title: locking screen orientation on mobile browser
body: <p>I create a web page(chrome &amp; safari) for mobiles (iphone &amp; android), I want to lock the screen orientation in portrait mode.</p>
  
  <p>Unlike mobile apps,there is no manifest file and activity as it a web page.</p>
  
  <p>How to lock the orientation in mobiles using technologies (css/javascript/bootstrap/jquery) or any other?</p>