A. You can compose components the same way Bootstrap does, but using semantic classes. For example, if Bootstrap is using "thumbnail-container", you could call your class "product-thumb-container". Because of the way HTML works, container classes are often necessary, and they can be semantic. Think about a legal document: at the end of them, you have appendices. An appendix is like a container: it's factored into the overall structure, but it also has a semantic value. You can't move an appendix somewhere else and still call it an appendix.
B. You can use only the parts of Bootstrap that you want, so you could leave components out altogether. As mentioned above, this might be a better option for a larger project with fine-grained, custom designs.
A. You can compose components the same way Bootstrap does, but using semantic classes. For example, if Bootstrap is using "thumbnail-container", you could call your class "product-thumb-container". Because of the way HTML works, container classes are often necessary, and they can be semantic. Think about a legal document: at the end of them, you have appendices. An appendix is like a container: it's factored into the overall structure, but it also has a semantic value. You can't move an appendix somewhere else and still call it an appendix.
B. You can use only the parts of Bootstrap that you want, so you could leave components out altogether. As mentioned above, this might be a better option for a larger project with fine-grained, custom designs.