Just a quick option... This may or may not work:
I assume you're using JavaScript to do the dynamic CSS changes. From what you've said in your previous post, I assume your code looks something like this:
if (some condition) {
document.getElementById('div_id').style.display = "none";
} else {
document.getElementById('div_id').style.display = "block";
}
Try changing .display = "block" to .display = "".