styles.css

 body, body * {
     font-family: arial;
     font-weight: normal;
}
 .sr-only {
     position: absolute;
     top: -30em;
}
 table.sortable {
     width: 100%;
}
 table.sortable td, table.sortable th {
     padding: 0.125em 0.25em;
     width: 8em;
}
 table.sortable td a {
     color: black;
}
 table.sortable td a:hover {
     text-decoration: underline;
}
 table.sortable tbody tr:hover td {
     background-color: lightgrey;
}
 table.sortable th {
     font-weight: bold;
     border-bottom: thin solid #888;
     position: relative;
}
 table.sortable th.no-sort {
     padding-top: 0.35em;
}
 table.sortable th:nth-child(5) {
     width: 10em;
}
 table.sortable th button {
    /*position: absolute;
    */
     padding: 4px;
     margin: 1px;
     font-size: 100%;
     font-weight: bold;
     background: transparent;
     border: none;
     display: inline;
     right: 0;
     left: 0;
     top: 0;
     bottom: 0;
     width: 100%;
     text-align: left;
     outline: none;
     cursor: pointer;
}
 table.sortable th button span {
     position: absolute;
     right: 4px;
}
 table.sortable th[aria-sort="descending"] span::after {
     content: "▼";
     color: currentcolor;
     font-size: 100%;
     top: 0;
}
 table.sortable th[aria-sort="ascending"] span::after {
     content: "▲";
     color: currentcolor;
     font-size: 100%;
     top: 0;
}
 table.show-unsorted-icon th:not([aria-sort]) button span::after {
     content: "♢";
     color: currentcolor;
     font-size: 100%;
     position: relative;
     top: -3px;
     left: -4px;
}
 table.sortable td.num {
     text-align: right;
}
 table.sortable tbody tr:nth-child(odd) {
     background-color: #f7f7f7;
}
/* Focus and hover styling */
 table.sortable th button:focus, table.sortable th button:hover {
     padding: 2px;
     border: 2px solid currentcolor;
     background-color: #eeeeee;
}
 table.sortable th button:focus span, table.sortable th button:hover span {
     right: 2px;
}
 table.sortable th:not([aria-sort]) button:focus span::after, table.sortable th:not([aria-sort]) button:hover span::after {
     content: "▼";
     color: currentcolor;
     font-size: 100%;
     top: 0;
}