title: How to change the angular material mat stepper label color?
body: <p>I am currently trying to apply the mat stepper functionality in my application i am going through the example 
  from material.angular.io i am trying to apply similarly as shown in the example,</p>
  
  <p><a href="https://stackblitz.com/angular/vmqlalbjanq?file=app%2Fstepper-overview-example.html" rel="nofollow noreferrer">https://stackblitz.com/angular/vmqlalbjanq?file=app%2Fstepper-overview-example.html</a></p>
  
  <p>here in this example there are 3 labels 1) Fill out your name 2) Fill out your address and 3) done</p>
  
  <p>in each labels there are inputs like in Fill out your name label you have to fill <strong>last name</strong> and <strong>First name</strong> which
  is required and if you do not fill the input it appears in red color. Now i want the label to also appear in red color
  if i do not fill the input can someone tell me how to do it.</p>