As you can't add css to elements that don't exist you have to add it after you click on the translate dropdown CTA. This jquery works for me.
$('body').click('#google_translate_element', function () {
if (($goog = $('.goog-te-menu-frame').contents().find('body')).length) {
var stylesHtml = '<link rel="stylesheet" href="/css/google-translate.css">';
$goog.prepend(stylesHtml);
}
});
With this css.
.goog-te-menu2 {
width: 300px!important;
height: 300px!important;
overflow: auto!important;
}
.goog-te-menu2 table,
.goog-te-menu2 table tbody,
.goog-te-menu2 table tbody tr {
width: 100%!important;
height: 100%!important;
}
.goog-te-menu2 table tbody tr td {
width: 100%!important;
display: block!important;
}
.goog-te-menu2 table tbody tr td .goog-te-menu2-colpad {
visibility: none!important;
}