Reply To: make some images circle and some with circled edges

hello, yes of course.
i would like 2 css codes:
1. https://i.imgur.com/yzdrABr.png i would like to apply rounded corners for images of my choice.
2. and in the same page https://i.imgur.com/ZDOivw5.png i would like one more css code for circle images and to minimise the size of images about 50% ,again for images of my choice.
thank you