56 is latest stable, though I think 57 is rolling out. From quick search, 57 seems to be the one that has added support for CSS Grid (which is very new). So it'

56 is latest stable, though I think 57 is rolling out. From quick search, 57 seems to be the one that has added support for CSS Grid (which is very new). So it's not so much that your browser is outdated, but rather that this feature is fresh out of the oven.