:root{--bg:#F6F8F8;--paper:#fff;--quiet:#EAF0F2;--navy:#122E3B;--navy2:#1A4050;--teal:#168E96;--link:#226D9D;--title:#193946;--text:#374D58;--muted:#647981;--line:#D9E3E6;--footer:#0C2632;font-family:Arial,'PingFang SC','Microsoft YaHei',sans-serif;color:var(--text);background:var(--bg)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:98px}body{margin:0;font-size:16.5px;line-height:1.8}a{color:var(--link);text-underline-offset:3px}a:hover{color:var(--teal)}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #28bac1;outline-offset:4px}img{max-width:100%}h1,h2,h3{color:var(--title);line-height:1.35}h1{font-size:clamp(34px,3.2vw,42px);letter-spacing:-.025em;margin:0 0 22px}h2{font-size:clamp(24px,2.25vw,28px);margin:0 0 20px}h3{font-size:20px;margin:0 0 12px}p{margin:0 0 18px}ul,ol{padding-left:1.3em}li{margin-bottom:9px}small,.muted{color:var(--muted)}.container{width:min(100% - 56px,1220px);margin-inline:auto}.page-content{padding-bottom:75px;min-width:0}.skip-link{position:absolute;top:-120px;left:12px;z-index:100;background:white;padding:8px 16px}.skip-link:focus{top:8px}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.site-header{background:var(--navy);color:white;position:relative;z-index:10}.header-inner{height:76px;display:flex;align-items:center;gap:clamp(12px,1.5vw,22px)}.brand{display:flex;align-items:center;gap:9px;min-width:0;flex:none;text-decoration:none;color:white}.brand img{display:block;width:auto;height:auto;max-height:38px;max-width:150px;object-fit:contain}.brand-text{color:white;white-space:nowrap;font-size:21px}.brand-sub{font-size:9px;letter-spacing:.1em;line-height:1.25;color:#b5d0d6;max-width:67px}.desktop-nav{display:flex;align-items:center;justify-content:center;flex:1;gap:clamp(6px,.8vw,15px);min-width:0}.desktop-nav a{font-size:clamp(12px,.91vw,14px);font-weight:600;white-space:nowrap;color:#e0ebed;text-decoration:none;position:relative;padding:23px 1px}.desktop-nav a::after{content:'';height:2px;background:#53d1ce;position:absolute;bottom:15px;left:0;right:0;transform:scaleX(0);transition:transform .18s}.desktop-nav a:hover::after,.desktop-nav a.is-current::after{transform:scaleX(1)}.desktop-nav a.is-current{font-weight:800;color:white}.entry-link{flex:none;white-space:nowrap;border:1px solid #8dc0c5;border-radius:8px;padding:5px 11px;color:white;text-decoration:none;font-weight:700;font-size:13px}.entry-link:hover{background:var(--navy2);color:white}.menu-toggle,.mobile-nav{display:none}.breadcrumb{padding-block:17px 22px;color:var(--muted);font-size:13px}.breadcrumb a{color:var(--muted)}.breadcrumb span{margin-left:6px}
.hero,.split,.feature-grid,.two-col,.three-col,.sports-frame,.guide-columns,.editorial-feature{display:grid;gap:clamp(22px,3.2vw,44px);min-width:0}.hero{grid-template-columns:minmax(0,1.35fr) minmax(0,1fr);align-items:center;padding:30px 0 35px}.hero .lead{font-size:18px}.hero h1{max-width:710px}.hero-actions,.link-row{display:flex;gap:13px;flex-wrap:wrap;margin-top:19px}.text-action{display:inline-flex;border:1px solid var(--line);border-radius:8px;padding:7px 15px;background:white;font-weight:700;text-decoration:none}.text-action.primary{background:var(--navy2);color:white;border-color:var(--navy2)}.text-action:hover{border-color:var(--teal)}.section{margin-top:56px}.section-header{max-width:780px;margin-bottom:24px}.eyebrow{text-transform:uppercase;letter-spacing:.11em;font-size:12px;color:var(--teal);font-weight:800;margin-bottom:10px}.panel{background:var(--paper);border:1px solid var(--line);border-radius:12px;padding:clamp(19px,2.1vw,26px)}.soft{background:var(--quiet);border-radius:12px;padding:24px}.split{grid-template-columns:minmax(0,2fr) minmax(0,1fr)}.feature-grid{grid-template-columns:repeat(2,minmax(0,1fr));align-items:center}.two-col{grid-template-columns:repeat(2,minmax(0,1fr))}.three-col{grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.topic-groups{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:0;border-block:1px solid var(--line)}.topic-group{padding:20px 22px;border-right:1px solid var(--line);min-width:0}.topic-group:first-child{padding-left:0}.topic-group:last-child{border:0}.topic-item + .topic-item{border-top:1px solid var(--line);padding-top:15px;margin-top:15px}.topic-index{font-size:12px;color:var(--teal);font-weight:800;letter-spacing:.07em}.topic-item h3{font-size:19px;margin:4px 0 8px}.topic-item p{font-size:14.5px;line-height:1.72;margin-bottom:7px}.steps{counter-reset:step;list-style:none;padding:0;display:grid;gap:12px}.steps li{counter-increment:step;position:relative;padding:12px 12px 12px 53px;border-left:2px solid var(--teal);background:white;min-width:0}.steps li::before{content:counter(step,decimal-leading-zero);position:absolute;left:11px;top:12px;font-size:17px;font-weight:800;color:var(--teal)}.steps li strong{display:block;color:var(--title)}.reading-path{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.reading-path a{display:block;text-decoration:none;padding:19px;border-top:3px solid var(--teal);background:white}.reading-path strong{display:block;color:var(--title)}.reading-path span{display:block;color:var(--muted);font-size:14px;margin-top:8px}.article-intro{max-width:790px;padding:21px 0 26px}.article-intro p{font-size:18px}.article{max-width:780px}.article p{line-height:1.84}.article h2,.full-article h2{margin-top:34px}.full-article{max-width:1040px;margin-inline:auto}.article-section{margin-top:43px;scroll-margin-top:100px}.article-section>h2{margin-bottom:18px}.subtle-rule{border:0;border-top:1px solid var(--line);margin:35px 0}.contents{display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin:20px 0 29px}.contents a{border:1px solid var(--line);border-radius:5px;padding:4px 12px;background:white;text-decoration:none;font-size:14px}.contents a:hover{border-color:var(--teal)}.contents-label{font-weight:800;color:var(--title);font-size:14px}.sports-frame{grid-template-columns:205px minmax(0,1fr);gap:30px}.side-index{align-self:start;position:sticky;top:22px;border-left:2px solid var(--line);padding-left:15px}.side-index a{display:block;margin:8px 0;text-decoration:none}.comparison{width:100%;border-collapse:collapse;text-align:left;min-width:610px}.comparison caption{text-align:left;color:var(--muted);font-size:13px;margin-bottom:8px}.comparison th,.comparison td{border-bottom:1px solid var(--line);padding:13px 15px;vertical-align:top}.comparison th{background:var(--quiet);color:var(--title)}.table-scroll{overflow-x:auto;max-width:100%;border:1px solid var(--line);border-radius:8px;margin:20px 0 28px}.notice{padding:18px 23px;background:var(--quiet);border-left:3px solid var(--teal)}.deep-band{background:var(--navy2);color:#eaf5f5;padding:29px;border-radius:9px}.deep-band h2,.deep-band h3{color:white}.deep-band p{margin-bottom:10px}.quote{margin:20px 0;padding:10px 25px;border-left:4px solid var(--teal);font-size:19px;color:var(--title);background:var(--quiet)}.kicker{color:var(--teal);font-size:13px;font-weight:800}.definition-list{display:grid;grid-template-columns:160px 1fr;gap:10px 22px}.definition-list dt{font-weight:800;color:var(--title)}.definition-list dd{margin:0 0 10px}.faq{margin-top:35px}.faq details{border-bottom:1px solid var(--line);padding:10px 0}.faq summary{font-weight:750;color:var(--title);cursor:pointer;padding:9px 30px 9px 0}.faq details p{padding:4px 28px 7px 0;margin:0}.related{margin-top:55px;border-top:2px solid var(--line);padding-top:22px}.related h2{font-size:21px}.related ul{list-style:none;padding:0;display:flex;flex-wrap:wrap;gap:12px}.related a{display:block;background:var(--quiet);text-decoration:none;padding:8px 14px;border-radius:6px}.related li{margin:0}.guide-columns{grid-template-columns:minmax(0,1.6fr) minmax(0,1fr);align-items:start}.compact-section{padding-bottom:18px;border-bottom:1px solid var(--line)}.compact-section + .compact-section{margin-top:22px}.guide-panel{background:var(--quiet);border-radius:12px;padding:25px}.guide-panel h2{font-size:22px}.chapter-number{font-size:13px;font-weight:800;color:var(--teal);letter-spacing:.1em}.image-holder{display:flex;flex-direction:column;align-items:center;justify-content:center;max-width:100%;min-width:0;width:100%;margin:0;padding:8px;background:var(--quiet);border-radius:12px;--image-limit:180px}.image-holder img{display:block;width:auto;height:auto;max-width:100%;max-height:var(--image-limit);object-fit:contain;object-position:center}.image-holder figcaption{font-size:12px;color:var(--muted);padding:7px 3px 0;text-align:center}.image-holder--hero{--image-limit:290px}.image-holder--feature{--image-limit:240px}.image-holder--inline{--image-limit:180px}.image-holder--rules{--image-limit:210px}.image-holder--wide{--image-limit:190px}.image-holder--portrait{--image-limit:330px;max-width:310px;margin-inline:auto}.image-missing{font-size:13px;padding:10px 14px;background:var(--quiet);border:1px dashed var(--line);border-radius:6px;color:var(--muted)}.feature-image{max-width:550px;margin-inline:auto}.football-photo .image-holder{--image-limit:240px}.esports-photo .image-holder{--image-limit:245px}.callout-stack{display:grid;gap:15px}.callout-stack div{border-top:2px solid var(--line);padding-top:13px}.site-footer{background:var(--footer);color:#cee0e5;padding:40px 0 18px}.footer-layout{display:grid;grid-template-columns:1.25fr 1fr;gap:70px}.footer-brand{font-size:23px;font-weight:800;color:white}.footer-brand span{font-size:11px;letter-spacing:.12em;color:#b9d6de;margin-left:10px}.footer-note{font-size:13px;color:#adc3ca}.site-footer h2{font-size:16px;color:#fff;margin:0 0 12px}.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:7px 16px}.footer-links a,.footer-bottom a{color:#c5e6e9}.footer-bottom{border-top:1px solid #36505b;margin-top:25px;padding-top:15px;font-size:13px;color:#b6cbd0}
@media(max-width:1190px){.brand-sub{display:none}.desktop-nav{gap:8px}.desktop-nav a{font-size:12px}.entry-link{padding:5px 9px}}
@media(max-width:980px){.container{width:min(100% - 44px,1220px)}.header-inner{height:64px;justify-content:space-between}.brand{margin:auto}.brand-sub{display:block}.brand img{max-height:30px;max-width:135px}.desktop-nav{display:none}.menu-toggle{display:flex;align-items:center;justify-content:center;flex:none;border:1px solid #809aa3;border-radius:6px;width:42px;height:42px;font-size:23px;background:transparent;color:white;cursor:pointer}.menu-toggle[hidden]{display:none}.mobile-nav{display:block;border-top:1px solid #31515e}.mobile-nav:not([open]) .mobile-nav-inner{display:none}.mobile-nav-summary{font-size:13px;padding:5px 22px;cursor:pointer;color:white}.mobile-nav-summary[hidden]{display:none}.mobile-nav-inner{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;padding-block:18px 22px}.mobile-group h2{color:#9edbdd;font-size:13px;margin-bottom:8px}.mobile-group a{display:block;color:white;text-decoration:none;padding:7px 2px}.mobile-group a.is-current{border-bottom:2px solid #71d7d2;font-weight:800}.menu-close{grid-column:1/-1;justify-self:start;background:transparent;color:white;border:1px solid #8bacb5;border-radius:6px;padding:6px 13px;cursor:pointer}.menu-close[hidden]{display:none}.topic-groups{grid-template-columns:1fr}.topic-group,.topic-group:first-child{padding:17px 0;border-right:0;border-bottom:1px solid var(--line);display:grid;grid-template-columns:1fr 1fr;gap:25px}.topic-group:last-child{border:0}.topic-item + .topic-item{border-top:0;margin:0;padding:0}.reading-path{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:760px){body{font-size:16px}.hero,.split,.feature-grid,.two-col,.sports-frame,.guide-columns,.editorial-feature,.footer-layout{grid-template-columns:1fr}.hero{padding-top:12px}.hero .lead,.article-intro p{font-size:16px}.sports-frame{gap:10px}.side-index{position:static;display:flex;flex-wrap:wrap;gap:8px;border-left:0;border-bottom:1px solid var(--line);padding:0 0 12px}.side-index a{margin:0;padding:3px}.three-col{grid-template-columns:1fr}.section{margin-top:37px}.footer-layout{gap:18px}.definition-list{grid-template-columns:1fr;gap:0}.definition-list dd{margin-bottom:18px}}
@media(max-width:640px){.container{width:min(100% - 32px,1220px)}body{font-size:15.5px;line-height:1.78}h1{font-size:clamp(26px,7.5vw,30px)}h2{font-size:clamp(20px,5.4vw,23px)}h3{font-size:18px}.brand-sub{font-size:8px}.entry-link{font-size:12px;padding:5px 7px}.header-inner{gap:5px}.brand img{max-width:110px}.mobile-nav-inner{grid-template-columns:1fr;gap:15px}.menu-close{grid-column:auto}.topic-group,.topic-group:first-child{grid-template-columns:1fr;gap:12px}.topic-item + .topic-item{border-top:1px solid var(--line);padding-top:12px}.reading-path{grid-template-columns:1fr}.image-holder--hero{--image-limit:195px}.image-holder--feature,.football-photo .image-holder{--image-limit:180px}.esports-photo .image-holder{--image-limit:175px}.image-holder--inline{--image-limit:140px}.image-holder--rules{--image-limit:165px}.image-holder--wide{--image-limit:125px}.image-holder--portrait{--image-limit:275px;max-width:240px}.section{margin-top:34px}.panel,.soft{padding:17px}.footer-links{grid-template-columns:repeat(2,minmax(0,1fr))}.hero-actions{gap:7px}.text-action{padding:6px 10px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition:none!important;animation:none!important}}
