/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #333;
    line-height: 1.6;
    min-height: 100vh;
}

/* App Container */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 2rem 0;
    text-align: center;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

.header-content h1 {
    color: #4a5568;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.header-content h1 i {
    color: #667eea;
    margin-right: 0.5rem;
}

.header-content p {
    color: #718096;
    font-size: 1.1rem;
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

/* Card Styles */
.card {
    background: white;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    margin-bottom: 2rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.card-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1.5rem 2rem;
}

.card-header h2 {
    font-size: 1.5rem;
    font-weight: 600;
}

.card-header h2 i {
    margin-right: 0.5rem;
}

.card-body {
    padding: 2rem;
}

/* Form Styles */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-weight: 600;
    color: #4a5568;
    margin-bottom: 0.5rem;
    font-size: 1rem;
}

.form-group label i {
    margin-right: 0.5rem;
    color: #667eea;
}

.input-group {
    display: flex;
    gap: 0.5rem;
}

.input-group input {
    flex: 1;
}

.form-text {
    color: #718096;
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

/* Input Styles */
input[type="password"],
input[type="file"] {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid #e2e8f0;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

input[type="password"]:focus,
input[type="file"]:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* Upload Area */
.upload-area {
    position: relative;
    border: 2px dashed #cbd5e0;
    border-radius: 15px;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
}

.upload-area:hover,
.upload-area.highlight {
    border-color: #667eea;
    background: rgba(102, 126, 234, 0.05);
}

.upload-area input[type="file"] {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

.upload-content {
    pointer-events: none;
}

.upload-content i {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 1rem;
}

.upload-content p {
    font-size: 1.1rem;
    color: #4a5568;
    margin-bottom: 0.5rem;
}

.upload-content small {
    color: #718096;
}

/* Image Preview */
.image-preview {
    position: relative;
    display: inline-block;
    margin-top: 1rem;
}

.image-preview img {
    max-width: 200px;
    max-height: 200px;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

.image-preview button {
    position: absolute;
    top: -10px;
    right: -10px;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    border: none;
    background: #e53e3e;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.875rem;
}

/* Button Styles */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

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

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-secondary {
    background: #718096;
    color: white;
}

.btn-success {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
}

.btn-danger {
    background: linear-gradient(135deg, #f56565 0%, #e53e3e 100%);
    color: white;
}

.btn-info {
    background: linear-gradient(135deg, #4299e1 0%, #3182ce 100%);
    color: white;
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

/* Loading Section */
.loading-section {
    text-align: center;
}

.loading-spinner {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 1rem;
}

.loading-section h3 {
    color: #4a5568;
    margin-bottom: 0.5rem;
}

.loading-section p {
    color: #718096;
    margin-bottom: 2rem;
}

/* Progress Bar */
.progress-bar {
    width: 100%;
    height: 8px;
    background: #e2e8f0;
    border-radius: 4px;
    overflow: hidden;
    margin: 1rem 0;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    border-radius: 4px;
    transition: width 0.3s ease;
    animation: progress-animation 2s ease-in-out infinite;
}

@keyframes progress-animation {
    0%, 100% { width: 0%; }
    50% { width: 100%; }
}

/* Quiz Section */
.quiz-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.quiz-meta {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.progress-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.progress-indicator span {
    font-weight: 600;
    color: white;
}

.timer {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(255, 255, 255, 0.2);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-weight: 600;
}

.timer.warning {
    background: rgba(245, 101, 101, 0.8);
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

/* Question Styles */
#questionText {
    font-size: 1.25rem;
    color: #4a5568;
    margin-bottom: 2rem;
    line-height: 1.6;
}

.options-grid {
    display: grid;
    gap: 1rem;
    margin-bottom: 2rem;
}

.option {
    background: #f7fafc;
    border: 2px solid #e2e8f0;
    border-radius: 15px;
    padding: 1rem 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.option:hover {
    background: #edf2f7;
    border-color: #667eea;
    transform: translateX(5px);
}

.option.selected {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: #667eea;
}

.option input[type="radio"] {
    width: 20px;
    height: 20px;
    accent-color: #667eea;
}

.option-text {
    flex: 1;
    font-weight: 500;
}

/* Quiz Navigation */
.quiz-navigation {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 2rem;
}

.question-dots {
    display: flex;
    gap: 0.5rem;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #e2e8f0;
    cursor: pointer;
    transition: all 0.3s ease;
}

.dot.active {
    background: #667eea;
}

.dot.answered {
    background: #48bb78;
}

/* Review Section */
.review-item {
    background: #f7fafc;
    border-radius: 10px;
    padding: 1rem;
    margin-bottom: 1rem;
}

.review-question {
    font-weight: 600;
    color: #4a5568;
    margin-bottom: 0.5rem;
}

.review-answer {
    color: #718096;
    font-size: 0.9rem;
}

.review-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 2rem;
}

/* Result Section */
.result-summary {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
    margin-bottom: 2rem;
}

.score-circle {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.3);
}

.score-number {
    font-size: 2.5rem;
    font-weight: 700;
}

.score-label {
    font-size: 1rem;
    opacity: 0.9;
}

.result-stats {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
    justify-content: center;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem;
    border-radius: 10px;
    min-width: 100px;
}

.stat-item.correct {
    background: rgba(72, 187, 120, 0.1);
    color: #38a169;
}

.stat-item.incorrect {
    background: rgba(245, 101, 101, 0.1);
    color: #e53e3e;
}

.stat-item.time {
    background: rgba(102, 126, 234, 0.1);
    color: #667eea;
}

.stat-item i {
    font-size: 1.5rem;
}

.stat-item span:first-of-type {
    font-size: 1.5rem;
    font-weight: 700;
}

.result-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Footer */
.footer {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    text-align: center;
    padding: 1rem;
    color: #718096;
    margin-top: auto;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
}

.toast {
    background: white;
    border-radius: 10px;
    padding: 1rem 1.5rem;
    margin-bottom: 0.5rem;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    animation: slideIn 0.3s ease;
    max-width: 300px;
}

.toast.success {
    border-left: 4px solid #48bb78;
}

.toast.error {
    border-left: 4px solid #f56565;
}

.toast.info {
    border-left: 4px solid #4299e1;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .main-content {
        padding: 1rem;
    }
    
    .header-content h1 {
        font-size: 2rem;
    }
    
    .card-body {
        padding: 1.5rem;
    }
    
    .quiz-info {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .quiz-meta {
        width: 100%;
        justify-content: space-between;
    }
    
    .options-grid {
        grid-template-columns: 1fr;
    }
    
    .result-stats {
        flex-direction: column;
        align-items: center;
    }
    
    .quiz-navigation {
        flex-direction: column;
        gap: 1rem;
    }
    
    .review-actions,
    .result-actions {
        flex-direction: column;
    }
    
    .input-group {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .header-content h1 {
        font-size: 1.5rem;
    }
    
    .card-header,
    .card-body {
        padding: 1rem;
    }
    
    .score-circle {
        width: 120px;
        height: 120px;
    }
    
    .score-number {
        font-size: 2rem;
    }
}