Need border on images with border radius Canvas

Hello again!

I have made some images on my site round by setting the border radius to 50%. Now, I would like to add a shadow or at least a border to these images. I am still getting a hang of how to alter things in CSS (darn ids and classes) so I am struggling with this one. I found another question on the topic yet do not know if the solution would apply to me.

My website is and one of the pages with circular images is: http://digitalreachopm.com/about-us/

I am not sure if I would add CSS that would affect all round images or if I need to do that and change the way in which I add the radius to the image.

Thank you for your guidance on how to make this alteration!

Pura Vida,
Mandy