Hi there,
Most of those are warnings as the validator doesn’t recognize vendor prefixes for CSS3 – don’t worry about those.
Then you have some from a couple Jetpack plugins – but none of those are critical at all. Jetpack is also developed by WordPress, so those are some pretty great developers.
The GP errors are:
Parse Error @-ms-viewport {width: auto;}
Property zoom doesn't exist : 1
The first one is to make sure the grid system works using IE (ms – microsoft).
The zoom property is also for old versions of IE.
I wouldn’t worry too much about any of these π