body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0 1rem;
    background: #fff;
    color: #222;
}

header, footer {
    text-align: center;
    padding: 1rem 0;
    background-color: #f4f4f4;
}

h1, h2 {
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
}

h1 {
    font-size: 2rem;
}

h2 {
    font-size: 1.5rem;
    border-bottom: 2px solid #ddd;
    padding-bottom: 0.25rem;
}

main {
    max-width: 900px;
    margin: 0 auto;
    padding-bottom: 3rem;
}

p {
    margin-bottom: 1rem;
}

ul, ol {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

a {
    color: #007acc;
    text-decoration: none;
}

a:hover, a:focus {
    text-decoration: underline;
}

img {
    display: block;
    max-width: 100%;
    height: auto;
    margin: 1rem auto;
}

details summary {
    cursor: pointer;
    font-weight: bold;
    margin-top: 0.5rem;
    margin-bottom: 0.25rem;
}

details p {
    margin-left: 1rem;
    margin-bottom: 0.75rem;
}

footer p {
    font-size: 0.9rem;
    color: #666;
}

@media (max-width: 600px) {
    body {
        padding: 0 0.5rem;
    }

    h1 {
        font-size: 1.5rem;
    }

    h2 {
        font-size: 1.25rem;
    }
}