If you grok Stylus, nib is pretty self-documenting. Looking at the vendor support mixins, https://github.com/visionmedia/nib/blob/master/lib/nib/vendor.styl ht

If you grok Stylus, nib is pretty self-documenting. Looking at the vendor support mixins, https://github.com/visionmedia/nib/blob/master/lib/nib/vendor.styl https://github.com/visionmedia/nib/blob/master/lib/nib/vendo..., border-radius doesn't employ any specific MS techniques. You can take a look at the opacity mixin in the same file, which does use a MS filter.