:root{--base:#f6fafc;--white:#fff;--pale:#eaf6fa;--soft:#edf4f8;--cyan:#25c8d1;--sky:#25b6e8;--blue:#1787db;--navy:#174b78;--title:#183a56;--body:#31485d;--muted:#687d8e;--border:#dce9f0;--footer:#123653;font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--body);background:var(--base)}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;overflow-x:hidden;font-size:16px;line-height:1.8}a{color:#086fae;text-underline-offset:3px}a:hover{color:#04527c}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #1787db;outline-offset:3px}img{max-width:100%}h1,h2,h3,p{margin-top:0}h1,h2,h3{color:var(--title);line-height:1.38}h1{font-size:clamp(32px,3.3vw,40px);letter-spacing:-.02em}h2{font-size:26px}h3{font-size:20px}p{margin-bottom:1.1em}.wrap{width:min(1180px,calc(100% - 56px));margin-inline:auto}.narrow{max-width:780px}.section{margin-block:58px}.section-heading{margin-bottom:24px}.section-heading h2{margin:3px 0 8px}.eyebrow{display:inline-block;font-size:12px;letter-spacing:.16em;font-weight:700;color:#087f9b;text-transform:uppercase}.lead{font-size:17px;line-height:1.85}.muted{color:var(--muted)}.skip-link{position:absolute;left:12px;top:-80px;z-index:100;padding:8px 12px;background:#fff}.skip-link:focus{top:12px}.site-header{background:#fff;border-bottom:1px solid var(--border);position:relative;z-index:20}.topbar{height:72px;display:flex;align-items:center;gap:24px}.brand{display:inline-flex;align-items:center;min-width:0;text-decoration:none;color:var(--title)}.brand-logo{display:block;width:auto;height:auto;max-height:38px;max-width:220px;object-fit:contain;object-position:left center}.brand-type{font-size:25px;font-weight:800;white-space:nowrap;line-height:1.1}.brand-type small{display:block;font-size:9px;letter-spacing:.17em}.brand-subtitle{margin:0 auto;color:var(--muted);font-size:14px;letter-spacing:.08em}.entry-link{display:inline-flex;justify-content:center;align-items:center;gap:16px;min-height:42px;padding:8px 20px;border-radius:8px;background:var(--navy);color:#fff;text-decoration:none;font-weight:700;white-space:nowrap}.entry-link:hover{background:#0c669c;color:#fff}.desktop-nav{background:var(--navy)}.nav-inner{display:flex;align-items:stretch;justify-content:space-between;min-height:48px;gap:6px}.desktop-nav a{display:flex;align-items:center;color:#eaf7ff;text-decoration:none;padding:10px 13px;white-space:nowrap;font-size:14px;border-bottom:3px solid transparent}.desktop-nav a:hover,.desktop-nav a.active{color:#fff;border-bottom-color:#54dfe5;background:rgba(255,255,255,.08)}.menu-toggle{display:none}.mobile-drawer,.drawer-mask{display:none}.quick-strip{background:var(--soft);border-bottom:1px solid var(--border)}.quick-inner{display:flex;gap:26px;flex-wrap:wrap;padding-block:12px;font-size:13px}.quick-inner span{display:flex;gap:9px;flex-wrap:wrap;color:var(--navy);font-weight:700}.quick-inner a{font-weight:400;text-decoration:none}.quick-inner a:hover{text-decoration:underline}.hero{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(0,.9fr);align-items:center;gap:46px;padding-top:60px}.hero h1{font-size:clamp(35px,3.6vw,42px);margin:8px 0 20px}.hero-copy{min-width:0}.hero-copy p{max-width:620px}.hero-actions{display:flex;gap:13px;flex-wrap:wrap;margin-top:25px}.btn{display:inline-flex;align-items:center;justify-content:center;min-height:46px;padding:10px 20px;border-radius:7px;text-decoration:none;font-weight:700;background:var(--navy);color:#fff}.btn:hover{color:#fff;background:#076b9a}.btn-outline{background:transparent;border:1px solid #80bfd4;color:var(--navy)}.btn-outline:hover{color:var(--navy);background:var(--pale)}.media{display:flex;justify-content:center;align-items:center;max-width:100%;min-width:0;overflow:hidden;border-radius:14px;background:var(--pale);border:1px solid var(--border);padding:8px}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.media-placeholder{display:block;width:70%;height:64%;border:1px solid #cde6f0;border-radius:9px;background:linear-gradient(140deg,#edf9fc,#dceff6)}.media--hero{height:clamp(260px,26vw,330px)}.media--feature{height:250px}.media--card{height:170px}.media--banner{height:220px}.media--mobile{height:350px;max-width:320px}.media--small{height:190px}.topic-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.topic-item{padding:22px;background:#fff;border:1px solid var(--border);border-top:3px solid var(--cyan);text-decoration:none;border-radius:8px;min-width:0;transition:transform .2s,border-color .2s}.topic-item:hover{transform:translateY(-3px);border-color:#87cddb}.topic-item strong{display:block;color:var(--title);font-size:18px}.topic-item p{font-size:14px;margin:7px 0 0;color:var(--body)}.feature-grid{display:grid;grid-template-columns:minmax(0,2fr) minmax(0,1fr);gap:20px}.feature-main,.feature-side article,.surface{background:#fff;border:1px solid var(--border);border-radius:10px;padding:26px}.feature-main{background:linear-gradient(125deg,#fff,#eaf6fa)}.feature-main h3{font-size:24px}.feature-side{display:grid;gap:20px}.feature-side article h3{font-size:19px}.link-arrow{font-weight:700;text-decoration:none}.split{display:grid;grid-template-columns:1fr 1fr;gap:34px;align-items:center}.split.reverse .media{order:-1}.accent-band{background:var(--pale);padding:42px 0}.editorial h3{margin-bottom:7px}.column-three{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.knowledge-block{border-left:3px solid var(--cyan);padding:12px 20px;background:#fff}.steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;counter-reset:steps}.step{padding:20px;background:var(--soft);border:1px solid var(--border);border-radius:8px}.step::before{counter-increment:steps;content:'0' counter(steps);display:block;color:#0a8597;font-weight:800;font-size:24px}.page-heading{padding:52px 0 28px}.page-heading h1{margin:8px 0 16px;font-size:35px}.page-heading .lead{max-width:850px}.article-body{max-width:780px}.article-body p{line-height:1.83}.article-body h2{margin-top:33px}.article-body h3{margin-top:24px}.prose-layout{display:grid;grid-template-columns:minmax(0,760px) minmax(0,240px);gap:40px;align-items:start}.sidebar{background:var(--pale);padding:23px;border-radius:10px;border:1px solid var(--border)}.sidebar h2{font-size:20px}.sidebar dl{margin:0}.sidebar dt{font-weight:700;color:var(--title);margin-top:15px}.sidebar dd{margin:0;font-size:14px}.comparison,.table-scroll{overflow-x:auto;border:1px solid var(--border);border-radius:8px;background:#fff}.comparison table,.table-scroll table{border-collapse:collapse;min-width:560px;width:100%;font-size:15px}.comparison th,.comparison td,.table-scroll th,.table-scroll td{border-bottom:1px solid var(--border);padding:13px 15px;text-align:left;vertical-align:top}.comparison th,.table-scroll th{background:var(--soft);font-weight:700;color:var(--title)}.comparison tr:last-child td,.table-scroll tr:last-child td{border-bottom:0}.number-list{list-style:none;margin:0;padding:0;counter-reset:counter}.number-list li{counter-increment:counter;position:relative;padding:19px 20px 19px 66px;border-bottom:1px solid var(--border)}.number-list li::before{content:counter(counter);position:absolute;left:10px;top:20px;font-weight:800;font-size:22px;color:#0789a1}.mini-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.mini-grid .surface h3{font-size:19px}.list-lines{padding-left:21px}.list-lines li{margin-bottom:11px}.gallery-grid{display:grid;grid-template-columns:1fr 1fr;gap:22px}.gallery-item{background:#fff;padding:16px;border:1px solid var(--border);border-radius:10px}.gallery-item h3{margin:17px 0 7px}.gallery-item p{font-size:15px;margin-bottom:4px}.rules-index{display:flex;flex-wrap:wrap;gap:10px;padding:20px;background:var(--pale);border-radius:9px}.rules-index a{background:#fff;border:1px solid var(--border);padding:7px 13px;text-decoration:none;border-radius:6px}.faq-stack details{border:1px solid var(--border);background:#fff;border-radius:8px;margin:9px 0;padding:0 18px}.faq-stack summary{cursor:pointer;padding:13px 20px 13px 0;color:var(--title);font-weight:700}.faq-stack details[open] summary{border-bottom:1px solid var(--border)}.faq-stack p{padding-top:12px;margin-bottom:15px}.related-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.related-card{position:relative;display:flex;flex-direction:column;gap:9px;min-height:150px;padding:23px 40px 23px 22px;border:1px solid var(--border);border-radius:9px;background:#fff;text-decoration:none}.related-card strong{color:var(--title);font-size:18px}.related-card span{font-size:14px;color:var(--body)}.related-card b{position:absolute;right:20px;top:19px}.note{border-left:4px solid var(--cyan);background:var(--pale);padding:17px 21px}.site-footer{background:var(--footer);color:#eaf7ff;margin-top:60px;padding-top:42px;font-size:14px}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:48px}.site-footer a{display:block;color:#eaf7ff;margin:5px 0;text-decoration:none}.site-footer a:hover{text-decoration:underline}.footer-name{font-weight:800;font-size:22px}.footer-name small{display:block;font-size:10px;letter-spacing:.15em}.site-footer h2{font-size:17px;color:#fff;margin:0 0 10px}.footer-bottom{display:flex;justify-content:space-between;gap:14px;border-top:1px solid #39617e;padding:17px 0;margin-top:22px;color:#c2d6e5}.mobile-bottom{display:none}.back-top{position:fixed;bottom:26px;right:25px;border:0;background:var(--navy);color:white;border-radius:50%;width:43px;height:43px;cursor:pointer;z-index:10}.back-top[hidden]{display:none}
@media(max-width:1100px){.topic-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.prose-layout{grid-template-columns:minmax(0,1fr) 220px;gap:25px}}@media(max-width:980px){.wrap{width:min(100% - 44px,1180px)}.desktop-nav{display:none}.menu-toggle{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;flex:none;width:40px;height:40px;border:1px solid var(--border);background:#fff;border-radius:7px}.menu-toggle span{width:18px;height:2px;background:var(--navy)}.topbar{height:64px;gap:12px}.brand{margin-right:auto}.brand-logo{max-height:30px;max-width:168px}.brand-type{font-size:20px}.brand-subtitle{display:none}.entry-link{min-height:40px;padding:7px 12px;font-size:13px}.drawer-mask{display:block;position:fixed;inset:0;background:rgba(15,44,64,.45);z-index:40;visibility:hidden;pointer-events:none;opacity:0;transition:opacity .2s,visibility .2s}.mobile-drawer{display:flex;flex-direction:column;position:fixed;top:0;bottom:0;left:0;z-index:41;width:min(86vw,344px);overflow-y:auto;background:#fff;padding:16px 18px 28px;visibility:visible;box-shadow:0 5px 26px #0a30401a}.js .mobile-drawer{transform:translateX(-103%);visibility:hidden;pointer-events:none;transition:transform .24s,visibility .24s}.drawer-open{overflow:hidden}.drawer-open .drawer-mask{visibility:visible;pointer-events:auto;opacity:1}.drawer-open .mobile-drawer{transform:translateX(0);visibility:visible;pointer-events:auto}.drawer-top{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--border);padding-bottom:15px}.drawer-close{border:1px solid var(--border);border-radius:6px;background:#fff;color:var(--navy);font-size:27px;line-height:1;width:40px;height:40px}.drawer-group{font-size:12px;letter-spacing:.08em;font-weight:700;color:var(--muted);margin:18px 0 4px}.mobile-drawer>a{display:block;padding:9px 10px;color:var(--title);font-weight:700;text-decoration:none;border-radius:6px}.mobile-drawer>a.active{background:var(--pale)}.hero{gap:23px}.prose-layout{grid-template-columns:1fr}.sidebar{max-width:780px}.topic-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:760px){.hero,.split,.feature-grid{grid-template-columns:1fr}.hero{padding-top:35px}.hero .media{order:-1}.split.reverse .media{order:0}.column-three,.mini-grid,.related-grid{grid-template-columns:1fr}.feature-side{grid-template-columns:1fr 1fr}.steps{grid-template-columns:1fr 1fr}.footer-grid{grid-template-columns:1fr 1fr}.footer-grid>div:first-child{grid-column:1/-1}.section{margin-block:39px}.page-heading{padding-top:38px}.page-heading h1{font-size:30px}.gallery-grid{grid-template-columns:1fr}.mobile-bottom{display:flex;position:fixed;bottom:0;left:0;right:0;z-index:25;background:#fff;border-top:1px solid var(--border);padding-bottom:env(safe-area-inset-bottom,0px);box-shadow:0 -3px 14px #12365314}.mobile-bottom a{flex:1;text-align:center;padding:10px 4px;font-weight:700;font-size:13px;text-decoration:none;color:var(--navy)}body{padding-bottom:calc(48px + env(safe-area-inset-bottom,0px))}.back-top{bottom:70px}.site-footer{margin-top:42px}}@media(max-width:640px){body{font-size:15px}.wrap{width:calc(100% - 32px)}h1{font-size:29px}h2{font-size:22px}h3{font-size:18px}.hero h1{font-size:29px}.lead{font-size:15px}.hero .media--hero{height:200px}.media--feature{height:180px}.media--card{height:145px}.media--banner{height:150px}.media--mobile{height:290px;max-width:250px}.media--small{height:160px}.topic-grid,.feature-side{grid-template-columns:1fr}.topic-item{padding:18px}.feature-main,.feature-side article,.surface{padding:19px}.quick-inner{gap:8px}.quick-inner span{gap:6px}.section{margin-block:31px}.page-heading{padding-top:28px}.page-heading h1{font-size:27px}.footer-grid{gap:22px}.footer-bottom{flex-wrap:wrap}.steps{grid-template-columns:1fr}.comparison table,.table-scroll table{font-size:14px}.gallery-item{padding:12px}}@media(max-width:980px){html:not(.js) .mobile-drawer{position:static;width:100%;height:auto;max-height:none;box-shadow:none;border-bottom:1px solid var(--border)}html:not(.js) .drawer-close,html:not(.js) .menu-toggle{display:none}}@media(max-height:470px) and (max-width:760px){.mobile-bottom{position:static}body{padding-bottom:0}.back-top{bottom:20px}}@media(min-width:981px){.mobile-drawer,.drawer-mask{display:none!important}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition:none!important;animation:none!important}}