Andy Bell's auto grid CSS without media queries

auto-grid.css

/*
  19 Sept 2019
  See "Keeping it simple with CSS that scales" 
  at https://hankchizljaw.com/wrote/keeping-it-simple-with-css-that-scales/
 */

.auto-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(16rem, 1fr));
  grid-gap: 1rem;
}

.auto-grid > * {
  max-width: 25rem;
  margin-left: auto;
  margin-right: auto;
}

.auto-grid > * + * {
  margin-top: 1rem;
}

@supports (display: grid) {
  .auto-grid > * {
    max-width: unset;
    margin: 0;
  }
}