Purifycss and ">" css operator

Hi, does Purifycss remove lines with ">" css operator ?

I have this code on my project (from zurb/foundation) :

.grid-margin-x > .cell {...}

and i never used '.grid-margin-x', but i used '.cell'. After purify, the previous css rule still present.

purify-css : 1.2.5 node : 8.11.3