Super simple flexbox grid

grid.css

.row {
    display: flex;
    justify-content: space-between;
}
.col20 { width: 18.999%; } //20% columns
.col30 { width: 28.999%; } //30% columns
.col40 { width: 38.999%; } //40% columns
.col50 { width: 48.999%; } //50% columns
.col60 { width: 58.999%; } //60% columns
.col70 { width: 68.999%; } //70% columns
.col80 { width: 78.999%; } //80% columns