background image in css class

[audiogirl]

I know this is a common question but have been looking for hours and I can't seem to find one that is for a background image that is in a table using a class (not in an ID) - I should have built the whole site in css but i'm not that good at it yet!

this is where i want the image to go

<td class="happen">

in this page

http://www.23rdandunion.org/happen.htm

this is my css

td.happen {background-image:url(../images/happen.jpg); background-repeat:no-repeat; height:566px;}

[audiogirl]

oops! i forgot to mention that i want the image to change on refresh.