Writing CSS stylesheet today can be a nightmare. With the high number of specific browser prefixes, we might end up banging our heads against the wall in the effort of not forgetting how to be sure our code is cross browser compatible.
Just to make things clearer: let's consider the following CSS:
.container {
-moz-border-radius: 4px 0px 0px 4px;
-webkit-border-radius: 4px 0px 0px 4px;
border-radius: 4px 0px 0px 4px;
-webkit-box-shadow: 0 0 4px #9c9c9c;
-moz-box-shadow: 0 0 4px #9c9c9c;
box-shadow: 0 0 4px #9c9c9c;
}