Changing Menu Width

How can I change the menu width to 200px? Thanks in advance. Here's the Css:

<style>
#pcm{display:none;}
ul.pureCssMenu ul{display:none}
ul.pureCssMenu li:hover>ul{display:block}
ul.pureCssMenu ul{position: absolute;left:98%;top:-1px;}
ul.pureCssMenu ul ul{position: absolute;left:98%;top:-2px;}
ul.pureCssMenu,ul.pureCssMenu ul {
margin:0px;
list-style:none;
padding:0px 1px 1px 0px;
background-color:#81C348;
background-repeat:repeat;
border-color:;
border-width:0px;
border-style:solid;
}
ul.pureCssMenu table {border-collapse:collapse}ul.pureCssMenu {
display:block;
zoom:1;
_width:115.5px;
float: left;
}
ul.pureCssMenu ul{
width:200px;
}
ul.pureCssMenu li{
display:block;
margin:1px 0px 0px 1px;
font-size:0px;
}
ul.pureCssMenu a:active, ul.pureCssMenu a:focus {
outline-style:none;
}
ul.pureCssMenu a, ul.pureCssMenu li.dis a:hover, ul.pureCssMenu li.sep a:hover {
display:block;
vertical-align:middle;
zoom:1;
background-color:#81C348;
border-width:0px;
border-color:#E4E1DE;
border-style:solid;
text-align:left;
text-decoration:none;
padding:4px;
_padding-left:0;
font:normal 14px Tahoma;
color: #000;
text-decoration:none;
cursor:default;
}
ul.pureCssMenu span{
overflow:hidden;
}
ul.pureCssMenu ul li {
float:none;
}
ul.pureCssMenu ul a {
text-align:left;
white-space:nowrap;
}
ul.pureCssMenu li.sep{
text-align:left;
padding:0px;
line-height:0;
}
ul.pureCssMenu li.sep span{
float:none; padding-right:0;
width:100%;
height:3;
display:inline-block;
background-color:; background-image:none;}
ul.pureCssMenu li:hover{
position:relative;
}
ul.pureCssMenu li:hover>a{
background-color:#47723F;
border-color:#FFFFFF;
border-style:solid;
font:normal 14px Tahoma;
color: #FFFFFF;
text-decoration:none;
}
ul.pureCssMenu li a:hover{
position:relative;
background-color:#47723F;
border-color:#FFFFFF;
border-style:solid;
font:normal 11px Tahoma;
color: #FFFFFF;
text-decoration:none;
}
ul.pureCssMenu li.dis a {
color: #AAAAAA !important;
}
ul.pureCssMenu img {border: none;float:left;_float:none;margin-right:4px;width:24px;
height:24px;
}
ul.pureCssMenu ul img {width:16px;
height:16px;
}
ul.pureCssMenu img.over{display:none}
ul.pureCssMenu li.dis a:hover img.over{display:none !important}
ul.pureCssMenu li.dis a:hover img.def {display:inline !important}
ul.pureCssMenu li:hover > a img.def {display:none}
ul.pureCssMenu li:hover > a img.over {display:inline}
ul.pureCssMenu a:hover img.over,ul.pureCssMenu a:hover ul img.def,ul.pureCssMenu a:hover a:hover img.over{display:inline}
ul.pureCssMenu a:hover img.def,ul.pureCssMenu a:hover ul img.over,ul.pureCssMenu a:hover a:hover img.def{display:none}
ul.pureCssMenu a:hover ul{display:block}
ul.pureCssMenu span{
display:block;
background-image:url(./images/arrow_sub5.gif);
background-position:right center;
background-repeat: no-repeat;
padding-right:12px;}
ul.pureCssMenu li:hover>a>span{ background-image:url(./images/arrow_main4.gif);
}
ul.pureCssMenu a:hover span{ _background-image:url(./images/arrow_main4.gif)}
ul.pureCssMenu ul span,ul.pureCssMenu a:hover table span{background-image:url(./images/arrow_sub5.gif)}
ul.pureCssMenu ul li:hover > a span{ background-image:url(./images/arrow_main4.gif);}
ul.pureCssMenu table a:hover span{background-image:url(./images/arrow_main4.gif)}
</style>

 

Does anyone have any ideas?

 

I always use firebug, it really the easiest way to find the code..