当超过父高度时，如何匹配同级高度

.parent {
  display: flex;
}

.child {
  flex: 1;
}

.parent {
  display: grid;
  grid-template-rows: 1fr;
}

.child {
  /* 可以设置其他样式 */
}

var parent = document.querySelector('.parent');
var children = document.querySelectorAll('.child');

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

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