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<div class="grid stripes-background">
  <div>grid item1</div>
  <div>grid item2</div>
</div>

<div class="flex stripes-background">
  <div>flex item1</div>
  <div>flex item2</div>
</div>

.stripes-background {
  background-image: linear-gradient(45deg, #000 25%, transparent 25%, transparent 50%, #000 50%, #000 75%, transparent 75%, #fff);
  background-size: 50px 50px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
}

.flex {
  background-color: yellow;
  display: flex;
}

.grid div, .flex div {
  border: 1px solid black;
  width: 50%;
  background-color: rgba(0, 256, 0, 0.7);
}