#ref_cat_slice {
    border: 1px solid gray;
    padding: 1ex;
}

#ref_cat_slice form.downloadform input:invalid:not(:placeholder-shown) {
    color: red;
    font-weight: bold;
}

#ref_cat_slice a.downloadlink,
#ref_cat_slice a.indexlink {
    display: inline-block;
    border: 2px solid gray;
    padding: 0.2ex;
    margin: 0.2ex;
    color: gray;
    background-color: lightgray;
    text-decoration: none;
}

#ref_cat_slice a.downloadlink[href],
#ref_cat_slice a.indexlink[href] {
    border: 2px outset gray;
    padding: 0.2ex;
    color: black;
    background-color: lightgray;
}