function catchMouse(e) {
	var DocRef;
	var Mouse_X;
	var Mouse_Y;

	if(e) { 
		Mouse_X = e.pageX;
		Mouse_Y = e.pageY;
	} else {
		Mouse_X = event.clientX;
		Mouse_Y = event.clientY;

		if( document.documentElement && document.documentElement.clientWidth)
		DocRef = document.documentElement;
		else
		DocRef = document.body; 

		Mouse_X += DocRef.scrollLeft;
		Mouse_Y += DocRef.scrollTop;
	}
	
	// document.getElementById('posMouse').innerHTML = "X : "+Mouse_X+"<br>Y : "+Mouse_Y ;
	// return(Mouse_X);
	
	// relative X :
	windowWidth = document.body.clientWidth;
	absoluteX = Mouse_X;
	relativeX = absoluteX - windowWidth/2;
	
	return(relativeX);

}

function cssModifier(e) {
	windowWidth = document.body.clientWidth;

	relativeMouse_X = catchMouse(e);
	centredImg_X = (windowWidth/2)-725;
	leftMargin_img = centredImg_X-relativeMouse_X/5;
	
	document.getElementById("posMouse").style.marginLeft = leftMargin_img/3 + "px";
	document.getElementById("posMouse2").style.marginLeft  = leftMargin_img+200 + "px";
}