How can i set a stylesheet to a string ?

$shtml = "text below"

and the stylesheet being,

HTML Code:
<style type="text/css">
.mygen { Created using MyGen 2.5 - www.mygen.co.uk }

.mygen { Background Properties }
table, tr, td { background-color:transparent; border:none; border-width:0;}
body {
	background-color:AAAAAA;
	border-color:442222;
	border-width:3px ;
	border-style: solid;
	scrollbar-face-color:000000;
	scrollbar-highlight-color:000000;
	scrollbar-3dlight-color:000000;
	scrollbar-shadow-color:000000;
	scrollbar-darkshadow-color:000000;
	scrollbar-arrow-color:000000;
	scrollbar-track-color:000000;
	 }

.mygen { Table Properties }
table table { border: 0px }
table table table table{border:0px}
table table table {
	border-style:outset;
	border-width:2px;
	border-color:99BB77;
	background-color:transparent;
	   		}

table table table td {
	background-color:BBDD99;
	filter:alpha(opacity=60); -moz-opacity:0.60; opacity:0.60; -khtml-opacity:0.60; }
table table table table td {filter:none;}

.mygen { Text Properties }
table, tr, td, li, p, div { font-family:courier new; color:000000; font-size:14px;     } 

.mygen { Miscellaneous Properties }
a:hover img { filter:Wave(Add=0,  Freq=5,  LightStrength=20,  Phase=220,  Strength=10);}
body { cursor:crosshair;}
a:hover { cursor:crosshair;}
</style>

    }