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17px}.hero{border-radius:10px}.hero-text{padding:24px}.hero h1{font-size:28px}.hero p{font-size:11px}.hero-actions{gap:7px}.stats{margin-bottom:25px}.stat-icon{width:30px;height:32px;font-size:14px}.stat{gap:10px;padding:13px}.stat b{font-size:21px}.section-head h2{font-size:16px}.section-head h2 small{display:none}.topic-grid{gap:10px}.topic-card{padding:16px 13px}.topic-card h3{font-size:12px}.topic-card p{font-size:10px;min-height:39px}.topic-glyph{font-size:15px}.topic-count{font-size:9px!important}.panel{padding:20px}.page-title h1{font-size:26px}.problem-row{grid-template-columns:20px 30px minmax(110px,1fr) 42px 20px;padding:12px 11px;gap:6px;font-size:11px}.problem-name{line-height:1.6}.diff{font-size:9px;padding:1px 5px}.filters{gap:7px}.filters input{min-width:100%;width:100%}.filters select{max-width:48%;flex:1;font-size:11px}.filter-meta{margin-left:0;font-size:10px}.detail-title h1{font-size:25px}.detail-actions{gap:6px}.detail-actions .btn{font-size:10px;padding:8px 11px}.detail-grid{gap:16px}.code-line{font-size:10px}.line-no{width:35px;min-width:35px;padding-right:11px}.code-header{padding:13px}.code-header span{font-size:10px}.basics-hero{padding:23px}.basics-hero h1{font-size:25px}.concept-card{padding:20px}.footer{flex-direction:column;gap:5px}.tabs{gap:24px}.next-card{padding:13px;font-size:10px}.skip-link{left:10px}.state-node{font-size:11px;min-width:36px;padding:8px}.top-search .kbd{display:none}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important;animation:none!important}}
.state-graph{width:100%;max-width:330px;max-height:245px;margin:0 auto;display:block;overflow:visible}.state-matrix{display:flex;flex-direction:column;gap:7px}.matrix-row{display:flex;justify-content:center;gap:7px}.matrix-cell{font:13px var(--mono);width:39px;height:36px;display:grid;place-items:center;background:#f5f8ef;border:1px solid #dce4d1;border-radius:5px;color:#80966d}.matrix-cell.active{background:#e8efda;border-color:#9ebd7c;color:#44682e}.state-bars{display:flex;align-items:flex-end;justify-content:center;gap:10px;min-height:147px;width:100%;padding:6px 0}.bar-column{display:flex;flex-direction:column;align-items:center;width:25px;justify-content:flex-end}.bar{background:#dfe8d4;width:100%;border:1px solid #ccd9bc;border-radius:4px 4px 0 0;transition:height .25s}.bar.active{background:#a8bf8b;border-color:#8ba96b}.bar-value{font:10px var(--mono);color:#829773;margin-bottom:7px}.bar-column small{font:8px var(--mono);color:#b2bea5;margin-top:7px}.state-graph+*{margin-top:5px}

/* 简洁版布局 */
:root{--bg:#fbfbf9;--muted:#737b70;--line:#e6e9e1}
body{background:var(--bg)}
.brand{padding:0 13px 25px}.brand strong{font-size:18px;letter-spacing:0}
.nav-item{gap:0}.nav-label{letter-spacing:0;font-size:12px;padding-top:22px}
.topbar{height:70px;background:var(--bg)}.crumb b{font-size:13px}
.side-footer{padding-top:15px}.footer{margin-top:30px;padding-top:17px}
.overview-header{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:30px;padding-bottom:26px;border-bottom:1px solid var(--line)}
.overview-header h1{font-size:30px;letter-spacing:-.8px;margin:0 0 8px;line-height:1.4}
.overview-summary{display:flex;gap:21px;color:#7d8577;font-size:12px}.overview-summary b{font-weight:500}.overview-actions{display:flex;gap:9px}
.section-head h2{font-size:17px}.topic-card{padding:19px 21px;border-radius:6px}.topic-card h3{margin:0;font-size:14px;font-weight:500}.topic-card:hover{transform:none;box-shadow:none}
.mini-progress{margin-top:19px}.mini-progress i{width:77%}.topic-count{color:#89927f!important}
.starter-section{margin-top:30px}.panel,.concept-card,.path-card,.problem-table,.basics-hero{border-radius:6px}
.basics-hero{background:transparent;border:0;padding:0 0 25px;border-bottom:1px solid var(--line);border-radius:0;margin-bottom:25px}
.basics-hero h1{margin:0 0 14px;font-size:29px}.basics-hero p{color:#636f5a;max-width:none;font-size:13px;margin-bottom:0;line-height:2}
.concept-card p,.concept-card li{color:#66745e;font-size:13px}.concept-card pre{font-size:11px}.concept-card h3{font-size:14px}
.page-title h1{margin-top:0;font-size:29px}.page-title p{font-size:12px;margin-top:8px}
.btn:hover{transform:none}.visual-stage{background:white}.visual-top{background:white;padding:16px 22px}.visual-panel{border-radius:6px}
.timeline{padding-bottom:16px}.invariant{background:#f5f7f1}.path-card .phase{font-family:inherit;letter-spacing:0;font-size:12px;color:#87947b}
.path-card h2{font-size:18px}.path-card p{color:#6f7d64}.path-links a{background:#f3f5ef;color:#617452}
.sources h2{font-size:15px;margin:23px 0 6px}.sources h2:first-child{margin-top:0}.sources p{margin:0;max-width:850px;color:#66745e;font-size:13px}
@media(max-width:650px){.topbar{height:60px}.top-search{width:100%}.brand{padding-bottom:24px}.overview-header{align-items:flex-start;flex-direction:column;gap:18px;margin-bottom:25px;padding-bottom:23px}.overview-header h1{font-size:28px}.overview-summary{gap:14px;font-size:11px}.overview-actions .btn{padding:8px 14px}.topic-card{padding:17px 14px}.topic-card h3{font-size:12px}.topic-card .topic-count{font-size:10px!important}.mini-progress{margin-top:18px}.mini-progress i{width:65%}.basics-hero{padding:0 0 21px}.basics-hero h1,.page-title h1{font-size:26px}.concept-card{padding:19px}.sources p{font-size:12px}.footer{margin-top:25px}}
.foundation-page-nav{display:flex;gap:24px;padding:0 0 17px;margin:0 0 24px;border-bottom:1px solid var(--line);font-size:12px;color:#607850;flex-wrap:wrap}.foundation-page-nav a:hover{text-decoration:underline}.foundation-heading{display:flex;align-items:center;justify-content:space-between;gap:15px;margin:25px 0 15px}.foundation-heading h2,.foundation-core-title h2{font-size:18px;margin:0}.foundation-tools{display:flex;gap:7px}.foundation-tools button{font-size:11px}.foundation-prerequisites{display:flex;gap:10px;align-items:center;font-size:12px;margin:0 0 18px;flex-wrap:wrap}.foundation-prerequisites span{color:#929d88;margin-right:3px}.foundation-prerequisites a{background:#f1f4eb;padding:3px 10px;border-radius:4px;color:#647d51}.foundation-find{display:flex;gap:12px;align-items:center;margin-bottom:16px;font-size:12px}.foundation-find input{flex:1;min-width:0;max-width:420px;background:white;border:1px solid #e0e5d8;border-radius:5px;font:12px inherit;padding:8px 11px;color:#4f6541}.foundation-find label{color:#718363}.foundation-find span{color:#9ba68f;font:11px var(--mono);margin-left:auto}.foundation-module-list{border:1px solid var(--line);border-radius:6px;background:white;overflow:hidden}.foundation-module{border-bottom:1px solid var(--line)}.foundation-module:last-child{border:0}.foundation-module[hidden]{display:none}.foundation-module summary{display:flex;list-style:none;gap:16px;align-items:center;padding:20px 24px;cursor:pointer}.foundation-module summary::-webkit-details-marker{display:none}.foundation-module summary::marker{content:''}.foundation-number{font:12px var(--mono);color:#a0ad93;min-width:24px}.foundation-module summary strong{font-size:14px;font-weight:500;color:#3b4a32;display:block}.foundation-summary{display:block;font-size:12px;color:#8a967e;margin-top:4px}.foundation-expand{margin-left:auto;color:#8b9c7b;font:21px var(--mono)}.foundation-module[open] .foundation-expand{transform:rotate(45deg)}.foundation-module[open] summary{background:#fafbf7}.foundation-body{padding:4px 28px 25px 64px;border-top:1px solid #f0f2eb}.foundation-explanation{font-size:14px;color:#4f5e45;line-height:2.1;max-width:960px}.foundation-explanation p{margin:18px 0}.foundation-example{display:grid;grid-template-columns:1.5fr 1fr;margin:23px 0;border:1px solid #e3e8da;border-radius:6px;overflow:hidden;background:#f8faf4}.foundation-example h4{font-size:11px;font-weight:500;margin:0 0 12px;color:#8b9c77}.foundation-code,.foundation-output{padding:17px 20px;min-width:0}.foundation-output{background:#f1f5e9;border-left:1px solid #e2e8d7}.foundation-example pre{font:12px/1.9 var(--mono);white-space:pre;overflow:auto;margin:0;color:#4f693c}.foundation-output pre{white-space:pre-wrap;overflow-wrap:anywhere}.foundation-points{font-size:12px;color:#738465;line-height:2;padding-left:19px;margin:20px 0}.foundation-figure{margin:25px 0;background:white;border:1px solid #e6eadf;border-radius:6px;padding:18px 18px 13px;overflow:hidden}.foundation-figure h4{font-size:13px;margin:0 0 12px;font-weight:500;color:#627a4e}.foundation-diagram-scroll{overflow:auto;scrollbar-width:thin}.foundation-diagram-scroll svg{width:100%;max-height:420px;display:block}.foundation-figure figcaption{border-top:1px solid #f0f2eb;padding-top:12px;font-size:12px;line-height:1.9;color:#7d8e6c}.foundation-check{margin:22px 0 0;padding:17px 18px 3px;border:1px solid #e2e8d8;border-radius:6px;min-width:0}.foundation-check legend{font-size:13px;padding:0 6px;color:#4e673a}.foundation-check>div{display:flex;gap:9px;flex-wrap:wrap}.foundation-check button{padding:7px 12px;border:1px solid #dce4d1;background:white;color:#71875c;font-size:12px;border-radius:5px;text-align:left}.foundation-check button.answer-right{background:#edf5e5;border-color:#8eac74;color:#456731}.foundation-check button.answer-wrong{background:#fff3ed;border-color:#d6a688;color:#a87555}.foundation-feedback{font-size:12px;line-height:1.9;color:#71865c;margin:14px 0}.foundation-feedback:empty{margin-top:0}.foundation-feedback.incorrect{color:#aa7c5b}.foundation-no-result{padding:20px;color:#8c9a7d;font-size:12px}.foundation-core-title{border-top:1px solid var(--line);margin-top:35px;padding-top:27px}.foundation-core-title p{font-size:13px;line-height:2;color:#6e7f61;max-width:950px}.foundation-reference{margin:24px 0 0;display:flex;gap:16px;flex-wrap:wrap;font-size:11px;color:#8c9d7c}.foundation-reference a{text-decoration:underline}.complexity-lab{padding:23px;background:white;border:1px solid var(--line);border-radius:6px;margin:30px 0}.complexity-lab h2{font-size:18px;margin:0 0 15px}.complexity-lab label{font-size:13px;color:#61794e;display:block}.complexity-lab>input{width:100%;accent-color:var(--green);margin:18px 0 12px}.complexity-table-scroll{overflow:auto}.complexity-table{border-collapse:collapse;width:100%;font-size:12px;text-align:left;min-width:520px}.complexity-table th{font-weight:500;color:#748565}.complexity-table th,.complexity-table td{padding:11px 12px;border-bottom:1px solid var(--line)}.complexity-table td{color:#526846}.complexity-table code{font:11px var(--mono)}.complexity-lab>p{font-size:11px;color:#8f9f7f;margin-bottom:0}.complexity-bars{display:grid;gap:13px;margin:25px 0 17px}.complexity-bars>div{display:flex;align-items:center;gap:12px;font:11px var(--mono)}.complexity-bars span{min-width:75px;color:#8c9c7c}.complexity-bars i{display:block;height:12px;background:#c4d4af;border-radius:2px;max-width:75%}.complexity-bars b{font-weight:400;color:#6a8257;min-width:22px}.basics-overview-links{display:flex;align-items:center;gap:13px;margin:20px 0 27px;font-size:12px;flex-wrap:wrap}.basics-overview-links a{color:#607b4d;padding:6px 12px;background:#f1f5e9;border-radius:4px}.basics-overview-links span{color:#849675}.foundation-module summary:focus-visible{outline:2px solid var(--accent);outline-offset:-3px}@media(max-width:940px){.foundation-body{padding-left:25px}.foundation-example{grid-template-columns:1fr}.foundation-output{border-left:0;border-top:1px solid #e2e8d7}}@media(max-width:650px){.foundation-module summary{padding:16px 15px;gap:9px}.foundation-module summary strong{font-size:13px}.foundation-summary{font-size:11px;line-height:1.8}.foundation-body{padding:0 16px 20px}.foundation-explanation{font-size:13px;line-height:2.1}.foundation-explanation p{margin:16px 0}.foundation-number{font-size:10px;min-width:20px}.foundation-example pre{font-size:11px}.foundation-code,.foundation-output{padding:15px}.foundation-figure{padding:14px 12px 11px}.foundation-heading{align-items:flex-start;gap:8px}.foundation-heading h2{font-size:17px}.foundation-tools{gap:3px}.foundation-tools .btn{padding:5px 8px;font-size:10px}.foundation-find{flex-wrap:wrap;gap:8px}.foundation-find label{font-size:11px}.foundation-find input{font-size:11px;padding:8px;max-width:80%}.foundation-find span{font-size:9px;margin-left:0}.foundation-page-nav{gap:20px;font-size:12px}.foundation-prerequisites{font-size:11px;gap:6px}.foundation-points{font-size:11px}.foundation-check{padding:14px 12px 0}.foundation-check legend{font-size:12px}.foundation-check>div{display:grid;grid-template-columns:1fr}.foundation-check button{font-size:11px}.foundation-feedback{font-size:11px}.foundation-figure figcaption{font-size:11px}.complexity-lab{padding:18px}.complexity-table{font-size:11px}.foundation-reference{font-size:10px;gap:10px}.basics-overview-links{font-size:11px;gap:6px}.foundation-core-title{margin-top:26px}}
/* 专题标题与基础讲解使用紧凑间距。 */
.basics-hero{padding-bottom:0;border-bottom:0;margin-bottom:18px}.basics-hero h1{margin-bottom:0}.foundation-page-nav{padding-bottom:14px;margin-bottom:18px}.foundation-heading{margin-top:19px}.foundation-diagram-scroll svg text{font-family:inherit}