Changing the bootstrap.css files for color changes

Thanks for any help someone may give on this.

I am using the OC version latest 4.0.2.3 the default template as out of the box, no other installed template. Just loading up my changes and items to use it as it is installed. I just wanted to change the colors on it a bit.

I am trying to change the background color. I found it in the bootstrap.css file in catalog/view folder and changed the white color (hex #), refreshed cashes on admin/home page and I still can not get it to show any change anywhere on my online site.

Would anyone know what I may be doing wrong? Had been using version 1.5.5.1 for years, yet with a template, and had to upgrade a bit, with all the new security and php upgrades. It won't work anymore with my server hosting.

Would I have to make these color theme changes to the .css files before I upload to my server and prior to the original Install of the OpenCart program? Have tried about everything but that.

This new version is so nice and quick and works so great, if I could just change a few colors away from the box-top OpenCart theme it would be all I need.

Please help if you can. Thanks.

I would add the change to the stylesheet.css and not the bootstrap.css. Also make sure you refresh your browser cache. Use your web browser's developer tool to check the response contains your changes.

Thanks, the developer tool is GREAT!

opencart-4.0.2.3 has a main color of aqua blue that I can not find. Found all but the one that colors the category drop-down button when the window is pulled in on a mobile device. Same color as this form's "Submit" button looks like. Have looked nearly everywhere....... rgb 34,154,200 or .bg-primary or primary-rgb they show up in the browser tool but can't find in any of the css or scss files. Its there main theme color.

Thanks for the help !