:root {
    --bg-color: #121212;
    --primary-color: #1DB954;
    --text-color: #E0E0E0;
    --text-color-dark: #B3B3B3;
    --container-bg: #181818;
    --container-highlight: #282828;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    text-decoration: none;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    color: var(--text-color);
    background-color: var(--bg-color);
}

hr {
    border: none;
    border-top: 1px solid var(--container-highlight);
    margin: 15px 0;
}

.header {
    text-align: center;
    color: var(--text-color);
    padding: 40px 20px;
}

.header h1 {
    font-size: 2.5em;
    font-weight: 700;
    margin-bottom: 10px;
}

.header p {
    font-size: 1em;
    color: var(--text-color-dark);
}

.book-container {
    background-color: var(--container-bg);
    border-radius: 15px;
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
    margin: 0 20px;
    padding: 20px;
    border: 1px solid var(--container-highlight);
}

.book-header {
    text-align: center;
    margin-bottom: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
}

.book-header img {
    max-width: 80px;
    border-radius: 8px;
}

.book-title {
    color: var(--text-color);
    font-weight: bold;
}

.book-title p {
    font-size: 14px;
    color: var(--text-color-dark);
}

footer {
    padding: 20px;
    text-align: center;
    color: var(--text-color-dark);
    flex-shrink: 0;
}

footer > p, footer a {
    font-size: 14px;
    color: var(--text-color-dark);
}

@media (max-width: 768px) {
    .header h1 {
        font-size: 2em;
    }
    .book-container {
        margin: 0 10px;
        padding: 15px;
    }
}