body {
    font-family: 'Roboto', Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f9f9f9;
    text-align: center;
}
header {
    background-color: #fff;
    padding: 10px 20px;
    box-shadow: 0px 4px 6px rgba(0, 0, 0, 0.1);
}
header img {
    max-width: 150px;
}
#viewer {
    position: relative;
    width: 100%;
    max-width: 800px;
    height: 600px;
    border: 1px solid #ccc;
    overflow: hidden;
    background: white;
    box-shadow: 0px 4px 6px rgba(0, 0, 0, 0.1);
    border-radius: 8px;
    margin: 20px auto;
}
#loading {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    display: none;
    z-index: 10;
}
#loading .spinner {
    width: 70px;
    height: 70px;
    border: 10px solid rgba(0, 0, 0, 0.2);
    border-left-color: #F4A460;
    border-top-color: #FF4500;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}
@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}
canvas {
    display: block;
    margin: auto;
}
.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background-color: rgba(0, 0, 0, 0.5);
    color: white;
    border: none;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    cursor: pointer;
    transition: background-color 0.3s;
    z-index: 10;
}
.carousel-btn:disabled {
    background-color: rgba(0, 0, 0, 0.3);
    cursor: not-allowed;
}
.carousel-btn:hover:not(:disabled) {
    background-color: rgba(0, 0, 0, 0.7);
}
#prevPage {
    left: 10px;
}
#nextPage {
    right: 10px;
}
.controls-info {
    margin: 20px 0;
    font-size: 16px;
    color: #333;
}
footer {
    background-color: #f1f1f1;
    padding: 20px 10px;
    font-size: 14px;
    color: #666;
    text-align: center;
    border-top: 1px solid #ccc;
}
footer .legal a {
    color: #007BFF;
    text-decoration: none;
    margin: 0 5px;
}
footer .legal a:hover {
    text-decoration: underline;
}