如何将第二个宽度为100%的两个div并排放置？

<div class="container">
  <div class="div1">Div 1</div>
  <div class="div2">Div 2</div>
</div>

.container {
  display: flex;
}

.div1, .div2 {
  flex: 1;
}

<div class="container">
  <div class="div1">Div 1</div>
  <div class="div2">Div 2</div>
</div>

.container {
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.div1, .div2 {
  width: 100%;
}