Ahoj, díky pomohl bys mě prosím jenom kam to mám zapsat ?

/* CSS styles */
a {color:#e7e7e7;text-decoration:none;}
a:hover {color:#aaff00;text-decoration:none;}

body {background:url(images/bg.jpg);
background-position:center top;margin:auto;font-family:Arial;font-size:12px;color:#e7e7e7;}
.body2 {width:998px;height:100%;padding:14px 0 0 0;background:#181818;border:1px solid #3d3d3d;border-top:none;margin:0 auto 20px auto;}

#header {width:1000px;height:140px;margin:auto;}
#header .header {padding:20px 0 0 20px;}