How do I turn off this CSS code for one text widget on my sidebar?

Here is the CSS that came with my template for my sidebar. I like the CSS but on some text widgets I would like to turn it off for only that text widget. What do I need to do to make that happen?

/* The Sidebar */

#sidebar {
width:200px;
float:right;
font-size:12px;
color:#999;
margin: 10px 10px 0px 0px;
font-family:century gothic,Verdana,sans-serif;

}

#sidebar ul {
margin:0;
padding:0;
list-style-type:none;
}

#sidebar h2 {
font-size:18px;
height:25px;
font-weight:bold;
padding:3px 0px 0px 5px;
background:#323232;
Margin: 10px 0 0 0;
color:#fff;
font-variant:small-caps;
}

#sidebar li a {
display:block;
line-height:160%;
padding:4px 0 4px 0;
color:#222;
background:#C0C0C0;
border-bottom:1px solid #464646;
}

#sidebar li a:hover {
text-decoration:none;
background-color:#ae0000;
color:#fff;

}

#sidebar ul li a {
background:#none;
padding-left:10px;
}
#sidebar table {
width:100%;
text-align:center;
background-color:#464646;
}