Merge the class. Foe example, .hh{margin:0px}, .hh{width:10px} will be merged into .hh{margin:0px,width:10px}. But .hh li{float:left} or
.hh, dd{float:left} will not be merged.
Find and remove the unused class and id in CSS (optional). Without considering the class or id names in <pre> </pre> tag or other text area.
Shortcut margin and padding. For example, {margin-top:10px; margin-right:20px; margin-bottom:5px;margin-left:20px} is simplifed to {margin: 10px 20px 5px 20px}