使用bootstrap对齐4个字段

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<script src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/5.5.0/js/bootstrap.min.js"></script>

<div class="container">
  <form>
    <div class="row">
      <div class="col-md-3">
        <label for="field1">字段1：</label>
        <input type="text" class="form-control" id="field1">
      </div>
      <div class="col-md-3">
        <label for="field2">字段2：</label>
        <input type="text" class="form-control" id="field2">
      </div>
      <div class="col-md-3">
        <label for="field3">字段3：</label>
        <input type="text" class="form-control" id="field3">
      </div>
      <div class="col-md-3">
        <label for="field4">字段4：</label>
        <input type="text" class="form-control" id="field4">
      </div>
    </div>
  </form>
</div>