body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 20px;
    background-color: #f0f0f0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background-color: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

h1 {
    color: #333;
    text-align: center;
    margin-bottom: 20px;
}

#function-form {
    text-align: center;
    margin-bottom: 20px;
    font-size: 1.2em;
}

#minmax-info {
    text-align: center;
    margin: 20px 0;
    font-size: 1.2em;
    color: #444;
    font-weight: bold;
}

#plot {
    width: 100%;
    height: 500px;
    margin: 20px 0;
    background-color: white;
    border: 1px solid #ddd;
    border-radius: 4px;
}

#nextProblem {
    display: block;
    margin: 20px auto;
    padding: 10px 20px;
    font-size: 1.1em;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s;
}

#nextProblem:hover {
    background-color: #45a049;
}

/* Mobile Responsive Design */
@media screen and (max-width: 768px) {
    body {
        padding: 10px;
    }

    .container {
        padding: 15px;
    }

    h1 {
        font-size: 1.5em;
    }

    #function-form, #minmax-info {
        font-size: 1em;
    }

    #plot {
        height: 400px;
    }

    #nextProblem {
        width: 100%;
        padding: 15px;
    }
}

@media screen and (max-width: 480px) {
    h1 {
        font-size: 1.3em;
    }

    #function-form, #minmax-info {
        font-size: 0.9em;
    }

    #plot {
        height: 300px;
    }
}