title: why css not apply on form in angular js
body: <p><img src="https://i.stack.imgur.com/Ey1qy.png" alt="enter image description here"></p>
  
  <p>I apply css in form it should apply when my form is invalid .I also write <strong>important</strong> but nothing happen .In other words I make a dynamic form from json ,Now I need to validate that form .so I apply css which is not working.why I am apply css because some one suggest that in this <a href="https://stackoverflow.com/questions/25313167/how-to-validate-form-using-pristine-and-dirty-in-angular.can">how to validate form using $pristine and $dirty in angular?</a> you please why it is not apply 
  here is my plunker 
  <a href="http://plnkr.co/edit/ECLvOstUxq5tIDrYicF2?p=preview" rel="nofollow noreferrer">http://plnkr.co/edit/ECLvOstUxq5tIDrYicF2?p=preview</a></p>
  
  <pre><code>/* Styles go here */
  
  
  .ng-invalid {
    border :1px solid red !important;
  }
  .ng-pristine {
      border :1px solid blue !important;
  
  }
  .ng-pristine {
      border :1px solid blue !important;
  
  }
  </code></pre>
  
  <p>Updated plunker 
  <a href="http://plnkr.co/edit/ECLvOstUxq5tIDrYicF2?p=preview" rel="nofollow noreferrer">http://plnkr.co/edit/ECLvOstUxq5tIDrYicF2?p=preview</a>
  I press <strong>login</strong> button nothing happen</p>