:root{--bg:#080A0D;--panel:#0D1015;--block:#12161C;--block2:#171C23;--hover:#1B2129;--text:#F5F7FA;--body:#C7CDD5;--muted:#9098A3;--blue:#5C7CFA;--ice:#6EA8FF;--line:rgba(255,255,255,.09);color-scheme:dark}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--body);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;overflow-wrap:anywhere}a{color:inherit;text-decoration:none}a:hover{color:var(--ice)}a:focus-visible,button:focus-visible,summary:focus-visible{outline:2px solid #8ED8FF;outline-offset:4px}h1,h2,h3{margin:0;color:var(--text);line-height:1.4;font-weight:700}p{margin:0 0 17px}.shell{width:min(100% - 48px,1200px);margin-inline:auto}.skip-link{position:absolute;top:-60px;left:12px;z-index:110;background:#fff;color:#000;padding:8px}.skip-link:focus{top:8px}.site-head{background:rgba(8,10,13,.96);border-bottom:1px solid var(--line);position:relative;z-index:30}.head-inner{height:76px;display:flex;align-items:center;gap:21px}.brand{display:flex;align-items:center;flex:0 0 226px;min-width:0;gap:8px}.brand-en{font-size:9px;line-height:1.3;letter-spacing:.06em;color:var(--muted);max-width:85px}.media{margin:0;min-width:0;max-width:100%;background:var(--panel);border:1px solid var(--line);border-radius:13px;overflow:hidden}.media img{display:block;width:100%;height:auto;max-width:100%;object-fit:contain;object-position:center}.media figcaption{padding:10px 13px;font-size:13px;color:var(--muted);border-top:1px solid var(--line);line-height:1.65}.media-placeholder{min-height:130px;background:linear-gradient(135deg,#111720,#0D1015);border-radius:inherit}.brand-logo,.footer-logo{width:auto;border:0;background:none;border-radius:0;flex-shrink:0}.brand-logo img{width:auto;max-width:130px;max-height:36px}.brand-logo .media-placeholder{width:105px;min-height:32px}.desktop-nav{display:flex;align-items:center;gap:clamp(12px,1.4vw,22px);flex:1;justify-content:center;min-width:0}.desktop-nav a{font-size:14px;white-space:nowrap;position:relative;padding:12px 0}.desktop-nav a.active{color:var(--ice)}.desktop-nav a.active:after{content:"";height:2px;background:var(--ice);position:absolute;bottom:6px;left:0;right:0}.entry-link,.pill-link{height:42px;display:inline-flex;align-items:center;justify-content:center;white-space:nowrap;padding:0 20px;border-radius:999px;background:var(--blue);color:#fff;font-size:14px;font-weight:700}.entry-link:hover,.pill-link:hover{background:#7390FF;color:#fff}.menu-toggle{display:none;width:40px;height:40px;border:1px solid var(--line);background:transparent;border-radius:9px;padding:10px;flex-direction:column;justify-content:center;gap:4px}.menu-toggle span{height:2px;width:100%;background:#fff;display:block}.topic-bar{background:#10141A;border-bottom:1px solid var(--line)}.topic-inner{display:flex;align-items:center;gap:29px;min-height:45px;white-space:nowrap}.topic-inner a{font-size:14px;color:var(--body)}.topic-inner a.active{color:var(--ice)}.main-content{padding-top:36px;padding-bottom:70px;min-height:55vh}.breadcrumbs{font-size:13px;color:var(--muted);display:flex;flex-wrap:wrap;gap:9px;margin-bottom:32px}.breadcrumbs a{color:var(--body)}.eyebrow{font-size:12px;letter-spacing:.18em;color:var(--ice);text-transform:uppercase;font-weight:700;margin-bottom:14px}.page-intro{max-width:850px;margin-bottom:42px}.page-intro h1{font-size:34px;letter-spacing:-.02em;margin-bottom:18px}.lead{font-size:17px;line-height:1.85;color:var(--body);max-width:830px}.article-wrap{max-width:820px}.reading-section{padding:0 0 28px;margin:0 0 39px;border-bottom:1px solid var(--line)}.reading-section h2{font-size:26px;margin-bottom:20px}.reading-section h3{font-size:19px;margin:26px 0 12px}.reading-section p{font-size:16px;line-height:1.85}.related{margin-top:43px;padding:24px;background:var(--block);border:1px solid var(--line);border-radius:13px}.related h2{font-size:21px;margin-bottom:18px}.related-links{display:flex;flex-wrap:wrap;gap:11px}.related-links a,.text-link{color:#8ED8FF;border-bottom:1px solid rgba(142,216,255,.4)}.related-links a{padding:4px 0;margin-right:17px}.editor-note{border-left:2px solid var(--ice);padding:15px 22px;background:var(--block);margin:24px 0 36px}.editor-note strong{color:var(--text)}.editor-note p{margin:8px 0 0}.section-head{margin:0 0 24px}.section-head h2{font-size:27px;margin:0 0 8px}.section-head p{color:var(--muted)}.home-section{margin-bottom:56px}.home-hero{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:35px;align-items:center;padding:32px 0 52px;border-bottom:1px solid var(--line)}.home-hero h1{font-size:41px;margin:0 0 24px}.hero-art{height:auto;max-height:310px;display:flex;align-items:center;justify-content:center}.hero-art img{width:auto;max-width:100%;max-height:310px}.hero-art .media-placeholder{width:100%;min-height:260px}.hero-links{display:flex;gap:24px;margin-top:23px}.hero-links a{font-weight:bold;color:#8ED8FF;border-bottom:1px solid var(--ice)}.feature-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.feature{border-top:2px solid #425580;padding:22px;background:var(--block);border-radius:0 0 12px 12px}.feature h3{font-size:21px;margin-bottom:11px}.feature h3 a{color:var(--text)}.feature p{margin:0}.split{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(0,.7fr);gap:38px;align-items:start}.split.equal{grid-template-columns:repeat(2,minmax(0,1fr))}.split.visual{grid-template-columns:minmax(0,1fr) minmax(0,1.1fr);align-items:center}.split.reverse{grid-template-columns:minmax(0,1.2fr) minmax(0,.8fr)}.split>*{min-width:0}.indexed-list{list-style:none;margin:0;padding:0;counter-reset:item}.indexed-list li{padding:17px 0;border-bottom:1px solid var(--line);counter-increment:item}.indexed-list li:before{content:counter(item,decimal-leading-zero);font-size:12px;letter-spacing:.08em;margin-right:15px;color:var(--ice)}.indexed-list p{margin:9px 0 0;font-size:14px}.picture-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:17px}.picture-grid .media img{max-height:180px;width:auto;max-width:100%;margin:auto}.picture-grid .media{display:flex;flex-direction:column;justify-content:center}.picture-grid .media-placeholder{min-height:165px}.visual-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.visual-grid .media img{width:auto;max-width:100%;max-height:230px;margin:auto}.visual-grid .media-placeholder{min-height:190px}.device-art{width:min(100%,270px);margin-inline:auto}.device-art img{max-height:340px;width:auto;margin:auto}.device-art .media-placeholder{min-height:260px}.compact-table{border-collapse:collapse;width:100%;font-size:15px;margin:20px 0 30px}.compact-table th,.compact-table td{border-bottom:1px solid var(--line);text-align:left;padding:13px;vertical-align:top}.compact-table th{color:var(--text);background:var(--block)}.learning-steps{padding:0;list-style:none;counter-reset:lesson}.learning-steps li{counter-increment:lesson;margin:0 0 24px;padding:0 0 22px 46px;position:relative;border-bottom:1px solid var(--line)}.learning-steps li:before{content:counter(lesson,decimal-leading-zero);position:absolute;left:0;top:0;color:var(--ice);font-size:17px;font-weight:700}.learning-steps h2{font-size:20px;margin-bottom:11px}.learning-steps p{margin:0}.topic-index{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:17px}.topic-index article{border:1px solid var(--line);border-radius:12px;padding:20px;background:var(--block)}.topic-index h2{font-size:20px;margin-bottom:10px}.topic-index p{font-size:15px}.topic-index .related-links{gap:5px}.news-items article{border-bottom:1px solid var(--line);padding:19px 0}.news-items h2{font-size:21px;margin-bottom:9px}.news-items p{margin:0 0 8px}.image-story{display:grid;grid-template-columns:minmax(0,220px) minmax(0,1fr);gap:22px;align-items:center;margin:32px 0}.image-story .media img{max-height:210px;width:auto;margin:auto}.gallery-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:19px}.gallery-grid .media img{width:auto;margin:auto;max-height:260px}.gallery-grid .media-placeholder{min-height:190px}details{border-bottom:1px solid var(--line);padding:17px 0}summary{cursor:pointer;color:var(--text);font-size:18px;font-weight:bold}details p{padding:15px 0 0;margin:0}.site-footer{background:#050608;border-top:1px solid var(--line);padding-top:45px}.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:55px;padding-bottom:32px}.footer-grid h2{font-size:17px;margin:0 0 18px}.footer-grid p{font-size:14px;color:var(--muted)}.footer-logo img{max-height:34px;width:auto;max-width:130px}.footer-logo .media-placeholder{width:110px;min-height:32px}.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px 15px}.footer-links a{font-size:13px;color:var(--muted)}.footer-links a:hover{color:var(--ice)}.footer-bottom{border-top:1px solid var(--line);padding:18px 0 25px;display:flex;gap:24px;justify-content:space-between;font-size:12px;color:var(--muted)}.site-drawer{position:fixed;z-index:101;top:0;bottom:0;left:0;width:min(86vw,390px);background:var(--panel);border-right:1px solid var(--line);visibility:hidden;pointer-events:none;transform:translateX(-105%);transition:transform .24s ease,visibility .24s;display:flex;flex-direction:column}.drawer-backdrop{position:fixed;inset:0;background:rgba(0,0,0,.76);z-index:100;visibility:hidden;opacity:0;pointer-events:none;transition:opacity .24s,visibility .24s}.drawer-open .site-drawer{visibility:visible;pointer-events:auto;transform:translateX(0)}.drawer-open .drawer-backdrop{visibility:visible;opacity:1;pointer-events:auto}.drawer-top{display:flex;align-items:center;justify-content:space-between;padding:15px 20px;border-bottom:1px solid var(--line)}.drawer-close{background:none;border:1px solid var(--line);color:#fff;font-size:29px;width:40px;height:40px;border-radius:8px;cursor:pointer}.drawer-scroll{overflow-y:auto;padding:8px 21px 32px}.drawer-group{border-bottom:1px solid var(--line);padding:15px 0}.drawer-group h2{font-size:13px;color:var(--ice);margin-bottom:12px}.drawer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:7px 15px}.drawer-links a{padding:5px 0;font-size:14px}.back-to-top{position:fixed;right:22px;bottom:23px;background:var(--blue);border:0;color:#fff;border-radius:50%;width:43px;height:43px;cursor:pointer;opacity:0;pointer-events:none;transition:opacity .2s;z-index:20}.back-to-top.visible{opacity:1;pointer-events:auto}@media(max-width:1100px){.brand{flex-basis:175px}.brand-en{display:none}.desktop-nav{gap:13px}.desktop-nav a{font-size:13px}}@media(max-width:979px){.shell{width:min(100% - 40px,1200px)}.head-inner{height:64px;justify-content:space-between;position:relative}.menu-toggle{display:flex}.brand{position:absolute;left:50%;transform:translateX(-50%);width:auto;flex-basis:auto;justify-content:center}.brand-logo img{max-height:28px;max-width:110px}.brand-logo .media-placeholder{width:85px;min-height:27px}.desktop-nav{display:none}.entry-link{height:40px;padding:0 14px}.topic-inner{overflow-x:auto;scrollbar-width:none;gap:24px;min-height:44px}.topic-inner::-webkit-scrollbar{display:none}.topic-inner a{font-size:13px}.split{gap:25px}.footer-grid{gap:30px}}@media(max-width:767px){.shell{width:calc(100% - 32px)}.main-content{padding-top:24px;padding-bottom:44px}.page-intro{margin-bottom:33px}.page-intro h1{font-size:26px}.lead{font-size:15px}.reading-section h2,.section-head h2{font-size:22px}.reading-section p{font-size:15px}.home-hero{grid-template-columns:1fr;padding:4px 0 35px;gap:20px}.home-hero .hero-art{grid-row:1;max-height:205px}.home-hero .hero-art img{max-height:205px}.home-hero .hero-art .media-placeholder{min-height:175px}.home-hero h1{font-size:30px}.home-section{margin-bottom:35px}.split,.split.equal,.split.visual,.split.reverse{grid-template-columns:1fr;gap:21px}.feature-grid,.topic-index{grid-template-columns:1fr}.picture-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.picture-grid .media img{max-height:155px}.visual-grid .media img{max-height:185px}.image-story{grid-template-columns:1fr}.image-story .media{max-width:300px}.gallery-grid{grid-template-columns:1fr}.gallery-grid .media img{max-height:220px}.footer-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:28px}.footer-about{grid-column:1/-1}.footer-bottom{flex-direction:column;gap:9px}.device-art{max-width:220px}.related{padding:17px}.drawer-links a{font-size:14px}}@media(max-width:359px){.entry-link{padding:0 11px;font-size:12px}.brand-logo img{max-width:91px}.picture-grid,.visual-grid{grid-template-columns:1fr}.head-inner{gap:6px}.menu-toggle{width:40px;flex:0 0 40px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}
