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var(--border-subtle);transition:border-color var(--transition-fast), box-shadow var(--transition-fast);border-radius:12px;overflow:hidden}.curriculum-section-card:hover{border-color:var(--border-muted);box-shadow:var(--shadow-sm)}.curriculum-section-header{cursor:pointer;text-align:left;width:100%;transition:background-color var(--transition-fast);background:0 0;border:none;justify-content:space-between;align-items:center;padding:16px 20px;display:flex}.curriculum-section-header:hover{background-color:var(--bg-card-hover)}.curriculum-section-header.is-expanded{border-bottom:1px solid var(--border-subtle)}.section-title-wrap{flex:1;align-items:center;gap:12px;min-width:0;display:flex}.section-index-badge{font-family:var(--font-mono);color:var(--primary);background:var(--primary-glow);border:1px solid #3b82f633;border-radius:6px;flex-shrink:0;padding:3px 8px;font-size:.82rem;font-weight:700}.section-heading-text{color:var(--text-primary);white-space:nowrap;text-overflow:ellipsis;margin:0;font-size:1.05rem;font-weight:700;overflow:hidden}.section-meta-wrap{flex-shrink:0;align-items:center;gap:12px;display:flex}.section-count-badge{color:var(--text-muted);background:var(--bg-app);border:1px solid var(--border-subtle);border-radius:9999px;padding:3px 9px;font-size:.78rem;font-weight:500}.chevron-icon{color:var(--text-muted);transition:transform var(--transition-norm)}.chevron-icon.open{transform:rotate(180deg)}.curriculum-lessons-list{flex-direction:column;display:flex}.curriculum-lesson-item{border-bottom:1px solid var(--border-subtle);cursor:pointer;transition:background-color var(--transition-fast), padding-left var(--transition-fast);justify-content:space-between;align-items:center;padding:12px 20px;display:flex}.curriculum-lesson-item:last-child{border-bottom:none}.curriculum-lesson-item:hover{background-color:var(--bg-card-hover);padding-left:24px}.lesson-left{flex:1;align-items:center;gap:12px;min-width:0;display:flex}.lesson-num{font-family:var(--font-mono);color:var(--text-muted);flex-shrink:0;width:38px;font-size:.78rem}.lesson-title-text{color:var(--text-secondary);white-space:nowrap;text-overflow:ellipsis;transition:color var(--transition-fast);margin:0;font-size:.92rem;font-weight:500;overflow:hidden}.curriculum-lesson-item:hover .lesson-title-text{color:var(--text-primary)}.lesson-right{flex-shrink:0;align-items:center;gap:10px;margin-left:12px;display:flex}.lesson-access-badge{text-transform:uppercase;letter-spacing:.04em;border-radius:6px;align-items:center;gap:4px;padding:2px 8px;font-size:.75rem;font-weight:600;display:inline-flex}.lesson-access-badge.locked{color:var(--text-muted);background:#8b949e1f;border:1px solid #8b949e33}.curriculum-lesson-item:hover .lesson-access-badge.locked{color:var(--primary);background:var(--primary-glow);border-color:#3b82f64d}.lesson-access-badge.accessible{color:var(--diff-easy);background:var(--diff-easy-bg)}.curriculum-bottom-banner{background:linear-gradient(135deg, var(--bg-card) 0%, var(--bg-callout) 100%);border:1px solid var(--border-callout);width:100%;box-shadow:var(--shadow-md);border-radius:16px;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:24px;margin-top:48px;padding:28px 32px;display:flex}.banner-content{flex:1;align-items:center;gap:16px;min-width:280px;display:flex}.banner-icon-wrap{background:var(--primary-glow);width:48px;height:48px;color:var(--primary);border-radius:12px;flex-shrink:0;justify-content:center;align-items:center;display:flex}.banner-text h3{color:var(--text-primary);margin:0 0 4px;font-size:1.15rem;font-weight:700}.banner-text p{color:var(--text-secondary);margin:0;font-size:.88rem;line-height:1.5}.banner-action-btn{background:var(--primary);color:#fff;cursor:pointer;transition:all var(--transition-fast);box-shadow:0 4px 12px var(--primary-glow);white-space:nowrap;border:none;border-radius:10px;padding:12px 24px;font-size:.95rem;font-weight:600}.banner-action-btn:hover{background:var(--primary-hover);transform:translateY(-2px)}@media (width<=640px){.curriculum-hero-title{font-size:1.85rem}.curriculum-hero-desc{font-size:.95rem}.curriculum-stats-row{gap:8px}.curriculum-stat-badge{padding:8px 12px}.curriculum-stat-badge .stat-num{font-size:1.1rem}.curriculum-controls{flex-direction:column;align-items:stretch}.curriculum-toggle-buttons{justify-content:flex-end}.curriculum-section-header{padding:14px 16px}.section-heading-text{font-size:.95rem}.curriculum-lesson-item{padding:10px 14px}.lesson-num{width:32px;font-size:.72rem}.lesson-title-text{font-size:.85rem}.curriculum-bottom-banner{text-align:center;flex-direction:column;align-items:stretch;padding:20px}.banner-content{text-align:center;flex-direction:column}.banner-action-btn{width:100%}.brand-sub-badge{display:none}}