Forbid body drag

HTML

JS

document.body.ondrag = function () { return false; }

see some **document.body**'s **drag*** attributes.

CSS

.unselectable {
   -moz-user-select: -moz-none;
   -khtml-user-select: none;
   -webkit-user-select: none;

   /*
     Introduced in IE 10.
     See http://ie.microsoft.com/testdrive/HTML5/msUserSelect/
   */
   -ms-user-select: none;
   user-select: none;
}