@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;600;700&display=swap');

:root {
    --primary: #4b6cb7;
    --secondary: #182848;
}

body {
    font-family: 'Poppins', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    min-height: 100vh;
    color: #333;
}

.card {
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    border-radius: 15px;
    border: none;
    margin-bottom: 20px;
}

.login-container, .test-container, .results-container {
    max-width: 900px;
    margin: 30px auto;
    padding: 20px;
}

.question {
    margin-bottom: 30px;
    padding: 25px;
    background: #f8f9fa;
    border-radius: 12px;
    border-left: 5px solid var(--primary);
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}

.timer {
    font-size: 1.3rem;
    font-weight: bold;
    color: #dc3545;
    background: white;
    padding: 10px 20px;
    border-radius: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.btn-whatsapp {
    background: linear-gradient(45deg, #25D366, #128C7E);
    color: white;
    border: none;
    padding: 12px 25px;
    font-weight: 600;
    border-radius: 25px;
}

.btn-whatsapp:hover {
    background: linear-gradient(45deg, #128C7E, #25D366);
    transform: translateY(-2px);
    color: white;
}

.progress {
    height: 10px;
    border-radius: 10px;
}

.difficulty-badge {
    font-size: 0.75rem;
    padding: 5px 12px;
    border-radius: 15px;
    font-weight: 600;
}

.difficulty-easy { background: #d4edda; color: #155724; }
.difficulty-medium { background: #fff3cd; color: #856404; }
.difficulty-hard { background: #f8d7da; color: #721c24; }

.student-info-card {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 20px;
}

.nav-btn {
    width: 45px;
    height: 45px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
}

.current-question { background: var(--primary) !important; color: white !important; transform: scale(1.1); }
.answered-question { background: #28a745 !important; color: white !important; }
.hidden { display: none !important; }