body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    margin: 0;
    line-height: 1.6;
    color: #333;
    background-color: #f4f4f4;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: #0056b3;
    color: #ffffff;
    padding: 40px 0;
    text-align: center;
}

header h1 {
    margin: 0;
    font-size: 2.5em;
}

header p {
    font-size: 1.2em;
}

main {
    padding: 20px 0;
}

.api-info, .books-section, .contact-section {
    background: #ffffff;
    margin: 20px 0;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.api-info h2, .books-section h2, .contact-section h2 {
    color: #0056b3;
}

.cta-button {
    display: inline-block;
    background: #007bff;
    color: #ffffff;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 5px;
    margin-top: 10px;
}

.cta-button:hover {
    background: #0056b3;
}

footer {
    background: #333;
    color: #ffffff;
    text-align: center;
    padding: 20px 0;
}