pre
{
    padding : 0 ;
    background-color: white;
    border: 0;
}


.dropdown-content {
    display: none;
    position: absolute;
    background-color: #f9f9f9;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    z-index: 1;
    padding: 12px 16px;
}
.dropdown:hover .dropdown-content {
    display: block;

}