Confusing UI [+suggestion]
I find it a bit confusing that selected sentence and hovering over a sentence invoke the same style change.
At a glance it seems that I have selected both of the sentences so I always have to pause and double check before I press enter.
This happens a lot since I mostly use my keyboard when practicing and I tend to leave my cursor on the right side of the screen after I use my mouse to peak or check the discussion.
possible solution = different styles for selecting and hovering over a sentence.
Agreed. Whenever I have a multiple choice question, and I see that it's highlighted another answer when I've only ticked once I always hold my breath in hope I don't lose a heart. Thankfully I never have when this has occurred, but just the possibility makes you nervous!