:root{--bg:#f6f7f9;--paper:#fff;--ink:#202b32;--muted:#586770;--line:#dce3e6;--accent:#176751;--soft:#eaf3ef;--radius:8px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:90px}body{margin:0;color:var(--ink);background:var(--bg);font-family:"Segoe UI","Malgun Gothic",sans-serif;font-size:16px;line-height:1.85;word-break:keep-all;overflow-wrap:anywhere}a{color:var(--accent);text-underline-offset:4px}button,input,select,textarea{font:inherit}button,.button{display:inline-flex;align-items:center;justify-content:center;border:1px solid #b9c8c3;background:white;color:var(--ink);padding:9px 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button[aria-pressed=true]{background:var(--soft);border-color:var(--accent);color:var(--accent)}.next-prev{display:flex;justify-content:space-between;margin-top:35px;gap:25px;font-size:14px}.plan-list{margin-top:24px}.day{display:grid;grid-template-columns:95px 1fr 70px;gap:24px;padding:24px 0;border-bottom:1px solid var(--line);align-items:start}.day-date{display:flex;flex-direction:column}.day-date strong{font-size:25px;letter-spacing:-1px}.day-date span{font-size:11px;color:var(--muted)}.day h2{font-size:18px;margin-bottom:6px}.day p{font-size:14px;margin-bottom:8px;color:var(--muted)}.day a{font-size:12px}.day .check-label{padding-top:7px}.round{padding-bottom:25px;border-bottom:1px solid var(--line)}.round-title{display:flex;align-items:center;gap:20px}.round-title h2{margin-bottom:8px}.round h3{font-size:19px}.link-row a{font-size:13px;background:var(--soft);padding:3px 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p{font-size:14px;color:var(--muted)}.coverage{display:grid;grid-template-columns:1fr 1fr;gap:12px 30px}.coverage>div{display:flex;justify-content:space-between;gap:20px;font-size:13px;padding:10px 0;border-bottom:1px solid var(--line)}.mockbar{display:flex;align-items:center;flex-wrap:wrap;gap:14px;padding:18px 0;position:sticky;top:72px;background:var(--bg);z-index:5}.mockbar>strong{font-size:27px;font-family:Consolas,monospace;color:var(--accent);min-width:108px}.mockbar>span{font-size:12px;color:var(--muted)}body.mock-active .solution{display:none}#mock-results{background:var(--soft);padding:20px;border-radius:8px}footer{font-size:11px;color:var(--muted);border-top:1px solid var(--line);padding:25px 46px;display:flex;gap:8px;flex-wrap:wrap}footer span{margin-left:auto}#search-panel{max-width:1188px;margin:20px 46px 0;background:white;padding:24px;border:1px solid var(--line);border-radius:8px}#search-panel>label{display:block;font-size:13px;margin-bottom:7px}#global-search{width:100%}#search-results{max-height:360px;overflow-y:auto}#search-results a{display:block;padding:12px 0;border-bottom:1px solid var(--line);text-decoration:none}#search-results small{display:block;color:var(--muted)}.toast{position:fixed;bottom:22px;left:calc(50% + 100px);transform:translateX(-50%);max-width:90vw;background:#203e32;color:white;border-radius:8px;padding:12px 22px;font-size:13px;z-index:50;display:none}.toast.show{display:block}.skip{position:fixed;top:-100px;left:10px;z-index:100;background:white;padding:10px}.skip:focus{top:10px}.mobile-toggle{display:none}.noscript{background:#fff;padding:15px;margin:15px}#dashboard-progress strong{font-size:20px;color:var(--accent)}[hidden]{display:none!important}
@media(min-width:1600px){main{padding-top:55px}}@media(max-width:1200px){.sidebar{width:234px;padding:22px 12px}.workspace{margin-left:234px}main{padding:32px 28px 60px}.topbar{padding:0 28px}.lesson-layout{grid-template-columns:minmax(0,1fr)}.toc{display:none}.stats>div{display:block}.stats span{display:block}.course-grid{gap:0 20px}.start-panel{grid-template-columns:1fr 140px;padding:26px}.split{grid-template-columns:1fr}.coverage{grid-template-columns:1fr}#search-panel{margin:20px 28px 0}}

@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}@media print{body{background:white;font-size:10pt;line-height:1.6}.sidebar,.topbar,.toc,footer,.skip,.toast,.filterbar,.rating,textarea,.answer-label,.check-label,.actions,.next-prev,.mockbar,#search-panel,.mobile-toggle{display:none!important}.workspace{margin:0}main{max-width:none;padding:0}.lesson-layout{display:block}.page-heading{margin-bottom:18px}h1{font-size:25pt;white-space:normal}h2{font-size:16pt;break-after:avoid}h3{break-after:avoid}.concept,.question{break-inside:avoid;padding:16px 0;border-radius:0}.note,.notice{padding:14px}.question{padding:15px}pre{white-space:pre-wrap;font-size:9pt}.course-grid{display:block}.section{margin-top:22px}a{color:inherit}details>div{display:block!important}details::details-content{content-visibility:visible!important;height:auto!important}.stats{margin:0}.start-panel{background:white}.compact{grid-template-columns:150px 1fr}.day{break-inside:avoid}.source{break-inside:avoid}.date-block strong{font-size:50px}@page{margin:16mm}}

/* Mobile-first study controls */
.mobile-close,.mobile-brand,.mobile-dock,.mobile-nav-head,.nav-scrim{display:none}


@media(prefers-reduced-motion:reduce){.sidebar{transition:none}}
.lesson-guide{padding:24px;background:#f0f6f2;border:1px solid var(--line);border-radius:var(--radius);margin:24px 0 32px}
.lesson-guide h2{font-size:21px;margin:12px 0}
.lesson-guide details{margin-top:20px}
.lesson-guide summary,.recall summary{cursor:pointer;padding:10px 0;font-weight:700}
.lesson-guide ul{padding-left:22px;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px 24px}
.lesson-route{display:flex;flex-wrap:wrap;gap:10px;margin-top:18px}
.lesson-route a{padding:10px 14px;background:white;border:1px solid var(--line);border-radius:7px;text-decoration:none;font-weight:700}
.worked-example,.recall{margin:20px 0;padding:18px 20px;border-radius:8px;background:#f6f8fa;border:1px solid var(--line)}
.worked-example h3,.recall h3{font-size:16px;margin:0 0 12px}
.worked-example ol{padding-left:22px;margin:0}
.worked-example li+li{margin-top:10px}
.recall{background:#f2f7f2;border-left:3px solid var(--accent)}
.recall details[open]{border-top:1px solid var(--line);margin-top:12px}
.lesson-table{max-width:100%;overflow-x:auto;margin:22px 0;border:1px solid var(--line);border-radius:8px}
.lesson-table table{border-collapse:collapse;min-width:440px;width:100%;font-size:14px;text-align:left}
.lesson-table caption{text-align:left;padding:14px;font-weight:700;background:#f4f7f5}
.lesson-table th,.lesson-table td{padding:12px 14px;border-bottom:1px solid var(--line);vertical-align:top;overflow-wrap:anywhere}
.lesson-table thead{background:#eef3f0}
.lesson-table tbody th{font-weight:600}
.toc{max-height:calc(100dvh - 120px);overflow-y:auto;overscroll-behavior:contain;padding-right:8px}
.toc .toc-group{display:block;margin:18px 0 8px;color:var(--accent)}

@media print{.lesson-guide{break-inside:avoid}.lesson-table{overflow:visible}.lesson-table table{min-width:0}.recall{background:white}.worked-example,.recall{break-inside:avoid}.toc-group{display:none}}