:root{--ink:#17233a;--muted:#667085;--line:#d7dee8;--paper:#fff;--bg:#f3f6fa;--navy:#183153;--blue:#2764d7;--green:#16794c;--red:#c13b3b;--amber:#a15c00;--radius:18px;font-family:Pretendard,"Noto Sans KR","Malgun Gothic",sans-serif;color:var(--ink);background:var(--bg)}
[hidden]{display:none!important}
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0 14px}.lecture-list{display:grid;gap:8px}.lecture-button{width:100%;padding:13px;text-align:left;border:1px solid transparent;border-radius:14px;background:transparent;color:var(--ink)}.lecture-button:hover,.lecture-button.active{background:#fff;border-color:#bac8dc;box-shadow:0 4px 14px #17345a12}.lecture-button strong{display:block}.lecture-button small{display:flex;justify-content:space-between;margin-top:5px;color:var(--muted)}.priority{color:var(--amber);font-weight:800}.workspace{width:min(1060px,100%);margin:0 auto;padding:24px}.progress-card{display:grid;grid-template-columns:1.5fr repeat(3,1fr) auto;gap:14px;align-items:center;padding:16px 18px;margin-bottom:14px;background:#fff;border:1px solid var(--line);border-radius:var(--radius)}.progress-card div{display:grid;gap:3px}.progress-card span{font-size:.78rem;color:var(--muted)}.progress-card strong{font-size:1.05rem}.question-nav{display:flex;align-items:center;justify-content:space-between;gap:10px;margin:14px 0}.question-dots{display:flex;gap:6px;overflow-x:auto;padding:3px}.dot{min-width:34px;height:34px;border:1px solid var(--line);border-radius:9px;background:#fff}.dot.current{background:var(--navy);color:#fff}.dot.done{border-color:#7c9bd0;background:#edf4ff}.question-card{padding:28px;background:#fff;border:1px solid var(--line);border-radius:22px;box-shadow:0 8px 25px #17345a0d}.question-meta{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:18px}.pill{padding:6px 9px;border-radius:999px;background:#edf2f8;color:#35465f;font-size:.78rem;font-weight:800}.pill.high{background:#fff0d8;color:#854a00}.pill.warn{background:#fff1f1;color:#9f2929}.stem{font-size:1.13rem;line-height:1.75;white-space:pre-wrap}.asset-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:12px;margin:18px 0}.asset-button{padding:0;border:1px solid var(--line);border-radius:14px;overflow:hidden;background:#f8fafc}.asset-button 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#dce4ee;background:#f8fafc;color:#344054;line-height:1.6}.submit-row{display:flex;align-items:center;justify-content:space-between;gap:12px}.result-message{font-weight:900}.result-message.correct-text{color:var(--green)}.result-message.wrong-text{color:var(--red)}.explanation-card{margin-top:20px;padding:20px;border-radius:16px;background:#f6f8fb;border:1px solid #dce3ed}.explanation-card h3{margin:0 0 10px}.explanation-card ol{padding-left:22px;line-height:1.7}.source-list{display:flex;flex-wrap:wrap;gap:8px}.source-list a{color:#174d9d}.related-section,.discussion-section{margin-top:22px;padding:22px;background:#fff;border:1px solid var(--line);border-radius:var(--radius)}.section-heading{display:flex;justify-content:space-between;align-items:center;gap:12px}.section-heading h2{margin:0}.related-list{display:flex;gap:10px;overflow-x:auto;padding:14px 0 4px}.related-card{min-width:245px;padding:14px;border:1px solid var(--line);border-radius:14px;background:#fafcff;text-align:left}.related-card strong{display:block}.related-card small{color:var(--muted)}.status-pill{padding:6px 10px;border-radius:999px;background:#edf2f8;color:var(--muted);font-size:.8rem}.discussion-list{display:grid;gap:9px;margin:16px 0}.discussion{padding:12px 14px;border-radius:12px;background:#f6f8fb}.discussion header{display:flex;justify-content:space-between;gap:8px;margin-bottom:5px;font-size:.82rem}.discussion p{margin:0;white-space:pre-wrap}.empty{color:var(--muted)}.discussion-form{display:grid;grid-template-columns:1fr auto;gap:10px}.discussion-form textarea{min-height:80px;padding:12px;border:1px solid #aab7c8;border-radius:12px;resize:vertical}dialog{width:min(1100px,95vw);max-height:94vh;padding:40px 12px 12px;border:0;border-radius:18px;background:#0d1726}dialog::backdrop{background:#07101bcc}dialog img{display:block;max-width:100%;max-height:82vh;margin:auto}#close-image{position:absolute;right:10px;top:5px;border:0;background:transparent;color:#fff;font-size:2rem}.mobile-only{display:none}@media(max-width:800px){.topbar{height:auto;padding:12px 16px}.layout{display:block}.sidebar{position:sticky;top:0;z-index:4;padding:10px 12px;border-right:0;border-bottom:1px solid var(--line)}.mobile-only{display:inline-block}.lecture-list{display:flex;overflow-x:auto}.lecture-button{min-width:215px;background:#f7f9fc}.workspace{padding:14px}.progress-card{grid-template-columns:repeat(2,1fr)}.progress-card div:first-child{grid-column:1/-1}.progress-card button{grid-column:1/-1}.question-card{padding:20px 16px}.discussion-form{grid-template-columns:1fr}.sidebar.collapsed .lecture-list{display:none}}@media print{.topbar,.sidebar,.question-nav,.discussion-section,.related-section,.submit-row{display:none!important}.layout{display:block}.workspace{width:100%;padding:0}.question-card{box-shadow:none;border:0}}