1. Resolved!
In The Events Calendar Pro recommended theme Gameplan …
Gameplan has overridden those colors.
But if you want to return the default settings, please fix the following:
1. Open file ”/themes/gameplan/style.css” find and delete this line:
.events-archive.events-gridview #tribe-events-content table .vevent{margin:0; background:#e23e38;}
// about line 1682
2. Open file “themes/gameplan/css/custom.css.php, find and delete this line
.events-archive.events-gridview #tribe-events-content table .vevent{background:<?php echo $gp_main_color ?>}
// about line 397
2. Still unresolved