I recommend the modern CodyFrame framework, and the main reason is that it has separate elements, i.e. you add to the page what you need as Components, so there is no mess in the code, and the page should load faster, the size of the files will not be huge, yes as in most major CSS frameworks. There are also other reasons, such as the Global Editor ( GLOBALS ), thanks to which your website will not look like hundreds of others based on the same CSS frameworks (you can customize many elements such as colors, typography, buttons, forms ).
Plus many basic Tutorials that you can start with. You can also see this Site Profile, which can be a good start to familiarize yourself with this framework.