change grid’s `clearfix` instead of clearfix in mixin.less
change grid’s `clearfix` instead of clearfix in mixin.less

MicroComputerClub/mcc_lt,motoso/rin,DesignYama/designyama.github.io,tbaba/tatsurooo,nakano-lt/004,MicroComputerClub/mcc_lt,motoso/rin,nickwanhere/rin,designless/rin,pentapod/c90,pentapod/c90,sanographix/rin,nakano-lt/004,nickwanhere/rin,tbaba/tatsurooo,designless/rin,sanographix/rin,DesignYama/designyama.github.io