1<html> 2 <head> 3 <style type="text/css"> 4 body { 5 overflow: hidden; 6 } 7 #a { 8 background-color: green; 9 width: 100px; 10 height: 1000px; 11 } 12 </style> 13 <script> 14 function allowScroll() 15 { 16 document.body.style.overflow = "auto"; 17 } 18 </script> 19 </head> 20<body> 21This page is not scrollable until allowScroll() is called. 22<div id="a"></div> 23</body> 24</html>