body {
    font-family: Arial, sans-serif;
    text-align: center;
    background: yellow;
    margin: 0;
    padding: 20px;
}

header {
    background: orange;
    padding: 15px;
    font-size: 24px;
    font-weight: bold;
    color: white;
}

.class-buttons button {
    background: blue;
    color: white;
    font-size: 18px;
    padding: 10px;
    margin: 10px;
    border: none;
    cursor: pointer;
    border-radius: 5px;
}

.hidden {
    display: none;
}

#quiz-container {
    margin-top: 20px;
}

#question-image {
    width: 200px;
    height: auto;
    margin: 20px;
    border: 2px solid black;
    border-radius: 10px;
}

#options button {
    font-size: 20px;
    padding: 10px;
    margin: 5px;
    background: green;
    color: white;
    border: none;
    cursor: pointer;
    border-radius: 50%;
}

footer {
    margin-top: 20px;
    background: orange;
    padding: 10px;
    color: white;
}