弹出不起作用

Question

<li>
  <button type="button" class="btn" data-toggle="modal" data-target="#myModal">settings</button>
  <div class="modal fade" id="myModal" role="dialog">
    <div class="modal-dialog modal-sm">
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">Settings</h4> 
        </div>
        <div class="modal-body">
          <form action="#" class="form-horizontal" role="form" method="post">
            <div class="form-group">
              <label for="setting_name" class="col-lg-4 control-label">Setting Name</label>
              <div class="col-lg-8">
                <input type="text" maxlength="25" class="form-control" id="setting_name" name="setting_name" placeholder="Setting Name" required>
              </div>
            </div>
            <div class="form-group">
              <label for="setting_value" class="col-lg-4 control-label">Setting Value</label>
              <div class="col-lg-8">
                <input type="int" maxlength="10" class="form-control" id="setting_value" name="setting_value" placeholder="Setting Value" required>
              </div>
            </div>
            <div class="form-group">
              <div class="col-lg-offset-2 col-lg-6">
                <button type="submit" class="btn btn-warning">Send</button>
              </div>
            </div>
            <div class="form-group">
              <div class="col-lg-offset-2 col-lg-10">
                <button type="submit" data-dismiss="modal" class="btn btn-info">Close</button>
              </div>
            </div>
          </form>
        </div>
      </div>
    </div>
  </div>

每当我开火时，弹出窗口都不起作用。只是屏幕褪色，没有任何反应，我必须刷新它。