<!DOCTYPE html>
<link rel="help" href="https://drafts.csswg.org/css-gaps-1/#outset">
<link rel="author" title="Sam Davis Omekara Jr." href="mailto:samomekarajr@microsoft.com">
<style>
  body {
    margin: 0px;
  }

  .grid-container {
    display: grid;
    grid-gap: 10px;
    grid-template-columns: 100px 100px 100px;
    height: 320px;
  }

  .item {
    background: gray;
    opacity: 0.5;
  }

  .row-gap {
    width: 320px;
    height: 0px;
    border-bottom: solid 5px red;
  }

  .row-gap1 {
    position