default sizes for main column and one sidebar

I was playing around with column sizes in the Editor (I know, not a good idea) and lost my notes as to the default pixel sizes for the wrapper, main column and one sidebar. Appreciate if you can let me know, and I'll get them back to where they belong. Site is: https://www.digitalbodies.net The site is working fine but is a little jumpy on a mobile device here and there - probably because I messed something up! Other question I had: is it critically important to makes sure all featured images are not larger than the 780 x 586 specified in the instructions? Thanks in advance - Clean Journal Pro is a great theme!