/* Lesson Drawer Styles */
.lesson-drawer {
    position: fixed;
    top: 0;
    left: 0;
    width: 280px;
    height: 100vh;
    background: var(--bg-surface-solid);
    box-shadow: var(--shadow-main);
    z-index: 1001;
    /* Above normal UI but below overlays */
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    flex-direction: column;
    padding: 20px;
    border-right: 1px solid var(--border-glass);
}

.lesson-drawer.closed {
    transform: translateX(-100%);
}

.drawer-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border-glass);
    padding-bottom: 10px;
}

.drawer-header h3 {
    margin: 0;
    font-size: 1.1rem;
    color: var(--text-main);
}

.icon-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 8px;
    border-radius: 8px;
    transition: background 0.2s;
}

.icon-btn:hover {
    background: var(--bg-item-hover);
    color: var(--text-main);
}

.drawer-actions {
    margin-bottom: 20px;
}

.drawer-btn {
    width: 100%;
    padding: 10px;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.2s;
}

.drawer-btn.primary {
    background: var(--primary);
    color: white;
}

.drawer-btn:hover {
    opacity: 0.9;
    box-shadow: 0 4px 12px rgba(var(--p-h), 90%, 60%, 0.3);
}

.lesson-list-container {
    flex: 1;
    overflow-y: auto;
    /* Custom scrollbar handled by global styles now */
}

/* Chapter & Lesson Items */
.chapter-group {
    margin-bottom: 15px;
}

.chapter-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 5px 0;
    border-bottom: 1px solid var(--border-glass);
    margin-bottom: 8px;
}

.lesson-item {
    padding: 10px;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-main);
    transition: all 0.2s;
    margin-bottom: 5px;
}

.lesson-item:hover {
    background: var(--bg-item-hover);
}

.lesson-item.active {
    background: var(--primary);
    color: white;
    box-shadow: var(--shadow-sm);
}

.lesson-item .status-icon {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.lesson-item.active .status-icon {
    color: rgba(255, 255, 255, 0.8);
}
/* Responsive Adjustments */
@media (max-width: 480px) {
    .lesson-drawer {
        width: 85vw; /* Almost full width */
    }
}