Minimal Grid

grid.css

.grid {
  overflow: hidden;
  margin-left: -1.4rem;
}

.grid-col {
  float: left;
  padding-left: 1.4rem;
  -webkit-box-sizing: border-box;
     -moz-box-sizing: border-box;
          box-sizing: border-box;
}

.grid-col_3of12 { width: 25%; }
.grid-col_4of12 { width: 33.3333%; }
.grid-col_6of12 { width: 50%; }
.grid-col_8of12 { width: 66.6666%; }
.grid-col_9of12 { width: 75%; }