var imageHeight;
var distance = 180;
var logoDistance;


Event.observe(window, 'load', function() {

	imageHeight = $('sidebar-img').getHeight();

	if(imageHeight != 0) {
		
		if(imageHeight < distance) {
			logoDistance = distance - imageHeight;
		} else {
			logoDistance = 0;
		}
		$('logo').setStyle('margin-top: ' + logoDistance + 'px;');
		
	}
	
});