Simple grids. Infinite ❤️ & all credit to Chris Coyier. (https://css-tricks.com/dont-overthink-it-grids/)

grids.css

.grid { width: auto; }

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

[class*='col-'] {
  float: left;
  padding-right: 1.5em;
  margin-top: 0;
}

[class*='col-']:last-of-type { padding-right: 0; }

.col-1-2 { width: 50%; }
.col-1-3 { width: 33.33%; }
.col-2-3 { width: 66.66%; }
.col-1-4 { width: 25%; }

@media (max-width: 40em) {
    [class*='col-'] { width: 100%; }
}