Cinprehensive CSS class and style documentation Declined - Not Valid

Currently we have trouble getting syncfusion controls to look consistent with the bahavior we want even when using basic html/css features from the relevant theme e.g. many features that could be easily created using html/css with bootstrap by applying classes doesn't work because classes cannot be applied to the correct level of the hierarchy using one CssClass parameter. In some parts of the documentation the means to do this using your css classes or ids is provided like Tab header styling, but this is not provided everywhere or in a clear way and its not comprehensive. Some sort of documentation or directory of css classes or explanation of component class composition would help get the basic built in functionality of the CSS framework/theme already in use. Currently it almost feels as if we're losing functionality using these licensed controls over free vanilla bootstrap .