title: How to make a radial reaction?
body: <p><a href="http://material-design.storage.googleapis.com/publish/v_2/material_ext_publish/0B0NGgBg38lWWMXpyWDRDWDJpeDA/animation-responsiveinteraction-materialresponse-030202_PointOfOrigin_DO_001.webm" rel="nofollow noreferrer">Here</a>, after button touch, it draws a circle under it. How to implent this?</p>
  
  <p><a href="https://i.stack.imgur.com/D81Za.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/D81Za.png" alt="enter image description here"></a></p>