Autoresize Element (div) to Fit Horizontal Content

I tried googling, but didn't come up with much. I'm building a horizontal carousel which displays images in a LI, floated. The issue I want to solve is, everytime I add thumbnails to the carousel (I'm lazy loading), I need to recalculate the width of the carousel (so that all the floated thumbnails line up nicely side by side).

For one, I rather not have to do these kinds of calculations in JS, and for two, I found that it's hard to find a cross browser way to ensure that the width will be properly calculated (I end up having to add or remove pixels from the total width depending on the browser).

So my question is, is there any way without JS, to be able to add content to a div, and have the width adjust as needed, the same way a div's height would?

And if not, have you found a more efficient way to handle this scenario than recalculating the width every time?

I'm not new to web dev, and for as long as I've been in this field, to my knowledge this has never been possible. But with the advent of new technologies cropping up, I thought maybe there was an obscure way of achieving this now.

Thanks in advance!

[EDIT] (for clarification, but simplified): If my carousel is 500px wide with overflow hidden. There's a slideable section containing thumbnails, each is 100px wide, floated, they fit 5 across in the carousel. When a user clicks Next, it lazy loads the next set of 5 thumbnails, and appends it to the slider area after the first set of 5. But since this div was 500px wide to accommodate 5 thumbnails, adding another 5, I need to recalculate the width to get the new thumbnails to show up s开发者_StackOverflow社区ide by side. Ideally I'd like to find a way to have the div autoresize its width to fit horizontal content, the same way it naturally does for vertical content.

I've found that using a containing carousel div with white-space: nowrap and overflow: hidden has worked. I then have display: inline-block for each item in the div.

Using this class for each individual item:

.eachItem {
   display: inline-block;
}

Will work (I've done something similar to that).

The problem is that in IE7 it won't work! and you'll have to use JavaScript anyway :(

EDIT: I meant inline-block... and as you may know, IE7 doesn't "like" it.