This is just a suggestion - When I get something wrong in the Japanese course, I’m sometimes asked to re-write it. That’s awesome, but its hard to read what I wrote because it’s so small. I think this text should be larger and red or something. Especially with kanji, its just too hard for me to read. See the screenshot below for what I’m talking about.
Edit: Make it the size and font of the furigana line, for example.