.knowledge-check {
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 12px;
    margin: 1rem;
}

.quiz-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    font-family: var(--nexus-font-sans);
}

.header-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: #fff;
}

.expand-btn {
    background: none;
    border: none;
    color: #666;
    font-size: 1.2rem;
    cursor: pointer;
}

.question-text {
    font-size: 0.95rem;
    color: #ccc;
    margin-bottom: 1rem;
}

.options-list {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.option-item {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    padding: 0.8rem 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    text-align: left;
    width: 100%;
}

.option-item:hover {
    background: rgba(255, 255, 255, 0.06);
}

.option-item.selected {
    border-color: var(--nexus-neon);
    background: rgba(0, 255, 153, 0.05);
}

.option-letter {
    font-weight: 600;
    color: var(--nexus-neon);
    min-width: 25px;
}

.option-text {
    font-size: 0.9rem;
    color: #fff;
}

.quiz-footer {
    margin-top: 1.5rem;
    display: flex;
    justify-content: center;
}

.submit-btn {
    padding: 0.6rem 2.5rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    color: #888;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.submit-btn:not(:disabled) {
    background: var(--nexus-neon);
    color: #000;
    border-color: var(--nexus-neon);
}

.option-correct {
    border-color: #00ff99 !important;
    background: rgba(0, 255, 153, 0.1) !important;
}

.option-incorrect {
    border-color: #ff4444 !important;
    background: rgba(255, 68, 68, 0.1) !important;
}

.loading-state.shimmer {
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.05), transparent);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    padding: 20px;
    text-align: center;
    color: var(--nexus-neon);
    text-shadow: 0 0 10px var(--nexus-neon);
}

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

.option-revealed-correct {
    border-color: #00ff99 !important;
    background: rgba(0, 255, 153, 0.08) !important;
    box-shadow: 0 0 8px rgba(0, 255, 153, 0.15);
}

.option-faded {
    opacity: 0.45;
}

.submitted-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 2rem 1rem;
    animation: fadeIn 0.4s ease-out;
}

.success-icon-wrapper {
    background: rgba(0, 255, 153, 0.1);
    border: 1px solid rgba(0, 255, 153, 0.3);
    border-radius: 50%;
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    box-shadow: 0 0 20px rgba(0, 255, 153, 0.15);
}

.success-glow {
    color: var(--nexus-neon, #00ff99);
    filter: drop-shadow(0 0 8px var(--nexus-neon, #00ff99));
}

.submitted-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 0.5rem;
    letter-spacing: -0.5px;
}

.submitted-text {
    font-size: 0.9rem;
    color: #888;
    margin-bottom: 2rem;
    line-height: 1.5;
}

.score-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 16px;
    padding: 1.5rem 2.5rem;
    margin-bottom: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    backdrop-filter: blur(10px);
}

.score-main {
    display: flex;
    align-items: baseline;
    gap: 0.2rem;
    margin-bottom: 0.5rem;
}

.score-num {
    font-size: 3rem;
    font-weight: 800;
    color: var(--nexus-neon, #00ff99);
    line-height: 1;
    text-shadow: 0 0 15px rgba(0, 255, 153, 0.3);
}

.score-divider {
    font-size: 1.8rem;
    color: #444;
}

.score-total {
    font-size: 1.8rem;
    font-weight: 600;
    color: #fff;
}

.score-percent {
    font-size: 0.85rem;
    color: #666;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.reset-quiz-btn {
    padding: 0.8rem 3rem;
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 30px;
    color: #fff;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    letter-spacing: 0.5px;
}

.reset-quiz-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: #fff;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.1);
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.empty-quiz-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 2.5rem 1rem;
    animation: fadeIn 0.4s ease-out;
}

.empty-icon-wrapper {
    background: rgba(0, 255, 153, 0.03);
    border: 1px solid rgba(0, 255, 153, 0.15);
    border-radius: 50%;
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    box-shadow: 0 0 30px rgba(0, 255, 153, 0.05);
    transition: all 0.3s ease;
}

.empty-quiz-state:hover .empty-icon-wrapper {
    background: rgba(0, 255, 153, 0.08);
    border-color: rgba(0, 255, 153, 0.4);
    box-shadow: 0 0 35px rgba(0, 255, 153, 0.15);
    transform: scale(1.05);
}

.neon-glow {
    color: var(--nexus-neon, #00ff99);
    filter: drop-shadow(0 0 6px var(--nexus-neon, #00ff99));
}

.empty-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 0.5rem;
    letter-spacing: -0.3px;
}

.empty-text {
    font-size: 0.9rem;
    color: #888;
    margin-bottom: 2rem;
    line-height: 1.5;
    max-width: 280px;
}

.generate-quiz-btn {
    padding: 0.85rem 2rem;
    background: rgba(0, 255, 153, 0.08);
    border: 1px solid var(--nexus-neon, #00ff99);
    border-radius: 30px;
    color: var(--nexus-neon, #00ff99);
    font-size: 0.85rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    letter-spacing: 0.8px;
    text-shadow: 0 0 10px rgba(0, 255, 153, 0.3);
    box-shadow: 0 0 15px rgba(0, 255, 153, 0.1);
}

.generate-quiz-btn:not(:disabled):hover {
    background: var(--nexus-neon, #00ff99);
    color: #000;
    box-shadow: 0 0 25px rgba(0, 255, 153, 0.4);
    transform: translateY(-2px);
    text-shadow: none;
}

.generate-quiz-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    border-color: rgba(255, 255, 255, 0.15);
    background: rgba(255, 255, 255, 0.02);
    color: #666;
    text-shadow: none;
    box-shadow: none;
}