How to change colours in Dictionary

Bootjack

Bringing up the Collins Dictionary, the word given on the left side (word I'm looking up) is in a deep blue and hard to see on the black background. 

I can highlight a word and in the 'highlight' a word and right click on it and it gives me the option to change that one word to, let's say, a yellow. But what do I do in order to get all the words listed on the left to become a yellow colour, as seen in the screenshot I'll show here. 

Bootjack

Apparently, I've got everyone stumped on this one. I would delete the question but I cannot. Sorry.