I did a bit more troubleshooting but still no luck. I have found the teccc_stylesheet in the uploads folder and it is being correctly called as https:// in the page header.
The page is at: https://discoveryvoyages.com/rates-schedules/
When I use Web Developer Tools to look at the code and styles, I can select the h2 a block level element that is usually colored: h2.tribe-events-list-event-title but it doesn’t have a background-color. The color doesn’t appear to be being overwritten or superceded by another css element. It seems like their is no category-specific selector that would trigger the background-color.
Here is a sample of the css from the teccc_stylesheet:
.tribe-events-category-3-day-classic-voyage h3.tribe-events-list-event-title,
.tribe-events-shortcode .tribe-events-month table .type-tribe_events.tribe-events-category-3-day-classic-voyage,
.tribe-events-list-widget li.tribe-events-category-3-day-classic-voyage h4,
li.tribe-events-list-widget-events.tribe-events-category-3-day-classic-voyage h4,
.events-archive.events-gridview #tribe-events-content table .type-tribe_events.tribe-events-category-3-day-classic-voyage,
.teccc-legend .tribe-events-category-3-day-classic-voyage,
.tribe-events-calendar .tribe-events-category-3-day-classic-voyage,
#tribe-events-content .tribe-events-category-3-day-classic-voyage > .tribe-events-tooltip h3,
.type-tribe_events.tribe-events-category-.tribe-events-category-3-day-classic-voyage h2,
.tribe-events-category-3-day-classic-voyage > div.hentry.vevent > h3.entry-title,
.tribe-events-mobile.tribe-events-category-3-day-classic-voyage h4
{
background-color: #7a209b;
border-left: 5px solid #CFCFCF;
border-right: 5px solid transparent;
color: #fff;
line-height: 1.4em;
padding-left: 5px;
padding-bottom: 2px;
}