[Plugin: WP-Table Reloaded] Header row background color

I saw in the FAQ that I should set the header row color by adding this to the Custom CSS in the plugin options:

.wp-table-reloaded th, .wp-table-reloaded .sorting {
background-color: #FF0066!important;
}

However, you can see on this page:
https://sites.ieee.org/schenectady/executive-committee-members/

that the column headers (first row of the table) are still dark gray. Can you please let me know what I need to change to change the color of the first row (column headers)?

Thanks!

David

https://www.ads-software.com/extend/plugins/wp-table-reloaded/