basic: use prewin.h

Change-Id: I49b797b170b3fd74324eede9d3b6b6ec106e62e4
use our css prefix to make this readable

Change-Id: I360832edafcfcff7e63fd3b185c2575165c2d728
remove external header guards

that's the problem with those: none of them was actually defined...

Change-Id: I496140e43cf8ff8a5712394023d98516aaf21adc