.spv-container {
    margin-bottom: 30px;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
    max-width: 100%;
    text-align: center; /* Center the button */
}

.spv-download-link {
    display: inline-block;
    background-color: #0073aa; /* Standard WP Blue, slightly different shade */
    color: #fff;
    text-decoration: none;
    padding: 15px 30px; /* Larger padding */
    font-size: 18px; /* Larger font */
    border-radius: 5px;
    margin-bottom: 20px;
    font-weight: 600;
    transition: all 0.2s ease;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    border: none;
    cursor: pointer;
    line-height: 1.2;
}

.spv-download-link:hover,
.spv-download-link:focus {
    background-color: #005177;
    color: #fff;
    text-decoration: none;
    transform: translateY(-2px); /* Lift effect */
    box-shadow: 0 6px 10px rgba(0,0,0,0.15);
}

.spv-download-link:active {
    transform: translateY(0);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.spv-pdf-viewer {
    border: 1px solid #ddd;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    border-radius: 4px;
    overflow: hidden;
    background: #f9f9f9;
    max-width: 100%;
    margin: 0 auto; /* Center the viewer if it has max-width */
}

@media screen and (max-width: 600px) {
    .spv-pdf-viewer {
        height: auto !important;
        min-height: 500px; /* Ensure at least some visibility on mobile if auto fails */
    }

    .spv-download-link {
        display: block; /* Full width button on mobile */
        width: 100%;
        box-sizing: border-box;
    }
}