Underline active tab
<p>I'd like to underline the active tab with a thick line and make it a teal color.  When the tab is inactive, then the underline should disappear.  What I have so far is an underline under each tab but am not sure how to turn it off/on depending on if it's active or not.</p>

<pre><code>                &lt;Style TargetType="{x:Type TabItem}"&gt;
                    &lt;Style.Triggers&gt;
                        &lt;Trigger Property="IsSelected" Value="True"&gt;
                            &lt;Setter Property="Foreground" Value="#48637E" /&gt;
                        &lt;/Trigger&gt;
                        &lt;Trigger Property="IsSelected" Value="False"&gt;
                            &lt;Setter Property="Foreground" Value="#B4B4B4" /&gt;
                        &lt;/Trigger&gt;
                    &lt;/Style.Triggers&gt;
                &lt;/Style&gt;


            &lt;TabItem&gt;
                &lt;TabItem.Header&gt;
                    &lt;StackPanel &gt;
                        &lt;TextBlock Text=" FirstTab" FontFamily="Arial" FontSize="14" FontWeight="Bold" /&gt;
                        &lt;TextBlock Text="___________"  Foreground="#00A79D" /&gt;
                    &lt;/StackPanel&gt;
                &lt;/TabItem.Header&gt;
            &lt;/TabItem&gt;
</code></pre>

<p>Thanks</p>