Square Thumbnails via CSS *ONLY* - no access to HTML strcuture

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Project Budget (USD)
$30 - $250

Project Description:
I'm trying to edit an image gallery and - whilst I have access to a 'custom' css template, I have no access to the HTML itself, nor how the images are placed within it. In turn, I can't introduce any divs, so the 'clipping' property I'd read about doesn't seem to be functioning as it should.

Here's the HTML code for a single image:

And this is as close as I've been able to get the CSS:

.thumbnails li {
width: 88px;
height: 88px;
overflow: hidden;
margin: 4px;
padding: 3px; }

.printSample {
border: 0px !important; }

Result: http://store.offprint.am/category.php?event=762297&id=1895982

Even though the images (somewhat) are square (you can see a slight discrepancy in size between the first, second and third images [H V V]) they're displacing(?) the values on the opposite side - so if I add a border, it's omitted on the right side of a horizontal and on the bottom of a vertical.

What I'm after is a square thumbnail (without distorting the image), 1px margin around it, 1px solid border (ccc) around that (all sides) and then 4px between one thumbnail and the next.

Potential issues:

- the website has a 'no right click' thing which is a bit of bother and can't be disabled. Opera ignores it and Chrome has an extension to do the same.
- the website has EXISTING stylesheets that I don't have access to - only the ability to override those functions with custom.css
- edits that I've made are at the very bottom, but I don't know if any of the other code is of relevance ..so I've left it in.

Just need this one thing amending for now - but most likely more down the road.

Additional Project Description:
02/25/2013 at 11:01 IST
Because the HTML from the above seems to have been omitted, the code missing can be found in the 'code.txt' attachment.

Skills required:
Additional Files: custom.css code.txt
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