#header   { position: fixed; z-index: 400; top: 0; left: 0; width: 100%; height: 145px }
#nav      { position: fixed; z-index: 390; top: 146px; left: 0; width: 170px; height: 100% }
#mainblock { position: absolute; top: 166px; left: 190px; z-index: 1; margin-right: 20px; }
body { margin: 0 20px 0 0; }