Transparent code for blog Options

[predisp0siti0n]

i put this code in

<!-- begin code provided by createblog.com --><br /><style type="text/css"><br />table.blogbody {<br />border: 1px dashed #000000;<br />background-color: #000000;<br />filter: alpha(opacity=70);<br />width:600px;<br />}<br /></style><br /><!-- end code provided by createblog.com -->

and thats basically what i want except i want it to be semi transparent enough so i can see the background on my site, but still be able to read the white text when you scroll over it, what is the code for that?

My Webpage

[predisp0siti0n]

No i wanna be able to see the picture behind it when its over, when i change the opacity nothing changes