*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:#080A0D;color:#C7CDD5;font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif}a{color:#8ED8FF;text-decoration:none}a:hover{text-decoration:underline;color:#B4E6FF}button{font:inherit;cursor:pointer}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #8ED8FF;outline-offset:3px}p{margin:0 0 17px}h1,h2,h3{color:#F5F7FA;line-height:1.4}h1{font-size:34px;letter-spacing:.01em;margin:0 0 20px}h2{font-size:24px;margin:39px 0 19px}h3{font-size:19px;margin:0 0 13px}img{max-width:100%}.container{max-width:1200px;margin:auto;padding:0 24px;min-width:0}.skip-link{position:absolute;top:-100px;left:15px;background:#5C7CFA;color:#080A0D;padding:10px;z-index:100}.skip-link:focus{top:8px}.site-header{position:sticky;top:0;z-index:50;background:rgba(8,10,13,.96);border-bottom:1px solid rgba(255,255,255,.09);backdrop-filter:blur(12px)}.header-inner{max-width:1200px;margin:auto;min-height:68px;padding:0 24px;display:flex;align-items:center;gap:20px;min-width:0}.brand{display:flex;align-items:center;justify-content:flex-start;min-width:105px;max-width:155px;height:42px}.brand img{display:block;max-height:34px;width:auto;height:auto;object-fit:contain}.brand:has(img) .brand-fallback{display:none}.brand-fallback{font-weight:800;font-size:21px;white-space:nowrap;color:#F5F7FA}.brand-fallback span{color:#8ED8FF}.desktop-nav{display:flex;align-items:center;gap:18px;flex:1;min-width:0;white-space:nowrap}.desktop-nav a{color:#C7CDD5;font-size:14px}.desktop-nav a.active,.desktop-nav a[aria-current]{color:#8ED8FF;border-bottom:2px solid #5C7CFA;text-decoration:none}.menu-toggle{background:#171C23;color:#F5F7FA;border:1px solid rgba(255,255,255,.16);border-radius:9px;padding:8px 13px;white-space:nowrap}.entry-button{white-space:nowrap;background:#5C7CFA;color:#fff;border-radius:8px;padding:8px 17px;font-weight:700;font-size:14px}.entry-button:hover{background:#6EA8FF;color:#080A0D;text-decoration:none}.site-menu{position:fixed;top:70px;right:max(24px,calc((100vw - 1200px)/2 + 24px));z-index:80;width:min(740px,calc(100vw - 32px));max-height:min(75vh,700px);overflow:auto;padding:20px 24px;background:#12161C;border:1px solid rgba(255,255,255,.16);border-radius:14px;box-shadow:0 14px 48px #0009}.site-menu[hidden],.menu-overlay[hidden],.back-top[hidden]{display:none!important}.menu-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:10px;color:#F5F7FA}.menu-top button{color:#C7CDD5;background:#171C23;border:1px solid #4A505A;border-radius:8px;padding:5px 11px}.menu-groups{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px 20px}.menu-groups h2{font-size:15px;color:#8ED8FF;margin:8px 0}.menu-groups ul{list-style:none;padding:0;margin:0}.menu-groups li{margin:4px 0}.menu-groups a{font-size:14px;color:#C7CDD5}.all-sections{display:block;border-top:1px solid #333c48;padding-top:12px;margin-top:10px}.menu-overlay{position:fixed;inset:68px 0 0;z-index:70;background:#0009}.breadcrumbs{display:flex;gap:10px;align-items:center;flex-wrap:wrap;font-size:13px;margin-top:26px;color:#9098A3}.breadcrumbs a{color:#9098A3}.page{padding-bottom:72px}.page-intro{max-width:970px;padding-top:40px}.page-intro .eyebrow,.eyebrow{color:#8ED8FF;font-size:13px;letter-spacing:.1em;text-transform:uppercase;font-weight:700}.lead{font-size:17px;color:#C7CDD5;max-width:820px;line-height:1.8}.home-intro{padding-top:54px}.home-intro h1{font-size:38px}.channel-links{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin:27px 0 32px;border-bottom:1px solid rgba(255,255,255,.09);padding-bottom:20px}.channel-links>span{font-size:13px;color:#9098A3}.channel-links a{font-size:13px;background:#171C23;border:1px solid rgba(255,255,255,.09);color:#C7CDD5;border-radius:6px;padding:5px 10px}.article-content{max-width:1030px}.article-content>p,.article-content>ul,.article-content>ol,.article-content>blockquote,.article-content>.note{max-width:820px}.article-content p{line-height:1.83}.article-content h2{border-left:3px solid #5C7CFA;padding-left:13px}.article-content h3{font-size:19px}.reading-list,.steps{margin:15px 0 26px;padding-left:25px}.reading-list li,.steps li{margin-bottom:9px;padding-left:4px}.note{padding:16px 20px;background:#12161C;border-left:3px solid #7775FF;border-radius:0 8px 8px 0;margin:22px 0}.article-content blockquote{margin:32px 0;border-left:3px solid #8ED8FF;padding:15px 24px;background:#0D1015;color:#F5F7FA;font-size:18px}.table-scroll{overflow-x:auto;max-width:100%;margin:22px 0 31px;border:1px solid rgba(255,255,255,.09);border-radius:12px}table{width:100%;border-collapse:collapse;min-width:570px;background:#0D1015;font-size:15px}th,td{text-align:left;vertical-align:top;padding:14px 17px;border-bottom:1px solid rgba(255,255,255,.09)}th{background:#171C23;color:#F5F7FA}tr:last-child td{border-bottom:0}.media-natural{display:grid;place-items:center;min-width:0;padding:8px;background:#0D1015;border-radius:12px}.media-natural>img{display:block;width:auto;height:auto;max-width:100%;max-height:var(--image-max-height,280px);object-fit:contain;object-position:center}.media-missing{display:grid;min-height:110px;place-items:center;color:#9098A3;font-size:13px;text-align:center;padding:15px}.content-figure{margin:25px 0 34px;max-width:820px}.content-figure figcaption,.gallery-grid figcaption{font-size:13px;color:#9098A3;margin-top:9px;line-height:1.6}.split-block{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:23px;margin:24px 0 33px}.split-block>section{min-width:0}.split-block h3{margin-top:10px}.split-block figure{margin:0}.editor-points{display:flex;gap:15px;flex-wrap:wrap;margin:28px 0 24px}.editor-points span{background:#171C23;border:1px solid rgba(255,255,255,.09);padding:7px 16px;border-radius:999px;font-size:14px}.question-grid,.purpose-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin:20px 0 36px}.question,.purpose-grid>section,.essay-panel,.term-columns>section{padding:24px;background:#0D1015;border:1px solid rgba(255,255,255,.09);border-radius:12px;min-width:0}.question h3{color:#F5F7FA}.feature-reading{background:#12161C;border-radius:12px;padding:23px}.short-reads article{border-bottom:1px solid rgba(255,255,255,.09);padding:0 0 12px;margin-bottom:14px}.short-reads h3{margin:0 0 6px}.short-reads p{font-size:14px;margin-bottom:5px}.rule-strip{border-top:2px solid #5C7CFA;padding:12px 5px}.gallery-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin:20px 0 32px}.gallery-grid figure{margin:0;background:#12161C;border:1px solid rgba(255,255,255,.09);border-radius:12px;padding:12px;min-width:0}.gallery-grid .media-natural{min-height:145px}.essay-panels,.term-columns{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:17px;margin:20px 0 33px}.timeline{border-left:2px solid #5C7CFA;margin:22px 0 36px 14px}.timeline section{position:relative;padding:7px 0 25px 34px}.step-no{position:absolute;left:-17px;top:0;background:#5C7CFA;border-radius:50%;color:#fff;width:34px;height:34px;display:grid;place-items:center;font-size:12px;font-weight:700}.timeline h3{margin:0 0 7px}.timeline p{max-width:760px}.jump-index{display:flex;gap:10px;flex-wrap:wrap;padding:12px 0;margin:18px 0}.jump-index a{background:#171C23;padding:7px 12px;border:1px solid rgba(255,255,255,.09);border-radius:6px;font-size:14px}.glossary-term{border-bottom:1px solid rgba(255,255,255,.09);padding:17px 5px;max-width:800px}.glossary-term h3{color:#8ED8FF}.glossary-term p{margin-bottom:3px}.observation-strips>section{display:flex;gap:22px;align-items:flex-start;max-width:830px;border-bottom:1px solid rgba(255,255,255,.09);padding:17px 0}.observation-strips>section>span{font-size:15px;letter-spacing:.08em;color:#8ED8FF;width:70px;flex-shrink:0}.bookmark-list{max-width:850px}.bookmark-list article{display:flex;gap:22px;padding:22px 0;border-bottom:1px solid rgba(255,255,255,.09)}.bookmark-no{font-size:25px;color:#6EA8FF;line-height:1.2}.bookmark-list h3{margin:0 0 7px}.mechanism-chain{display:flex;align-items:stretch;flex-wrap:wrap;gap:10px;margin:25px 0}.mechanism-chain span{flex:1;min-width:130px;background:#171C23;border:1px solid rgba(255,255,255,.16);border-radius:8px;padding:13px;text-align:center;color:#F5F7FA;font-size:14px}.taglinks{display:flex;flex-wrap:wrap;gap:9px}.taglinks a{border:1px solid rgba(255,255,255,.16);padding:5px 9px;border-radius:7px;font-size:13px}.directory-groups{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:15px;margin:16px 0}.directory-groups section{padding:15px 18px;background:#12161C;border-radius:10px;min-width:0}.directory-groups h3{margin:0}.directory-groups ul{margin-bottom:0}.article-content details{max-width:840px;border-bottom:1px solid rgba(255,255,255,.16);padding:14px 4px}.article-content summary{cursor:pointer;color:#F5F7FA;font-size:16px;font-weight:700}.article-content details p{padding:10px 0 0;margin:0}.related{margin-top:45px;padding-top:15px;border-top:1px solid rgba(255,255,255,.09)}.related-list{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:15px}.related-list a{border:1px solid rgba(255,255,255,.09);border-radius:10px;padding:17px;background:#12161C;display:flex;flex-direction:column;gap:5px}.related-list span{color:#9098A3;font-size:13px}.site-footer{background:#050608;border-top:1px solid rgba(255,255,255,.09)}.footer-layout{padding-top:38px;padding-bottom:38px}.footer-identity{display:flex;align-items:center;gap:15px;flex-wrap:wrap}.footer-identity strong{color:#F5F7FA;font-size:20px}.footer-identity span{font-size:12px;color:#9098A3}.footer-identity p{flex-basis:100%;color:#9098A3}.footer-links{display:flex;flex-wrap:wrap;gap:18px;font-size:14px;margin-bottom:22px}.footer-links a{color:#C7CDD5}.disclaimer{font-size:12px;color:#9098A3;max-width:850px}.back-top{position:fixed;right:22px;bottom:25px;background:#5C7CFA;color:#fff;border:none;border-radius:50%;width:45px;height:45px;z-index:10;font-size:22px}@media(max-width:1080px){.desktop-nav{gap:11px}.header-inner{gap:12px}.desktop-nav a{font-size:13px}.brand{min-width:90px}}@media(max-width:980px){.desktop-nav{display:none}.header-inner{justify-content:space-between}.menu-toggle{margin-left:auto}.menu-overlay{inset:0}.site-menu{position:fixed;top:auto;left:0;right:0;bottom:0;width:100%;max-height:85vh;max-height:85dvh;border-radius:16px 16px 0 0;padding:18px 20px calc(20px + env(safe-area-inset-bottom));overflow:auto}.menu-groups{grid-template-columns:repeat(2,minmax(0,1fr))}.menu-toggle{min-height:44px}.entry-button{min-height:44px;display:flex;align-items:center}.container{padding:0 20px}}@media(max-width:650px){body{font-size:15px;line-height:1.8}.container{padding:0 16px}.header-inner{padding:0 16px;min-height:66px;gap:9px}.brand{max-width:96px;min-width:70px}.brand img{max-width:96px;max-height:31px}.brand-fallback{font-size:19px}.menu-toggle{padding:8px 11px;font-size:13px}.entry-button{padding:7px 11px;font-size:13px}.page-intro{padding-top:26px}.home-intro{padding-top:34px}h1,.home-intro h1{font-size:28px;line-height:1.35}h2{font-size:21px;margin:28px 0 15px}h3,.article-content h3{font-size:17px}.lead{font-size:16px}.question-grid,.purpose-grid,.split-block,.essay-panels,.term-columns,.directory-groups{grid-template-columns:1fr;gap:12px}.gallery-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.gallery-grid figure{padding:8px}.gallery-grid .media-natural{min-height:100px}.media-natural>img{max-height:min(var(--image-max-height,210px),210px)}.page-mobile .media-natural>img{max-height:280px}.site-menu{padding-left:16px;padding-right:16px}.menu-groups{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.related-list{grid-template-columns:1fr}.question,.purpose-grid>section,.essay-panel,.term-columns>section{padding:17px}.bookmark-list article{gap:12px}.bookmark-no{font-size:20px}.observation-strips>section{gap:10px}.observation-strips>section>span{width:48px}.channel-links{margin:22px 0}.article-content .content-figure{max-width:100%}.site-menu a{font-size:14px}}@media(max-width:355px){.brand{min-width:65px}.brand-fallback{font-size:17px}.menu-toggle{padding:8px}.entry-button{padding:6px 8px}.gallery-grid{grid-template-columns:1fr}.menu-groups{grid-template-columns:1fr 1fr}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation-duration:.01ms!important;transition-duration:.01ms!important}}