Can someone check this for me? I am new to all of this stuff, and have been trying to change a few things and it looks like I keep messing up this CSS or JS file.

The CSS file in question are at:

I have been having numerous problems. All I was trying to do was change the image size. Can someone find out what the CSS issue is? And can someone tell me how to do change the image size? I don't want to keep messing up the CSS file

Thanks for your help in advance.