.code-copy-icon {
    position: absolute;
    top: 10px;
    right: 10px;
    width: 20px;
    height: 20px;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.15s;
    color: #a3aab1;
}

pre:hover .code-copy-icon {
    opacity: 1;
}

.code-copy-icon:hover {
    color: #506784;
}