:root{--bg:#f4f7fa;--paper:#fff;--soft:#eaf1f6;--aqua:#e9f8f8;--nav:#102e46;--nav2:#163c57;--teal:#13b8c5;--blue:#237bd3;--heading:#18364b;--body:#344c60;--muted:#64798a;--line:#dce6ed;--footer:#0b2539;--gutter:28px}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--body);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;font-size:16px;line-height:1.8;overflow-x:hidden}a{color:#1769b2;text-underline-offset:3px}a:hover{color:#095384}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #13b8c5;outline-offset:3px}button{font:inherit;cursor:pointer}.container{width:min(100% - 2*var(--gutter),1200px);margin-inline:auto}.reading{max-width:800px}.wide-reading{max-width:1000px}h1,h2,h3{color:var(--heading);line-height:1.38;margin:0 0 .7em}h1{font-size:clamp(32px,3.1vw,36px);letter-spacing:-.025em}h2{font-size:clamp(24px,2.2vw,28px)}h3{font-size:20px}p{margin:0 0 1.1em}section{scroll-margin-top:25px}.section-space{margin-block:56px}.eyebrow{color:#157c89;font-size:13px;font-weight:700;letter-spacing:.09em;text-transform:uppercase;margin:0 0 10px}.lead{font-size:17px;line-height:1.85}.muted{color:var(--muted)}.skip-link{position:fixed;top:-90px;left:12px;z-index:300;background:white;padding:10px}.skip-link:focus{top:12px}.site-header{position:relative;z-index:15}.brand-bar{background:var(--nav);color:#f2fbff}.brand-inner{height:72px;display:flex;gap:18px;align-items:center;min-width:0}.brand{display:inline-flex;align-items:center;min-width:0;text-decoration:none}.brand .media-frame{background:transparent;padding:0;border:0;min-height:0}.brand .media-frame img{max-height:38px;width:auto;max-width:min(200px,100%)}.brand-fallback{color:white;font-size:21px;white-space:nowrap;font-weight:800;line-height:1.1}.brand-fallback small,.footer-brand small{font-size:10px;letter-spacing:.1em;display:block;font-weight:500}.brand-tagline{font-size:13px;color:#b5d5e3;white-space:nowrap}.registration-link{margin-left:auto;background:var(--teal);color:#073142;text-decoration:none;border-radius:8px;padding:8px 20px;font-size:14px;font-weight:700;white-space:nowrap}.registration-link:hover{background:#62d6dc;color:#082b3b}.desktop-nav{background:var(--nav);border-top:1px solid #315168}.nav-inner{min-height:50px;display:grid;grid-template-columns:repeat(7,minmax(0,1fr));align-items:stretch;gap:5px}.desktop-nav a{display:flex;align-items:center;justify-content:center;color:#d5e6ef;text-align:center;font-size:14px;text-decoration:none;font-weight:600;white-space:nowrap;position:relative;padding:8px 2px}.desktop-nav a:hover{color:white}.desktop-nav a[aria-current=page]{color:#fff;font-weight:800}.desktop-nav a[aria-current=page]:after{content:"";position:absolute;bottom:0;left:24%;right:24%;height:3px;background:var(--teal)}.menu-toggle{display:none}.nojs-nav{display:none}.drawer-overlay,.mobile-drawer{display:none}.breadcrumbs{display:flex;gap:12px;color:var(--muted);font-size:13px;margin:25px 0 16px}.breadcrumbs a{color:var(--muted)}.page-intro{padding:8px 0 25px;border-bottom:1px solid var(--line)}.page-intro p{max-width:820px}.page-body{padding-bottom:45px}.content-section{margin-top:50px}.content-section p{max-width:790px}.page-grid{display:grid;grid-template-columns:minmax(0,1fr) 245px;gap:38px;align-items:start}.page-grid>*{min-width:0}.sidebar-note{background:var(--aqua);border-top:4px solid var(--teal);padding:23px;border-radius:0 0 12px 12px;font-size:14px}.sidebar-note h3{font-size:18px}.soft-panel{background:var(--soft);padding:24px;border:1px solid var(--line);border-radius:12px}.dark-panel{background:var(--nav2);padding:28px;color:#e8f7ff;border-radius:12px}.dark-panel h2,.dark-panel h3{color:#fff}.section-kicker{font-size:13px;font-weight:bold;color:#157c89;text-transform:uppercase;letter-spacing:.08em}.tag{display:inline-block;border:1px solid #b8d2df;border-radius:100px;padding:1px 10px;color:#335568;font-size:13px;margin-bottom:10px}.anchor-nav{display:flex;flex-wrap:wrap;gap:10px;margin:25px 0}.anchor-nav a{display:inline-block;padding:8px 15px;border-radius:7px;background:#eaf1f6;border:1px solid var(--line);text-decoration:none;font-weight:700;font-size:14px}.anchor-nav a:hover{background:#dbf4f4}.media-frame{display:flex;align-items:center;justify-content:center;width:100%;min-width:0;margin:0;background:var(--soft);padding:8px;border:1px solid var(--line);border-radius:14px}.media-frame img{display:block;width:auto;height:auto;max-width:100%;max-height:var(--media-limit,220px);object-fit:contain;object-position:center}.media-frame--logo{background:transparent;border:none;padding:0;--media-limit:38px}.media-frame--hero{--media-limit:310px}.media-frame--feature{--media-limit:250px}.media-frame--card{--media-limit:185px}.media-frame--mobile{--media-limit:350px;max-width:320px;margin-inline:auto}.media-frame--banner{--media-limit:210px}.media-missing{min-height:110px;color:#7794a5;font-size:13px;text-align:center;background:repeating-linear-gradient(135deg,#eaf1f6,#eaf1f6 12px,#edf4f8 12px,#edf4f8 24px)}.media-frame--hero.media-missing{min-height:190px}.media-frame--logo.media-missing{min-height:0}.media-frame--logo.media-missing span{font-size:12px}.two-col{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:35px;align-items:center}.two-col>*{min-width:0}.three-col{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.three-col>*{min-width:0}.split-65{display:grid;grid-template-columns:minmax(0,1.7fr) minmax(0,1fr);gap:25px}.split-65>*{min-width:0}.plain-list{padding-left:21px}.plain-list li{margin-bottom:9px}.numbered-steps{counter-reset:step;list-style:none;padding:0;margin:24px 0}.numbered-steps li{counter-increment:step;position:relative;padding:0 0 24px 58px;margin-bottom:20px;border-bottom:1px solid var(--line)}.numbered-steps li:before{content:counter(step,decimal-leading-zero);position:absolute;left:0;top:0;font-weight:800;color:#137f8b;font-size:24px}.numbered-steps li strong{display:block;color:var(--heading);font-size:19px}.compare-table{overflow-x:auto;max-width:100%;border:1px solid var(--line);border-radius:10px;margin:18px 0 28px}table{width:100%;border-collapse:collapse;font-size:15px;background:white}caption{text-align:left;color:var(--heading);font-weight:700;padding:13px 15px}th,td{text-align:left;vertical-align:top;border-bottom:1px solid var(--line);padding:13px 16px}th{color:var(--heading);background:#eaf1f6;font-weight:700}tr:last-child td{border-bottom:0}.related-section{margin-block:65px 30px;padding-top:26px;border-top:2px solid var(--line)}.related-links{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.related-links a{border:1px solid var(--line);background:#fff;border-radius:10px;padding:20px;display:flex;flex-direction:column;gap:8px;text-decoration:none;color:var(--body)}.related-links a strong{color:var(--heading);font-size:17px}.related-links a span:nth-child(2){font-size:13px;line-height:1.6;color:var(--muted)}.related-links a span:last-child{align-self:flex-end;color:#138a94}.related-links a:hover{border-color:var(--teal)}.hero{display:grid;grid-template-columns:minmax(0,1.08fr) minmax(0,1fr);gap:35px;align-items:center;padding:47px 0}.hero>*{min-width:0}.hero h1{font-size:clamp(38px,3.5vw,44px);margin-bottom:22px}.hero p{max-width:590px}.actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:20px}.button-link{display:inline-block;padding:10px 20px;background:var(--nav);color:white!important;text-decoration:none;border-radius:8px;font-size:14px;font-weight:700}.button-link.secondary{background:#e4f5f5;color:#0e626a!important}.topic-directory{background:#fff;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:44px 0}.topic-index{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 44px}.topic-index article{padding:22px 0;border-top:1px solid var(--line)}.topic-index article h3{margin-bottom:5px}.topic-index article p{font-size:14px;margin-bottom:8px}.topic-index article a{font-weight:700}.focus-feature{background:#fff;padding:27px;border-left:5px solid var(--teal)}.focus-side{padding:18px 0;border-bottom:1px solid var(--line)}.focus-side h3{font-size:18px}.flow-strip{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}.flow-strip a{background:white;border-top:3px solid var(--teal);padding:16px;color:var(--heading);font-weight:700;text-decoration:none}.flow-strip small{display:block;font-weight:400;color:var(--muted)}.editor-note{font-size:14px;color:var(--muted);border-top:1px solid var(--line);padding:24px 0}.gallery-item{margin-bottom:32px}.gallery-item p{font-size:14px;margin:12px 0}.gallery-stagger>*:nth-child(even){margin-top:45px}.faq details{border-bottom:1px solid var(--line);background:#fff;padding:16px 20px}.faq details:first-of-type{border-radius:10px 10px 0 0}.faq details:last-of-type{border-radius:0 0 10px 10px}.faq summary{font-weight:700;cursor:pointer;color:var(--heading)}.faq details p{margin:12px 0 2px;font-size:15px}.service-layout{display:grid;grid-template-columns:235px minmax(0,1fr);gap:35px;align-items:start}.service-layout>*{min-width:0}.service-nav{padding:22px;background:var(--soft);border:1px solid var(--line);border-radius:10px}.service-nav a{display:block;padding:8px 0;text-decoration:none;border-bottom:1px solid var(--line)}.service-nav a:last-child{border-bottom:0}.mobile-quick{display:none}.site-footer{background:var(--footer);color:#dcecf5;padding:42px 0 16px}.footer-layout{display:grid;grid-template-columns:1.3fr 1fr;gap:60px}.footer-brand{font-size:23px;font-weight:800;color:white;text-decoration:none}.footer-note{font-size:13px;color:#b6cdda;max-width:530px}.footer-nav{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:5px 20px;margin-top:12px}.footer-nav a{color:#dcecf5;text-decoration:none;font-size:14px}.footer-bottom{border-top:1px solid #365266;display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;padding-top:14px;margin-top:26px;font-size:12px;color:#b6cdda}.footer-bottom a{color:#b6cdda}.back-to-top{position:fixed;right:20px;bottom:25px;z-index:10;width:42px;height:42px;border:0;border-radius:50%;background:var(--nav);color:white;box-shadow:0 2px 9px #102e4626}.back-to-top[hidden]{display:none}
@media(max-width:1200px){:root{--gutter:22px}.two-col{gap:24px}.hero{gap:25px}}
@media(max-width:920px){.brand-inner{height:62px;justify-content:space-between;gap:10px}.menu-toggle{display:flex;flex-direction:column;justify-content:center;align-items:center;gap:5px;flex:0 0 40px;width:40px;height:40px;background:transparent;color:white;border:1px solid #52758b;border-radius:8px}.menu-toggle span{display:block;width:18px;height:2px;background:#fff}.brand-tagline,.desktop-nav{display:none}.brand{flex:0 1 auto;max-width:43vw}.brand .media-frame img{max-height:30px;max-width:100%}.brand-fallback{font-size:17px}.brand-fallback small{font-size:8px}.registration-link{margin:0;padding:8px 10px;font-size:13px;min-height:40px;display:flex;align-items:center}.drawer-overlay{display:block;position:fixed;inset:0;z-index:40;background:#081a27a6;opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s,visibility .2s}.mobile-drawer{display:block;position:fixed;inset:0 auto 0 0;z-index:41;width:min(86vw,340px);height:100dvh;background:white;transform:translateX(-102%);visibility:hidden;pointer-events:none;transition:transform .22s,visibility .22s;overflow-y:auto;box-shadow:10px 0 40px #102e4624}.drawer-open .drawer-overlay{opacity:1;visibility:visible;pointer-events:auto}.drawer-open .mobile-drawer{transform:translateX(0);visibility:visible;pointer-events:auto}.drawer-head{display:flex;align-items:center;justify-content:space-between;padding:18px 20px;border-bottom:1px solid var(--line)}.drawer-close{background:var(--soft);color:var(--nav);border:0;border-radius:7px;width:40px;height:40px;font-size:28px;line-height:1}.mobile-drawer nav{padding:12px 20px 35px}.drawer-group{color:#698092;font-weight:700;font-size:12px;letter-spacing:.1em;margin:17px 0 5px}.mobile-drawer nav a{display:block;color:var(--heading);padding:10px 12px;margin:2px 0;text-decoration:none;border-radius:7px;font-weight:700}.mobile-drawer nav a:hover{background:var(--soft)}.nojs-nav{display:block;background:#eaf1f6}.nojs-nav .container{display:flex;flex-wrap:wrap;gap:8px 16px;padding:10px 0}.nojs-nav a{font-size:13px}.mobile-quick{display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px;padding:18px 0;margin-top:20px;border-top:1px solid var(--line);font-size:13px}.page-grid{grid-template-columns:minmax(0,1fr) 190px;gap:20px}}
@media(max-width:760px){.two-col,.page-grid,.split-65,.service-layout,.footer-layout{grid-template-columns:minmax(0,1fr)}.page-grid .sidebar-note{margin-top:15px}.service-nav{order:2}.service-main{order:1}.related-links{grid-template-columns:1fr}.three-col{grid-template-columns:repeat(2,minmax(0,1fr))}.flow-strip{grid-template-columns:repeat(2,minmax(0,1fr))}.gallery-stagger>*:nth-child(even){margin-top:0}.hero{grid-template-columns:minmax(0,1fr);padding:34px 0}.hero .media-frame{max-width:660px}.footer-layout{gap:22px}}
@media(max-width:640px){:root{--gutter:16px}body{font-size:15px;line-height:1.8}h1{font-size:clamp(25px,7vw,29px)}h2{font-size:clamp(20px,5.5vw,23px)}h3{font-size:18px}.hero h1{font-size:clamp(27px,7.3vw,32px)}.lead{font-size:16px}.section-space{margin-block:36px}.content-section{margin-top:36px}.topic-index,.three-col{grid-template-columns:minmax(0,1fr)}.topic-directory{padding:30px 0}.topic-index article{padding:17px 0}.dark-panel,.soft-panel,.focus-feature{padding:18px}.media-frame--hero{--media-limit:205px}.media-frame--feature{--media-limit:185px}.media-frame--card{--media-limit:145px}.media-frame--mobile{--media-limit:285px;max-width:250px}.media-frame--banner{--media-limit:135px}.media-frame--logo{--media-limit:30px}.page-intro{padding-bottom:14px}.related-section{margin-block:40px 20px}.compare-table th,.compare-table td{padding:10px;min-width:110px;font-size:13px}.brand-fallback{font-size:15px}.registration-link{font-size:12px}.footer-nav{gap:5px 14px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;animation-duration:.01ms!important;transition-duration:.01ms!important}}