This is the DoubleClick for Publishers (DFP) responsive ads example. DFP does not provide responsive ad features like Google Adsense so you can use this coding.

Put this code in your header file.

<script type="text/javascript">
  var googletag = googletag || {};
  googletag.cmd = googletag.cmd || [];
  (function() {
    var gads = document.createElement("script");
    gads.async = true;
    gads.type = "text/javascript";
    var useSSL = "https:" == document.location.protocol;
    gads.src = (useSSL ? "https:" : "http:") +
      "//www.googletagservices.com/tag/js/gpt.js";
    var node = document.getElementsByTagName("script")[0];
    node.parentNode.insertBefore(gads, node);
  })();
</script>

Replace "XXXXXXXXX" value with your DFP publisher ID and put this code in your header file.

<script type="text/javascript">
	googletag.cmd.push(function() {
	
  var mappingLeaderboard = googletag.sizeMapping().
		addSize([1024, 768 ], [728, 90]).
		addSize([500, 500 ], [468, 60]).
		addSize([1, 1 ], [320, 50]).
		build();
		
  var mappingLeaderboard2 = googletag.sizeMapping().
  		addSize([1024, 768 ], [970, 90]).
		addSize([800, 600 ], [728, 90]).
		addSize([500, 500 ], [468, 60]).
		addSize([1, 1 ], [320, 50]).
		build();
		
  var mappingLeaderboard3 = googletag.sizeMapping().
  		addSize([1024, 768 ], [468, 60]).
		addSize([800, 600 ], [468, 60]).
		addSize([500, 500 ], [468, 60]).
		addSize([1, 1 ], [300, 250]).
		build();

  var mappingBox = googletag.sizeMapping().
		addSize([1024, 768 ], [336, 280]).
		addSize([800, 600 ], [336, 280]).
		addSize([500, 500 ], [300, 250]).
		addSize([1, 1 ], [250, 250]).
		build();

	googletag.defineSlot("/XXXXXXXXX/Responsive_ads", [[320, 50], [468, 60], [970, 90], [728, 90]], "div-gpt-ad-1499850832266-0").defineSizeMapping(mappingLeaderboard2).addService(googletag.pubads());
	
	googletag.defineSlot("/XXXXXXXXX/mappingLeaderboard", [[320, 50], [468, 60], [728, 90]], "div-gpt-ad-1499851829170-0").defineSizeMapping(mappingLeaderboard).addService(googletag.pubads());

	googletag.defineSlot("/XXXXXXXXX/mappingBox", [[336, 280], [250, 250], [300, 250]], "div-gpt-ad-1499851906927-0").defineSizeMapping(mappingBox).addService(googletag.pubads());
	
	googletag.defineSlot("/XXXXXXXXX/mappingLeaderboard2", [[468, 60], [300, 250]], "div-gpt-ad-1499863451422-0").defineSizeMapping(mappingLeaderboard3).addService(googletag.pubads());

	googletag.pubads().enableSingleRequest();

	googletag.enableServices();

});

</script>

And put this code where you want to show the responsive ads.

<div id="div-gpt-ad-1499851906927-0"><script type="text/javascript">googletag.cmd.push(function() { googletag.display("div-gpt-ad-1499851906927-0"); });</script></div>

That's all, hope it helps you guys.
GoodLuck.