wrap{width:calc(100% - 32px)}.hero{padding:28px 0 36px}.hero-inner{grid-template-columns:1fr;gap:21px}.hero-media{grid-row:1;height:210px}.hero h1{font-size:29px;margin:9px 0 11px}.hero p{font-size:15px}.page-banner{padding:31px 0 28px}.page-banner h1{font-size:26px}.page-banner p{font-size:15px}.page-section{padding:31px 0}.section-heading h2{font-size:22px}.section-heading{margin-bottom:17px}.card-grid,.comparison,.related-grid,.index-grid{grid-template-columns:1fr}.card{padding:20px}.card-media{padding:0}.feature-split{grid-template-columns:1fr;gap:18px}.feature-split.reverse .feature-copy{order:0}.feature-split.reverse .media{order:0}.feature-copy h2{font-size:22px}.feature-media{height:190px}.portrait-media{height:230px;max-width:100%}.prose{font-size:15px}.prose h2{font-size:21px;margin:25px 0 9px}.prose h3{font-size:18px}.footer-main{grid-template-columns:1fr;gap:24px;padding:35px 0 22px}.footer-bottom{flex-direction:column;gap:5px}.bottom-nav{position:fixed;z-index:50;bottom:0;left:0;right:0;height:59px;background:#fff;border-top:1px solid var(--line);display:grid;grid-template-columns:repeat(4,1fr)}.bottom-nav a{display:grid;place-items:center;color:var(--navy);font-size:13px;font-weight:800}.bottom-nav a:hover{color:var(--blue)}.back-to-top{bottom:71px;right:12px;width:38px;height:38px}.editorial-item{grid-template-columns:45px 1fr;gap:13px}.editorial-item .ordinal{font-size:25px}.info-table{font-size:13px}.info-table td,.info-table th{padding:10px}.related{padding:31px 0}.hero-chips{margin-top:18px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important}}
