Does heavy traffic cause CSS malfunctions?

I just launched my site yesterday and everything was working as is. I have a blogs community page, and a questions community page that each have a top blogger/top commenters section, as well as a top askers/top answers section. They all share the same CSS and have an image that holds user pics that use CSS to align properly

I noticed as the number of users started to get over 200, ONLY on the blogs page, and only the first pic in the first row of four, and the first pic in the second row of four were out of line. ONLY in 开发者_StackOverflow中文版firefox, not in IE,safari or Chrome

Any idea what this may be? Here is the structure

<td class="topCommentPic round_10px">
                    <a href="<?php echo $author->url(); ?>">
                        <img src="<?php echo $author->img('mini'); ?>" border="0" />
                    </a>
                    <div class="topCommentName">
                        <a href="<?php echo $author->url(); ?>">
                            <?php echo $author->first_name; ?><br /><?php echo $author->last_name; ?>
                        </a>
                    </div>
                </td>

Let's think for a little bit. How would the number of users on the server affect how a browser on the other side of the world from your server renders HTML?

This is highly unlikely - especially when determining the cause of such a small discrepancy.

Could the number of users on the server affect what the server sends to clients?

...Most likely, the only thing it could possibly affect is a "# users online" section on the webpage. I would start looking there - specifically, it may now be overrunning the space allowed for it slightly.

The CSS is sent by your server and executed (read) by the client's browser in order to display a nice web page.

There is no way the client-side execution of the CSS can be influenced by the number of online visitors. Same remark goes for the HTML or JS.

However your server load can (and is) influenced by the number of users. If your server load is too high, undefined reaction can happen. And your server my close a connection before having sent the whole CSS file. Try checking your server load.

Take also care at some "list of online users" of such things witch can quickly destroy a template by taking much more page space than you initially thought.

I've got a completely random idea....... Try pressing Ctrl+0 (Control and Zero) on your keyboard and see what happens. Sometimes Firefox zoom causes distortions and can only be properly reset with Ctrl+0. Pulled my hair out once wondering what was wrong with my screen.