body {
    box-sizing: border-box;
}
.loading { animation: spin 1s linear infinite; }
@keyframes spin { from { transform: rotate(0deg); } to { transform: rotate(360deg); } }
.fade-in { animation: fadeIn 0.3s ease-in; }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
.slide-up { animation: slideUp 0.3s ease-out; }
@keyframes slideUp { from { transform: translateY(20px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }

/* Custom slider styles */
.slider {
    -webkit-appearance: none;
    appearance: none;
    height: 8px;
    border-radius: 5px;
    background: #e5e7eb;
    outline: none;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #3b82f6;
    cursor: pointer;
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #3b82f6;
    cursor: pointer;
    border: none;
}

.grade-display {
    font-weight: bold;
    padding: 4px 8px;
    border-radius: 4px;
    text-align: center;
    min-width: 40px;
}

.card-progress {
    height: 4px;
    background: #e5e7eb;
    border-radius: 2px;
    overflow: hidden;
}

.card-progress-bar {
    height: 100%;
    background: linear-gradient(90deg, #ef4444, #f59e0b, #10b981);
    transition: width 0.3s ease;
}

.page { display: none; }
.page.active { display: block; }

.status-badge { padding: 4px 12px; border-radius: 20px; font-size: 12px; font-weight: 600; }
.status-progress { background: #fef3c7; color: #92400e; }
.status-partial { background: #dbeafe; color: #1e40af; }
.status-complete { background: #d1fae5; color: #065f46; }