Targetting Images for Zooming
 

I have a working page that enables the clicking of a series of images for zooming in and out. The code shows the images in the usual <ul></uk> and <li></li> format. The thing is, I have a page that already contains images outside of a listing format. This page is responsive and I would like to keep the code for images as it is. (I followed a flexbox tutorial and I'm very happy I understand how the page is made up!)

My question is, how can I target an image with the CSS3 code already in place for the listing formatted page? I've tried to do it myself but without success.
Please Help.
Thanks !
I didn't find the right solution from the internet.
References:
- [url]http://www.htmlforums.com/forum/website-development/css/1442897-targetting-images-for-zooming[/url]
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