style.css does not affect h2 font size in sidebar

link to your url so we may peep your css please

some themes style the h2 title tag in the sidebar with an extra css statement – for instance something like:
#sidebar h2 { font-size: 12px; }
you will find this, or something similar, further down in the style.css file.

I did find link to style in source of https://tips-wordpress.com, so you should also.
#sidebar h2 is not present.

make a new style and add it to style.css:
h2.widgettitle {font-size: 22px; }

alchymyth, that worked great. Thanks! (I used 12pt.)
What might the equivalent be for Page/Post titles?