Adding border using CSS to layouts


I try to add a border around some layout in order to use them similar to QFrame from pyQt. However, if I set a css class using css_classes, the border element always gets overruled by some bokeh CSS classes.

I have a couple of plots, tables and other elements on my page and what to make them more separated optically by adding borders (and margins. This part already works)

a) Is there a way to put my CSS class last in order of CSS classes?
b) Is it possible (in future version of bokeh) to have a style option to column, row or grid layout?
c) Is there an alternative option for a structuring element in Bokeh which contains other widgets but has more options for designing them (liek QFrame)?

Thanks in advance.

RĂ¼diger Goetz