* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;

}

body {
    background: #e8f0fe;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}


.main {
    background: #fff;
    width: 530px;
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
    text-align: center;
    animation: fadeIn 0.8s ease-in-out;
}

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.app h1 {
    font-size: 28px;
    color: #2c3e50;
    font-weight: 700;
    margin-bottom: 20px;
    border-bottom: 2px solid #eee;
    padding-bottom: 15px;
}

.quiz h2 {
    font-size: 20px;
    color: #333;
    margin-bottom: 20px;
    margin-top: 20px;
}

.btn {
    background: #fff;
    color: #333;
    font-weight: bold;
    width: 100%;
    border: 1px solid #ccc;
    padding: 12px;
    margin: 10px 0;
    text-align: center;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn:hover {
    background: #2c3e50;  
    color: #fff;          
}


#next-btn {
    background: #2c3e50;
    color: #fff;
    font-weight: bold;
    width: 200px;
    border: none;
    padding: 12px;
    margin: 20px auto 0;
    border-radius: 6px;
    cursor: pointer;
    display: none;
    transition: all 0.3s ease;
}

#next-btn:hover {
    background: #34495e;
    transform: scale(1.05);
}

.correct {
    background: #d4f8d4;
    border-color: #6a97c4;
    color: #34495e;
}

.incorrect {
    background: #f8d7da;
    border-color: #dc3545;
    color: #721c24;
}