[Plugin: SortTable Post] CSS suggestion

To make this compatible with more themes, I suggest you remove most of the CSS the plugin adds. It could be reduced to

table.sortable thead tr {cursor: pointer;}
table.sortable tr:nth-child(2n) {background-color: rgba(0,0,0,0.1);}
table.sortable th:hover:not(.sorttable_nosort) {background-color: rgba(99,0,0,0.2);}
.sorttable_nosort {cursor: default;}

https://www.ads-software.com/extend/plugins/sorttable-post/