By default, the platform does not have this option. You can use the following CSS code.
Please follow the steps below:
1. Go to BuddyBoss – Theme Options
2. Under Custom Codes, enable CSS
3. Append the following:
.learndash-wrapper .learndash_content_wrap .learndash_mark_complete_button {
background-color: #FF0000;
}
4. Save changes.
Screenshots
Without Code (default color):
With Code (and color code):