rounded images

Hi!

I have been using the following code to round the edges of my images. `#main-content img{border-radius:50%!important;}
`

I have been putting it in the custom css in the specific visual composer pages.

However, on my homepage, I want it to only apply to the images in the teaser boxes below the header, and not to the insurance banner above the contact form. I tried making a custom class, but for some reason it is not working. Any ideas? Thanks SO MUCH!