Pinpointed the Problem: working in IE and Safari, but not in Firefox

I’m trying to create an image gallery using CSS, dHTML and javaScript for a design portfolio at [url]www.apartmentkdesign.com[/url]

the way i want to go about cycling through the images is to actually change the source of the image dynamically using ONE modular function that’s called whenever the “next” or “previous” button is clicked below an image.

it works in Internet Explorer (albeit without fade-in effects) and in Safari perfectly (or perfectly enough), but gets caught up in Firefox, Netscape, Mozilla, and I imagine in other untested Gecko-based browsers.

I’ve pinpointed the problem to this conditional statement:
does anyone know of any compatibility problems?

[CODE]
if((all_imgs[i].className == “full”) && (all_imgs[i].parentElement.style.visibility == “visible”)){
img_id = all_imgs[i].id;
}
[/CODE]

it’s within function “tempCycle” located at [url]www.apartmentkdesign.com/javascript/design.js[/url]

any help would be greatly appreciated!

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