setting maximum height limit for webpart to grow.

i am using xsl stylesheet for styling a list view web part. In the webpart properties i can set the height as fixed or not. I want to be able to set a fixed height of maximum limit eg. 200px. What i mean is if the height of the webpart is below 200px it will shrink and extend as it does in the case when no fixed height is given,. But as soon as height exceeds 200px a scroll bar appears i.e the webpart can shrink to any limit but cannot grow beyond 200px. How can i do this. curretly i have set a fixed height and when the height is below 200px a lot of empty space can be seen which doesnt look good. can someone pls help out.

thanks

aparna