* {
    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%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

.header {
    text-align: center;
    color: white;
    margin-bottom: 50px;
    padding: 40px 20px;
}

.header h1 {
    font-size: 48px;
    margin-bottom: 10px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.header p {
    font-size: 18px;
    opacity: 0.95;
    text-shadow: 0 1px 5px rgba(0, 0, 0, 0.2);
}

.exam-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.exam-card {
    background: white;
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

.exam-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.3);
}

.exam-title {
    font-size: 22px;
    font-weight: bold;
    color: #2c3e50;
    margin-bottom: 15px;
}

.exam-info {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 20px;
}

.exam-time {
    color: #7f8c8d;
    font-size: 14px;
    display: flex;
    align-items: center;
}

.exam-time strong {
    color: #2c3e50;
    display: block;
    font-size: 13px;
    margin-bottom: 3px;
}

.exam-status {
    display: inline-block;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: 10px;
    width: fit-content;
}

.status-upcoming {
    background-color: #fff3cd;
    color: #856404;
}

.status-active {
    background-color: #d4edda;
    color: #155724;
    animation: pulse 2s infinite;
}

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

.status-ended {
    background-color: #f8d7da;
    color: #721c24;
}

.btn {
    display: inline-block;
    width: 100%;
    padding: 14px 24px;
    background-color: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 8px;
    margin-top: 20px;
    transition: background-color 0.3s, transform 0.2s;
    border: none;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    text-align: center;
}

.btn:hover:not(:disabled) {
    background-color: #2980b9;
    transform: scale(1.02);
}

.btn:disabled {
    background-color: #95a5a6;
    cursor: not-allowed;
    opacity: 0.6;
}

.btn-success {
    background-color: #27ae60;
}

.btn-success:hover {
    background-color: #229954;
}

.empty-state {
    text-align: center;
    color: white;
    padding: 60px 20px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    backdrop-filter: blur(10px);
}

.empty-state h2 {
    font-size: 28px;
    margin-bottom: 10px;
}

.empty-state p {
    font-size: 16px;
    opacity: 0.9;
}

.footer {
    text-align: center;
    color: white;
    margin-top: 60px;
    padding: 20px;
    opacity: 0.8;
    font-size: 14px;
}

@media (max-width: 768px) {
    .header h1 {
        font-size: 36px;
    }
    
    .exam-list {
        grid-template-columns: 1fr;
    }
    
    .exam-card {
        padding: 20px;
    }
}