I am using Business Feature on a subsite: and I am having

I am using Business Feature on a subsite: and I am having a problem with style. The options do not seem to work (I have custom enabled). So I've tried to change in child theme. However, here I am confused: which style.css am I supposed to use in the child them? The one in the root (which is what I usually use with other themes) or the one in the .inc/css folder? I am trying to change the orange title plug-info h1 to #5400A3 (actually all text that is currently orange to #5400A3