Align Images without spacing horizontally and veritcally

Question

I have a group of 4 images that I\'m trying to align vertically and horizontally.

The problem:

I cant get ride of a a small vertical spacing between them.

Answer 1

If you don't have text in this you can just say

ul {
    font-size: 0;
}

This eliminates the space, see modified JSFiddle