Using Bootstrap UI components does not require you to use Bootstrap for layout.
The crazy thing to me is at some point you did learn how the Bootstrap grid works, and I assume you learn how new tools work as a part of your job all the time. But with html and css folks who describe themselves as backend seem to be like "nah".
When bootstrap first arrived there was only floats for grids & nobody was doing responsive design. The first bootstraps did not include responsive elements. Fontawesome wasn't included (gyph). Designers started using it mostly for the JS parts (carousel etc) & grid math.
Bootstrap is great to make an instantly nice site & is useful.
Now that grids/variables etc are here, it is not worth it but I can see why people like it (deep stuff like btn state is done).
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