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var(--green-800));color:#fff;border-radius:var(--radius-sm);flex-shrink:0;justify-content:center;align-items:center;width:36px;height:36px;font-size:13px;font-weight:700;display:flex}.lesson-cat-title{color:var(--slate-800);font-size:13px;font-weight:600;line-height:1.4}.lesson-cat-meta{color:var(--color-muted);font-size:11px}.lesson-cat-play{color:var(--green-600);font-size:16px}.course-quickstart{background:linear-gradient(135deg,#dcfce7,#f0fdf4);border:1px solid #bbf7d0;border-radius:14px;flex-wrap:wrap;align-items:center;gap:14px;margin-bottom:24px;padding:16px 20px;display:flex}.section-label{text-transform:uppercase;letter-spacing:.07em;color:var(--green-700);border-bottom:2px solid var(--green-100);align-items:center;gap:6px;margin-bottom:14px;padding-bottom:10px;font-size:11px;font-weight:700;display:flex}.lesson-list{border:1px solid var(--color-border);border-radius:var(--radius-lg);overflow:hidden}.lesson-item{border-bottom:1px solid var(--color-border);cursor:pointer;background:var(--color-surface);align-items:center;gap:14px;padding:14px 18px;transition:background .15s;display:flex}.lesson-item:last-child{border-bottom:none}.lesson-item:hover{background:var(--green-50)}.lesson-item.active{background:var(--green-100);border-left:3px solid var(--green-600)}.lesson-num{background:var(--green-600);color:#fff;border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:30px;height:30px;font-size:12px;font-weight:700;display:flex}.lesson-info h4{color:var(--slate-700);font-size:14px;font-weight:600}.lesson-info p{color:var(--color-muted);font-size:12px}.lesson-play{color:var(--green-600);margin-left:auto;font-size:18px}.player-topbar{border-bottom:1px solid var(--color-border);background:#fff;align-items:center;gap:10px;min-height:44px;padding:10px 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