小编Gra*_*ith的帖子

.grid-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  grid-template-rows: 1fr 1fr;
  grid-template-areas: "leftCol rightTop" "leftCol rightBottom";
  height: 100vh;
}

.leftCol {
  grid-area: leftCol;
  background-color: pink;
  width: 100%;
  height: 100;
}

.rightBottom {
  grid-area: rightBottom;
  background-color: yellow;
  width: 100%;
  height: 100;
}

.rightTop {
  grid-area: rightTop;
  background-color: blue;
  width: 100%;
  height: 100;
}

<div class="grid-container">
  <div class="leftCol"></div>
  <div class="rightBottom"></div>
  <div class="rightTop"></div>
</div>