title: Md-select underline color change
body: <p>I have tried changing the color of <code>md-select</code> underline with the following css:</p>
  
  <pre><code>md-input-container &gt; md-select  {
      border-color: rgba(13, 148, 74, 0.82);
  }
  </code></pre>
  
  <p>but it doesn't work.</p>
  
  <p>Here is the html which contains the md-select which I want to customize:</p>
  
  <pre><code>&lt;md-input-container&gt;
      &lt;label&gt;Items&lt;/label&gt;
      &lt;md-select ng-model="selectedItem" md-selected-text="getSelectedText()" ng-required="true"&gt;
         &lt;md-optgroup label="items"&gt;
            &lt;md-option ng-value="item" ng-repeat="item in items"&gt;{{item}}&lt;/md-option&gt;
         &lt;/md-optgroup&gt;
      &lt;/md-select&gt;
  &lt;/md-input-container&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/soyKe.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/soyKe.jpg" alt="enter image description here"></a></p>