:root{--paper:#F6FAFC;--white:#fff;--tint:#EAF6FA;--tint2:#EDF4F8;--cyan:#25C8D1;--sky:#25B6E8;--blue:#1787DB;--navy:#174B78;--heading:#183A56;--text:#31485D;--muted:#687D8E;--line:#DCE9F0;--footer:#123653;--content:1180px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:32px}body{margin:0;background:var(--paper);color:var(--text);font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif;overflow-x:hidden}a{color:var(--navy);text-underline-offset:4px}a:hover{color:#087cba}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--sky);outline-offset:3px}h1,h2,h3{color:var(--heading);line-height:1.38;letter-spacing:-.02em}h1{font-size:clamp(32px,3.1vw,42px);margin:0 0 20px}h2{font-size:26px;margin:0 0 19px}h3{font-size:20px;margin:0 0 11px}p{margin:0 0 17px}ul,ol{padding-left:1.4em}li{margin:.35em 0}section{scroll-margin-top:28px}.container{width:min(calc(100% - 56px),var(--content));margin-inline:auto}.site-header{background:#fff;position:relative;z-index:20}.topbar{height:72px;display:flex;align-items:center;gap:24px}.brand{flex:0 0 auto;color:var(--heading);text-decoration:none;display:inline-flex;align-items:center;min-width:0}.brand img{display:block;width:auto;height:auto;max-height:38px;max-width:220px;object-fit:contain}.brand strong{font-size:23px;white-space:nowrap}.brand small{display:block;font-size:10px;letter-spacing:.14em;line-height:1}.topline{margin:auto;color:var(--muted);font-size:13px;letter-spacing:.1em}.entry-btn{display:inline-flex;min-height:42px;align-items:center;justify-content:center;padding:0 22px;text-decoration:none;color:#fff;background:var(--navy);border-radius:8px;font-weight:700;white-space:nowrap}.entry-btn:hover{background:#0b76ad;color:#fff}.desktop-nav{background:var(--navy)}.nav-scroll{display:flex;align-items:center;justify-content:space-between;gap:6px;min-height:48px}.desktop-nav a{color:#eefaff;text-decoration:none;white-space:nowrap;padding:10px 12px;border-bottom:3px solid transparent;font-size:14px}.desktop-nav a:hover,.desktop-nav a[aria-current="page"]{border-color:var(--cyan);background:rgba(255,255,255,.09);color:#fff}.quickbar{background:#eaf6fa;border-bottom:1px solid var(--line)}.quickgroups{display:flex;justify-content:space-between;gap:24px;padding-block:11px;font-size:13px}.quickgroups>div{display:flex;flex-wrap:wrap;gap:10px;align-items:center}.quickgroups b{color:var(--heading);margin-right:5px}.quickgroups 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var(--navy);border-radius:8px;text-decoration:none;font-weight:700}.action--primary{background:var(--navy);color:#fff}.action--primary:hover{background:#0876aa;color:#fff}.media{display:flex;align-items:center;justify-content:center;width:100%;min-width:0;overflow:hidden;background:#eaf6fa;border-radius:14px;border:1px solid #dce9f0}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.media--hero{height:clamp(250px,26vw,330px)}.media--feature{height:250px}.media--card{height:170px}.media--banner{height:220px}.media--mobile{height:350px;max-width:320px}.media--portrait{max-width:340px;margin-inline:auto}.media--wide{height:auto;min-height:115px;max-height:220px}.media--wide img{max-height:220px}.media--placeholder{background:linear-gradient(130deg,#edf7f9,#e1eff5);position:relative}.media--placeholder:after{content:'';width:58px;height:58px;border:2px solid #cfe4ed;border-radius:50%}.topic-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.topic-card{display:flex;flex-direction:column;gap:6px;border:1px solid var(--line);border-radius:12px;background:#fff;padding:21px;text-decoration:none;transition:transform .15s,border-color .15s}.topic-card:hover{transform:translateY(-3px);border-color:#65c2dd}.topic-card strong{font-size:18px;color:var(--heading)}.topic-card span{font-size:14px;line-height:1.7;color:var(--muted)}.topic-card em{font-size:12px;font-style:normal;color:var(--blue);margin-top:auto}.split{display:grid;grid-template-columns:1.5fr 1fr;gap:30px;align-items:start}.split--equal{grid-template-columns:1fr 1fr;align-items:center}.editor-feature{background:#fff;border:1px solid var(--line);border-radius:16px;padding:28px}.editor-note{border-left:3px solid var(--cyan);padding-left:20px;margin-block:15px}.editor-note a{font-weight:700}.link-inline{font-weight:700}.stack{display:grid;gap:17px}.mini-feature{padding:23px;border:1px solid var(--line);border-radius:12px;background:#fff}.mini-feature p:last-child{margin-bottom:0}.feature-copy{max-width:680px}.grid-3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.grid-2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.card{background:#fff;border:1px solid var(--line);border-radius:13px;padding:23px}.card p:last-child{margin-bottom:0}.light-card{background:var(--tint2);border-radius:12px;padding:22px}.steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;counter-reset:step}.step{border-top:3px solid var(--cyan);padding:15px 7px 8px;position:relative}.step strong{display:block}.step:before{counter-increment:step;content:'0' counter(step);color:#1596aa;font-weight:700;font-size:12px}.page-header{padding:43px 0 26px}.page-header h1{font-size:36px}.page-header p{max-width:780px}.article-section{padding-block:30px;border-top:1px solid var(--line)}.article-wrap{max-width:1040px;margin-inline:auto}.article-body{max-width:780px}.article-body p,.article-body li{line-height:1.83}.article-aside-layout{display:grid;grid-template-columns:minmax(0,760px) minmax(0,240px);gap:38px;align-items:start}.aside-box{background:var(--tint);padding:22px;border-radius:13px;position:sticky;top:20px}.aside-box dl{margin:0}.aside-box dt{font-weight:700;color:var(--heading);margin-top:12px}.aside-box dd{margin:0;font-size:14px}.table-wrap{overflow-x:auto;max-width:100%;border:1px solid var(--line);border-radius:12px;margin:22px 0}.data-table{width:100%;border-collapse:collapse;min-width:570px;background:#fff;font-size:15px}.data-table th,.data-table td{padding:14px 17px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}.data-table th{color:var(--heading);background:var(--tint);font-weight:700}.data-table tr:last-child 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@media(max-width:980px){.container{width:min(calc(100% - 44px),var(--content))}.topbar{height:62px;justify-content:space-between;gap:12px}.menu-toggle{display:flex;flex-direction:column;justify-content:center;gap:5px;align-items:center;width:40px;height:40px;padding:0;border:1px solid var(--line);border-radius:7px;background:#fff;flex-shrink:0;cursor:pointer}.menu-toggle span{width:19px;height:2px;background:var(--heading)}.topline,.desktop-nav{display:none}.brand{margin-inline:auto;justify-content:center}.brand img{max-height:30px;max-width:160px}.brand strong{font-size:19px}.entry-btn{height:40px;min-height:40px;padding:0 14px;font-size:13px}.drawer-backdrop{position:fixed;inset:0;background:#0b28466e;z-index:30;visibility:hidden;opacity:0;pointer-events:none;transition:opacity .2s}.mobile-drawer{display:block;position:fixed;z-index:31;inset:0 auto 0 0;width:min(86vw,344px);background:white;overflow-y:auto;transform:translateX(-101%);transition:transform .2s;box-shadow:6px 0 28px #08294420;padding:20px;visibility:hidden;pointer-events:none}.drawer-open{overflow:hidden}.drawer-open .drawer-backdrop{visibility:visible;opacity:1;pointer-events:auto}.drawer-open .mobile-drawer{visibility:visible;pointer-events:auto;transform:translateX(0)}.drawer-top{display:flex;justify-content:space-between;align-items:center;font-weight:700;color:var(--heading);font-size:19px}.drawer-close{font-size:29px;border:0;background:#edf4f8;width:40px;height:40px;border-radius:8px;cursor:pointer;color:var(--heading)}.drawer-group{border-top:1px solid var(--line);margin-top:18px;padding-top:14px}.drawer-group h2{font-size:14px;color:var(--muted);margin:0 0 8px}.drawer-group a{display:block;text-decoration:none;padding:10px 7px;min-height:40px}.quickgroups{flex-wrap:wrap;gap:6px 24px}.topic-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.article-aside-layout{grid-template-columns:minmax(0,1fr) 220px;gap:22px}}
@media(max-width:760px){.container{width:calc(100% - 32px)}.hero-grid,.split,.split--equal,.article-aside-layout,.footer-grid{grid-template-columns:1fr}.hero-grid{gap:23px}.hero{padding:36px 0}.grid-3{grid-template-columns:1fr}.grid-2{grid-template-columns:1fr}.section{padding-block:38px}.page-header{padding:28px 0 16px}.page-header h1{font-size:29px}.article-section{padding-block:22px}.aside-box{position:static}.footer-grid{gap:20px}.footer-bottom{display:block}.footer-bottom span{display:block;margin-top:10px}.steps{grid-template-columns:repeat(2,1fr)}.quickgroups{display:block}.quickgroups>div{margin:5px 0}.bottom-nav{display:flex;position:fixed;bottom:0;left:0;right:0;z-index:19;background:#fff;border-top:1px solid var(--line);padding-bottom:env(safe-area-inset-bottom,0px);box-shadow:0 -3px 16px #174b7814}.bottom-nav a{display:flex;flex:1;min-height:52px;justify-content:center;align-items:center;text-decoration:none;font-size:13px}.bottom-nav a[aria-current="page"]{font-weight:700;color:var(--blue);border-top:3px solid var(--cyan)}body{padding-bottom:calc(52px + env(safe-area-inset-bottom,0px))}.to-top{bottom:70px}.media--hero{height:200px}.media--feature{height:180px}.media--card{height:145px}.media--banner{height:150px}.media--mobile{height:290px;max-width:250px}.media--wide{height:auto;max-height:155px}.media--wide img{max-height:155px}}
@media(max-width:430px){h1{font-size:29px}h2{font-size:22px}h3{font-size:18px}body{font-size:15px}.topic-grid{grid-template-columns:1fr}.brand img{max-width:125px}.brand strong{font-size:16px}.brand small{font-size:8px}.entry-btn{padding-inline:10px}.steps{grid-template-columns:1fr}.hero-grid{gap:18px}.hero{padding:27px 0}.section{padding-block:31px}.card,.editor-feature,.mini-feature{padding:18px}}
@media(max-height:470px) and (max-width:760px){.bottom-nav{position:static}body{padding-bottom:0}.to-top{bottom:20px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important;animation:none!important}}

.nojs-nav{background:#eaf6fa;border-block:1px solid #dce9f0;padding:10px 0}.nojs-nav .container{display:flex;flex-wrap:wrap;gap:8px 19px}.nojs-nav a{font-size:14px;font-weight:700}