与bootstrap具有相同高度的Divs

<div class="container">
  <div class="row">
    <div class="col">
      <div class="content">Content 1</div>
    </div>
    <div class="col">
      <div class="content">Content 2</div>
    </div>
    <div class="col">
      <div class="content">Content 3</div>
    </div>
  </div>
</div>

.container {
  display: flex;
}

.col {
  flex: 1;
}

.content {
  height: 100%;
  background-color: #f2f2f2;
}

<div class="container">
  <div class="col">
    <div class="content">Content 1</div>
  </div>
  <div class="col">
    <div class="content">Content 2</div>
  </div>
  <div class="col">
    <div class="content">Content 3</div>
  </div>
</div>

var cols = document.getElementsByClassName('col');
var maxHeight = 0;

for (var i = 0; i < cols.length; i++) {
  var height = cols[i].offsetHeight;
  if (height > maxHeight) {
    maxHeight = height;
  }
}

for (var i = 0; i < cols.length; i++) {
  cols[i].style.height = maxHeight + 'px';
}