* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #333;
}

.container {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

.screen {
    display: none;
    animation: fadeIn 0.5s ease-in-out;
}

.screen.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Setup Screen */
.setup-card {
    background: white;
    border-radius: 20px;
    padding: 40px;
    text-align: center;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
}

.setup-card h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.setup-card p {
    font-size: 1.1rem;
    color: #666;
    margin-bottom: 30px;
}

.setup-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
    align-items: center;
}

.setup-form label {
    font-weight: 500;
    color: #333;
}

.setup-form select {
    padding: 12px 20px;
    border: 2px solid #e1e8ed;
    border-radius: 10px;
    font-size: 1rem;
    background: white;
    cursor: pointer;
    transition: all 0.3s ease;
}

.setup-form select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

#quiz-mode {
    margin-bottom: 10px;
}

/* Buttons */
.btn {
    padding: 12px 30px;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

.btn-secondary {
    background: #f8f9fa;
    color: #667eea;
    border: 2px solid #667eea;
}

.btn-secondary:hover {
    background: #667eea;
    color: white;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Quiz Screen */
.quiz-header {
    background: white;
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: #e1e8ed;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 15px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-radius: 4px;
    transition: width 0.5s ease;
    width: 0%;
}

.quiz-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

#question-counter {
    font-weight: 500;
    color: #333;
}

.score-display {
    display: flex;
    gap: 20px;
}

.correct-count {
    color: #28a745;
    font-weight: 500;
}

.wrong-count {
    color: #dc3545;
    font-weight: 500;
}

.quiz-card {
    background: white;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.question-container {
    margin-bottom: 30px;
}

#question-text {
    font-size: 1.3rem;
    line-height: 1.6;
    color: #333;
    text-align: center;
}

.options-container {
    display: grid;
    gap: 15px;
    margin-bottom: 30px;
}

.option-btn {
    display: flex;
    align-items: center;
    padding: 15px 20px;
    border: 2px solid #e1e8ed;
    border-radius: 12px;
    background: white;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: left;
    width: 100%;
}

.option-btn:hover {
    border-color: #667eea;
    transform: translateX(5px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.1);
}

.option-letter {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: #f8f9fa;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    color: #667eea;
    margin-right: 15px;
    flex-shrink: 0;
}

.option-text {
    flex: 1;
    font-size: 1rem;
    color: #333;
}

.option-btn.correct {
    background: #d4edda;
    border-color: #28a745;
    color: #155724;
}

.option-btn.correct .option-letter {
    background: #28a745;
    color: white;
}

.option-btn.wrong {
    background: #f8d7da;
    border-color: #dc3545;
    color: #721c24;
}

.option-btn.wrong .option-letter {
    background: #dc3545;
    color: white;
}

.option-btn:disabled {
    cursor: not-allowed;
}

.quiz-controls {
    text-align: center;
}

/* Results Screen */
.results-card {
    background: white;
    border-radius: 20px;
    padding: 40px;
    text-align: center;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.results-card h1 {
    font-size: 2.5rem;
    margin-bottom: 30px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.final-score {
    margin-bottom: 40px;
}

.score-circle {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea, #764ba2);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 0 auto;
    color: white;
}

#score-percentage {
    font-size: 2rem;
    font-weight: 700;
}

.score-label {
    font-size: 0.9rem;
    opacity: 0.9;
}

.score-breakdown {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.score-item {
    padding: 20px;
    border-radius: 12px;
    background: #f8f9fa;
}

.score-item.correct {
    background: #d4edda;
    color: #155724;
}

.score-item.wrong {
    background: #f8d7da;
    color: #721c24;
}

.score-item.total {
    background: #e3f2fd;
    color: #0d47a1;
}

.score-icon {
    font-size: 1.5rem;
    margin-bottom: 10px;
    display: block;
}

.score-text {
    font-weight: 500;
}

.results-actions {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .setup-card,
    .quiz-card,
    .results-card {
        padding: 25px;
    }
    
    .setup-card h1,
    .results-card h1 {
        font-size: 2rem;
    }
    
    #question-text {
        font-size: 1.1rem;
    }
    
    .quiz-info {
        flex-direction: column;
        text-align: center;
    }
    
    .score-display {
        justify-content: center;
    }
    
    .results-actions {
        flex-direction: column;
    }
    
    .score-circle {
        width: 120px;
        height: 120px;
    }
    
    #score-percentage {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .option-btn {
        padding: 12px 15px;
    }
    
    .option-letter {
        width: 35px;
        height: 35px;
        margin-right: 12px;
    }
    
    .option-text {
        font-size: 0.9rem;
    }
}

/* Footer */
.footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-top: 1px solid rgba(102, 126, 234, 0.1);
    padding: 10px 0;
    z-index: 100;
}

.footer-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    padding: 0 20px;
}

.feedback-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: #667eea;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 20px;
    background: rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.feedback-link:hover {
    background: #667eea;
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
}

.feedback-link:active {
    transform: translateY(0);
}

/* Add bottom padding to container to account for footer */
.container {
    padding-bottom: 60px;
}

@media (max-width: 768px) {
    .feedback-link {
        font-size: 0.8rem;
        padding: 6px 12px;
    }
    
    .container {
        padding-bottom: 50px;
    }
}