function alertSize() {
      var myWidth = 0, myHeight = 0;
      if( typeof( window.innerWidth ) == 'number' ) {
      //Non-IE
      myWidth = window.innerWidth;
      myHeight = window.innerHeight;
      } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
      //IE 6+ in 'standards compliant mode'
      myWidth = document.documentElement.clientWidth;
      myHeight = document.documentElement.clientHeight;
      } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
      //IE 4 compatible
      myWidth = document.body.clientWidth;
      myHeight = document.body.clientHeight;
      }
      //window.alert( 'Width = ' + myWidth + ' // Height = ' + myHeight );
      return myHeight
   }

//create onDomReady Event
window.onDomReady = DomReady;

//Setup the event
function DomReady(fn)
{
   //W3C
   if(document.addEventListener)
   {
      document.addEventListener("DOMContentLoaded", fn, false);
   }
   //IE
   else
   {
      document.onreadystatechange = function(){readyState(fn)}
   }
}

//IE execute function
function readyState(fn)
{
   //dom is ready for interaction
   if(document.readyState == "interactive")
   {
      fn();
   }
}

//execute as soon as DOM is loaded
window.onDomReady(onReady);

//do on ready
function onReady()
{
   myheight = document.body.offsetHeight;
   minheight = alertSize();
   if (minheight > myheight)
   {
      setheight = minheight - 178;
      document.getElementById('seccion').style.height = setheight+'px';
   }
}