/* ===== Subject Tabs ===== */
.subject-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 2rem;
    padding: 1rem;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.subject-tab {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.subject-tab svg {
    width: 18px;
    height: 18px;
}

.subject-tab:hover {
    background: rgba(167, 139, 250, 0.1);
    border-color: var(--accent-purple);
    color: var(--text-primary);
}

.subject-tab.active {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    border-color: transparent;
    color: white;
}

/* ===== Subject Sections ===== */
.subject-section {
    margin-bottom: 3rem;
}

.subject-section[data-subject]:not(.visible) {
    display: none;
}

.subject-section.visible {
    display: block;
}

.subject-heading {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1.25rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.mega-section {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 2px dashed var(--border-color);
}

.quiz-card.ultimate {
    background: linear-gradient(135deg, 
        rgba(167, 139, 250, 0.2) 0%,
        rgba(234, 179, 8, 0.15) 25%,
        rgba(34, 197, 94, 0.15) 50%,
        rgba(59, 130, 246, 0.15) 75%,
        rgba(244, 114, 182, 0.2) 100%
    );
    border-color: rgba(167, 139, 250, 0.5);
}

.quiz-card.ultimate::before {
    background: linear-gradient(90deg, 
        var(--accent-purple), 
        var(--accent-yellow), 
        var(--accent-green), 
        var(--accent-blue), 
        var(--accent-pink),
        var(--accent-purple)
    );
    background-size: 400% 100%;
    animation: ultimateShimmer 6s linear infinite;
}

@keyframes ultimateShimmer {
    0% { background-position: 400% 0; }
    100% { background-position: -400% 0; }
}

.quiz-card.ultimate:hover {
    border-color: var(--accent-purple);
    box-shadow: 0 0 50px rgba(167, 139, 250, 0.4);
}

/* ===== Quiz Grid ===== */
.quiz-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 1.25rem;
}

.quiz-card {
    position: relative;
    display: flex;
    align-items: center;
    gap: 1.25rem;
    padding: 1.5rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-align: left;
    color: inherit;
    font-family: inherit;
    overflow: hidden;
}

.quiz-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
    opacity: 0;
    transition: opacity 0.3s ease;
}

.quiz-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-glow);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.quiz-card:hover::before {
    opacity: 1;
}

.quiz-card.featured {
    grid-column: 1 / -1;
    background: linear-gradient(135deg, 
        rgba(167, 139, 250, 0.1) 0%,
        rgba(244, 114, 182, 0.1) 100%
    );
    border-color: rgba(167, 139, 250, 0.3);
}

.quiz-card.featured::before {
    opacity: 1;
    background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end), var(--gradient-start));
    background-size: 200% 100%;
    animation: shimmer 3s linear infinite;
}

@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* Mega Quiz Card */
.quiz-card.mega {
    grid-column: 1 / -1;
    background: linear-gradient(135deg, 
        rgba(234, 179, 8, 0.15) 0%,
        rgba(249, 115, 22, 0.15) 50%,
        rgba(239, 68, 68, 0.1) 100%
    );
    border-color: rgba(234, 179, 8, 0.4);
}

.quiz-card.mega::before {
    opacity: 1;
    background: linear-gradient(90deg, var(--accent-yellow), var(--accent-orange), var(--accent-red), var(--accent-orange), var(--accent-yellow));
    background-size: 300% 100%;
    animation: megaShimmer 4s linear infinite;
}

@keyframes megaShimmer {
    0% { background-position: 300% 0; }
    100% { background-position: -300% 0; }
}

.mega-badge {
    background: linear-gradient(135deg, var(--accent-yellow), var(--accent-orange)) !important;
    color: var(--bg-primary) !important;
}

.quiz-card.mega:hover {
    border-color: var(--accent-orange);
    box-shadow: 0 0 40px rgba(249, 115, 22, 0.3);
}

.featured-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    padding: 0.25rem 0.75rem;
    background: var(--accent-purple);
    color: white;
    font-size: 0.625rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    border-radius: var(--radius-sm);
    text-transform: uppercase;
}

.card-icon {
    width: 48px;
    height: 48px;
    flex-shrink: 0;
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
}

.card-icon svg {
    width: 32px;
    height: 32px;
}

.card-content {
    flex: 1;
}

.card-content h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.card-content p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.card-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.75rem;
}

.question-count {
    color: var(--accent);
    font-weight: 500;
}

.difficulty {
    color: var(--text-muted);
    padding: 0.125rem 0.5rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-sm);
}

.card-arrow {
    width: 24px;
    height: 24px;
    color: var(--text-muted);
    transition: transform 0.3s ease, color 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.card-arrow svg {
    width: 20px;
    height: 20px;
}

.quiz-card:hover .card-arrow {
    transform: translateX(6px);
    color: var(--accent);
}