Don't overthink it grids by Chris Coyier

grid

.grid {
	display: block;
}

.grid:after {
	content: 	" ";
	display: 	table;
	clear: 		both;
}


[class*='col-'] {
	float: 		left;
}

.col-1-1 { width: 100%; }

.col-1-2 { width: 50%; }

.col-1-3 { width: 33.333%; }
.col-2-3 { width: 66.666%; }

.col-1-4 { width: 25%; }
.col-2-4 { width: 50%; }
.col-3-4 { width: 75%; }

.col-1-5 { width: 20%; }
.col-2-5 { width: 40%; }
.col-3-5 { width: 60%; }
.col-4-5 { width: 80%; }

.col-1-7 { width: 14.2857%; }
.col-2-7 { width: 28.5714%; }
.col-3-7 { width: 42.8571%; }
.col-4-7 { width: 57.1428%; }
.col-5-7 { width: 71.4285%; }
.col-6-7 { width: 85.7142%; }

.col-1-8 { width: 12.5%; }
.col-3-8 { width: 37.5%; }
.col-5-8 { width: 62.5%; }
.col-7-8 { width: 87.5%; }

.col-1-10 { width: 10%; }
.col-3-10 { width: 30%; }
.col-7-10 { width: 70%; }
.col-9-10 { width: 90%; }