title: How to change material stepper line style with labelPosition="bottom"
body: <p>I wont to create style like this:</p>
  
  <p><a href="https://i.stack.imgur.com/OYxth.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OYxth.png" alt="enter image description here"></a></p>
  
  <p>I tried to set style for all lines under edited steps, but there is lines outside of mat-step-headers.</p>
  
  <pre><code>::ng-deep .mat-horizontal-stepper-header {
      &amp;[ng-reflect-state='edit'] + .mat-stepper-horizontal-line {
                 border-top-width: 4px;
                 border-top-color: blue;
      }
  }
  </code></pre>
  
  <p>this is the result:</p>
  
  <p><a href="https://i.stack.imgur.com/BQHH3.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BQHH3.png" alt="enter image description here"></a></p>
  
  <p>So, how can i make it?</p>