I have a webpart which renders a html as below:

<table width="100%" cellpadding="0" cellspacing="0" border="0">
<td id="MSOZoneCell_WebPartWPQ8" vAlign="top"><table TOPLEVEL border="0" cellpadding="0" cellspacing="0" width="100%">
<td valign="top"><div WebPartID="a0d356f1−3e14−45bf−a1f1−9f3d2a5eff00" HasPers="false" id="WebPartWPQ8" width="100%" class="ms−WPBody" allowDelete="false" style="height:425px;overflow:auto;" >

<i f rame frameBorder="0" border="0" width="100%" height="100%" overflow−x="visible" marginwidth="0" marginheight="0" marginTop="100px" scrolling="no" src="http://css.override.com/countup_flash.html">
<div class="UserGeneric">The current browser does not support Web pages that contain the IFRAME element. To use this Web Part, you must use a browser that supports this element, such as Internet Explorer version 5 or later.</div>

I need to change the css (remove outlining border) only from that webpart without touching any other webpart on the page.
This can be done by overriding css for that particular webpart, as shown below:

#MSOZoneCell_WebPartWPQ8 div.ms-WPBody{
border-left:none !important;
border-top:none !important;
border-right:none !important;
border-bottom:none !important;
padding-left:0px !important;
padding-top:8px !important;
padding-right:0px !important;
background-color:#ffffff !important;