Inline bootstrap form with labels above inputs

Question

How can I move down the search button at the same level with other textfields?

  <form>
       <div class="col-md-3 form-group">
         <label for="search">Title</label>
         <input type="text" name="search" id="search" class="form-control" />
       </div>
       <div class="col-md-2 form-group">
         <label for="created_at_gt">Created at from</label>
         <input type="text" name="created_at_gt" id="created_at_gt" class="form-control" />
       </div>
       <div class="col-md-2 form-group">
         <label for="created_at_lt">To</label>
         <input type="text" name="created_at_lt" id="created_at_lt" class="form-control" />
       </div>
       <div class="row align-center">
         <input type="submit" value="search" class="btn btn-primary" />
        </div>
    </form>

Answer 1

An easy way to fix is to add same structure as other input fields (also avoid to add additional CSS which may not cover all cases), for the label, use   as a placeholder.

<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<br><br><br><br><br><!-- ignore those br, just for stackoverflow full page view -->


<form>
  <div class="col-md-3 form-group">
    <label for="search">Title</label>
    <input type="text" name="search" id="search" class="form-control" />
  </div>
  <div class="col-md-2 form-group">
    <label for="created_at_gt">Created at from</label>
    <input type="text" name="created_at_gt" id="created_at_gt" class="form-control" />
  </div>
  <div class="col-md-2 form-group">
    <label for="created_at_lt">To</label>
    <input type="text" name="created_at_lt" id="created_at_lt" class="form-control" />
  </div>
  <div class="col-md-1 form-group align-center">
    <label for="created_at_lt">&nbsp;</label>
    <input type="submit" value="search" class="btn btn-primary form-control" />
  </div>
</form>

Answer 2

Another simple way would be to add the height of the label as a margin.

Make sure you go into fullpage view of the snippet to see the proper result:

.lowered {
  margin-top: 25px;
}

<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<br><br><br><br><br><!-- ignore those br, just for stackoverflow full page view -->


<form>
  <div class="col-md-3 form-group">
    <label for="search">Title</label>
    <input type="text" name="search" id="search" class="form-control" />
  </div>
  <div class="col-md-2 form-group">
    <label for="created_at_gt">Created at from</label>
    <input type="text" name="created_at_gt" id="created_at_gt" class="form-control" />
  </div>
  <div class="col-md-2 form-group">
    <label for="created_at_lt">To</label>
    <input type="text" name="created_at_lt" id="created_at_lt" class="form-control" />
  </div>
  <div class="col-md-2 form-group align-center">
    <input type="submit" value="search" class="btn btn-primary form-control lowered" />
  </div>
</form>