title: How to change constraints programmatically that is added from storyboard?
body: <p>I have one screen. It will display like below</p>
  
  <p><a href="https://i.stack.imgur.com/LWaCz.png" rel="noreferrer"><img src="https://i.stack.imgur.com/LWaCz.png" alt="enter image description here"></a></p>
  
  <p>Now When User clicked I have an Account and Password(button) it will display like below</p>
  
  <p><a href="https://i.stack.imgur.com/96qo9.png" rel="noreferrer"><img src="https://i.stack.imgur.com/96qo9.png" alt="enter image description here"></a></p>
  
  <p>I want to move both views accordingly
  I added constraints using storyboard.Now need to change constraints from programming..</p>