MediaWiki:Vector.css

.copy-button {
    position: absolute;
    top: 10px;
    right: 10px;
    background-color: #444;
    color: white;
    border: none;
    border-radius: 5px;
    padding: 5px 10px;
    cursor: pointer;
    font-size: 12px;
}

.copy-button:hover {
    background-color: #666;
}

div.mw-highlight {
    position: relative;
    display: block;
    padding-top: 30px; /* Add space for the button */
    border-radius: 5px;
    overflow-x: auto;
    background-color: #444;
}