::-webkit-scrollbar { width: 4px; height: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #e2e8f0; border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #cbd5e1; }
.tab-content { display: none; }
.tab-content.active { display: flex; flex-direction: column; }
@media (min-width: 768px) { .tab-content.active { flex-direction: row; } }
.tab-content-full { display: none; }
.tab-content-full.active { display: block; }
/* Mobile lesson drawer */
#lessons-drawer { display: none; position: fixed; inset: 0; z-index: 60; background: white; overflow-y: auto; flex-direction: column; }
#lessons-drawer.is-open { display: flex; }
#drawer-backdrop { display: none; position: fixed; inset: 0; z-index: 59; background: rgba(0,0,0,0.45); }
#drawer-backdrop.is-open { display: block; }
@media (min-width: 768px) { #lessons-drawer { display: flex !important; position: static; width: 18rem; flex-shrink: 0; border-right: 1px solid #e5e7eb; overflow-y: auto; background: white; flex-direction: column; } #drawer-backdrop { display: none !important; } #mobile-modules-btn { display: none !important; } }
/* Mobile PDF chapters drawer */
#pdf-chapters-drawer { display: none; position: fixed; inset: 0; z-index: 60; background: white; overflow-y: auto; flex-direction: column; }
#pdf-chapters-drawer.is-open { display: flex; }
#pdf-drawer-backdrop { display: none; position: fixed; inset: 0; z-index: 59; background: rgba(0,0,0,0.45); }
#pdf-drawer-backdrop.is-open { display: block; }
@media (min-width: 768px) { #pdf-chapters-drawer { display: flex !important; position: static; width: 13rem; flex-shrink: 0; border-right: 1px solid #f3f4f6; overflow-y: auto; background: white; flex-direction: column; height: 100%; } #pdf-drawer-backdrop { display: none !important; } #mobile-pdf-topbar { display: none !important; } }
.lesson-item.active { background: #eff6ff; border-color: #bfdbfe; }
.lesson-item.active .lesson-num { color: #3034ff; }
.lesson-item.active .lesson-title { color: #1e40af; font-weight: 600; }
.lesson-item.completed .check-icon { display: flex; }
.lesson-item.completed .num-icon { display: none; }
.check-icon { display: none; }
.modal-backdrop { backdrop-filter: blur(4px); }
.day-card:hover { border-color: #3034ff; background: #eff6ff; }
.day-card.completed { background: #f0fdf4; border-color: #86efac; }
.day-card.completed .day-num { color: #16a34a; }
@keyframes fadeIn { from { opacity: 0; transform: scale(0.97); } to { opacity: 1; transform: scale(1); } }
.modal-box { animation: fadeIn 0.15s ease; }