Styling Mac Desktop display?

I’m a Mac User impressed with this program and a little daunted by the level of tech sophistication involved. But I want to try. I’m using 1.0.201 on an iMac running High Sierra and have sync working with Dropbox, etc. But I’m also a 79 year old guy with some vision issues. Is there a way that I can style the presentation of the applicaiton window? I see in preferences that I can up the size of font used in the text input window. But the text in the sidebar, toogle note list, and the Markdoiwn Preview is far too small for me to read well. Perhaps this is a matter of CSS? Is there a sample CSS file available (rather than a blank one), were I might be able to figure out how to edit font size? Is the CSS used for writing the window available somewhere? Thanks so very very much for any suggestions.

Sorry. Got it! I findally found the zoom option under Tools, and that will do.