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12px;border-radius:7px;color:var(--muted);font-size:11px}.term-card .text-link{font-size:10px}.alphabet{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:20px}.alphabet button{min-width:28px;font-size:10px;padding:5px 7px}.memo-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.memo-card{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:24px;display:flex;gap:16px;align-items:flex-start;color:var(--ink)}.memo-card:hover{background:var(--surface-soft);text-decoration:none}.memo-card>.icon{width:25px;height:25px;color:var(--green)}.memo-card h2{font-size:17px;margin:0 0 7px}.memo-card p{font-size:11px;margin:0;color:var(--muted)}.memo-body{max-width:950px;background:var(--surface);border:1px solid var(--border);padding:30px;border-radius:var(--radius);line-height:1.9}.memo-body table{font-size:12px}.progress-track{height:7px;background:var(--surface-soft);border-radius:8px;overflow:hidden}.progress-track>span{height:100%;display:block;background:var(--green);border-radius:8px}.progress-summary{background:var(--surface);padding:26px;border:1px solid var(--border);border-radius:13px;margin-bottom:22px}.progress-summary p{font-size:12px;color:var(--muted);margin-bottom:18px}.progress-row{display:flex;align-items:center;gap:20px;padding:17px 20px;background:var(--surface);border:1px solid var(--border);border-radius:10px;margin-bottom:9px;font-size:12px}.progress-row>a{flex:1;color:var(--ink)}.progress-row .quiz-score{font-size:10px;color:var(--muted)}.search-tabs{display:flex;gap:8px;margin-bottom:25px;flex-wrap:wrap}.search-result{display:block;padding:20px;background:var(--surface);border:1px solid var(--border);border-radius:10px;margin-bottom:10px;color:var(--ink)}.search-result:hover{background:var(--surface-soft);text-decoration:none}.search-result h2{font-size:17px;margin:7px 0}.search-result p{font-size:12px;color:var(--muted);margin:0}.help-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.help-panel{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:25px;font-size:12px;line-height:1.9}.help-panel h2{font-size:19px}.help-panel ul{padding-left:20px}.help-panel p{color:var(--muted)}.help-panel .button{margin:5px 5px 5px 0;font-size:11px}.danger-link{background:transparent;border:0;color:#a34c3c;font-size:10px;padding:5px 0;margin-top:10px}.backdrop{position:fixed;inset:0;background:#0e211a80;z-index:29}.backdrop[hidden]{display:none}
@media(min-width:1500px){:root{--sidebar:280px}.sidebar{padding-right:27px;padding-left:27px}main{padding-top:44px}.hero h2{font-size:40px}.hero{padding:38px;min-height:280px}.hero-art{right:15px;top:25px;width:280px;height:260px}.course-grid{gap:22px}.card-top{height:110px}}
@media(max-width:1200px){:root{--sidebar:230px}.sidebar{padding-left:14px;padding-right:14px}.topbar{padding:0 28px;gap:18px}main{padding:28px}.hero-grid{grid-template-columns:1fr 240px}.hero{padding:28px}.hero h2{font-size:29px}.hero-art{right:-60px;opacity:.6}.hero-copy{width:80%}.course-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.lesson-layout{grid-template-columns:minmax(0,1fr) 190px;gap:20px}.lesson-body{padding:25px}.footer{margin:0 28px}.stat{padding:15px;gap:10px}.stat-icon{width:33px;height:33px}.stat strong{font-size:21px}}
@media(max-width:950px){.hero-grid{grid-template-columns:1fr}.today-card{display:none}.hero-art{right:10px;opacity:.85}.hero-copy{width:70%}.lesson-layout{grid-template-columns:1fr}.lesson-aside{position:static;display:grid;grid-template-columns:1fr 1fr;gap:15px}.lesson-aside .side-panel{margin:0}.lesson-aside .toc-panel{display:none}.global-search{width:50%}.breadcrumb{font-size:10px}.stats{gap:10px}.stat{padding:12px}.stat-icon{display:none}.dictionary-list,.memo-grid,.help-grid{grid-template-columns:1fr}.course-header h1{font-size:29px}.progress-row{gap:12px;flex-wrap:wrap}.hero h2{font-size:34px}}
@media(max-width:760px){:root{--sidebar:0px}.sidebar{width:260px;transform:translateX(-100%);transition:transform .2s}.sidebar.open{transform:translateX(0)}.menu-toggle{display:grid;flex-shrink:0}.topbar{height:70px;min-height:70px;padding:0 20px;gap:12px}.breadcrumb{display:none}.global-search{width:100%;max-width:none;padding:8px 10px}.global-search input{font-size:11px}.global-search kbd{display:none}.profile{flex-shrink:0}main{padding:25px 20px}.page-heading{margin-bottom:20px}h1{font-size:28px}.date-chip{display:none}.hero{padding:27px;min-height:250px}.hero h2{font-size:33px}.hero-copy{width:75%}.hero-art{right:-70px;opacity:.5}.stats{margin-bottom:28px}.stat strong{font-size:22px}.stat p{font-size:9px}.explore-strip{gap:12px}.explore-tile{padding:16px;gap:10px}.explore-tile>.icon{width:20px}.footer{margin:0 20px;font-size:8px}.footer>span:last-child{display:none}.course-header{padding:23px}.course-header h1{font-size:29px}.course-info{gap:12px}.lesson-body{padding:23px}.course-tabs{gap:20px}.course-grid{gap:14px}.card-body{padding:17px}.card-footer{padding:11px 17px}.card-top{height:85px}.card-body h3{font-size:15px}.toast{left:50%}.filters{gap:7px}.filter-select{margin-left:0}.storage-warning{padding:10px 20px}.memo-body{padding:23px}.lesson-end .button{font-size:11px}}
@media(max-width:480px){main{padding:22px 16px}.topbar{padding:0 16px}.profile{display:none}.hero{padding:25px}.hero h2{font-size:30px}.hero-copy{width:100%}.hero-art{display:none}.hero p{font-size:11px}.stats{gap:7px}.stat{padding:13px 10px;min-width:0}.stat strong{font-size:21px}.stat small{font-size:9px}.stat p{line-height:1.5}.course-grid{grid-template-columns:1fr}.card-top{height:92px}.card-body h3{font-size:17px}.explore-strip{grid-template-columns:1fr}.section-heading h2{font-size:18px}.course-header{padding:20px}.course-header h1{font-size:28px}.lesson-body{padding:20px;font-size:13px}.lesson-body h2{font-size:22px}.lesson-aside{grid-template-columns:1fr}.course-tabs{gap:18px}.course-tabs a{font-size:11px}.progress-row{padding:14px}.progress-row>a{flex-basis:100%}.help-panel{padding:21px}.diagram-node{font-size:10px;padding:9px}.diagram>div{gap:6px}.diagram-arrow{font-size:14px}.course-info{font-size:10px}.page-heading .button{font-size:10px;padding:8px 10px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important;animation:none!important}}
@media print{.sidebar,.topbar,.footer,.course-tabs,.lesson-aside,.toast,.back-link,.lesson-end,.copy-button,.favorite-button{display:none!important}.workspace{margin:0}main{padding:0;max-width:none}.course-header,.lesson-body,.memo-body{border:0;padding:10px 0}.lesson-layout{display:block}:root,:root[data-theme=dark]{--ink:#000;--bg:#fff;--surface:#fff;--muted:#444;--border:#ddd;--green:#174b39;--surface-soft:#f4f4f4}body{background:white}.code-block,.code-top{background:#f4f4f4;color:#111}.code-block pre{white-space:pre-wrap}.lesson-section{break-inside:auto}.callout,.diagram,tr{break-inside:avoid}details.solution>div{display:block!important}details.solution{content-visibility:visible}}
.chip[aria-current="page"]{background:var(--green);border-color:var(--green);color:var(--surface)}
.quiz-option.correct:has(input:checked){border-color:#7eaa6a;background:#e9f2e4;color:#28512e}
.quiz-option.incorrect:has(input:checked){border-color:#c7796d;background:#f8e8e4;color:#73342b}
:root[data-theme=dark] .quiz-option.correct,:root[data-theme=dark] .quiz-option.correct:has(input:checked){border-color:#85ac70;background:#253c29;color:#d3e8cd}
:root[data-theme=dark] .quiz-option.incorrect,:root[data-theme=dark] .quiz-option.incorrect:has(input:checked){border-color:#c88b7a;background:#452c27;color:#f2d2c9}