Resolve differences in the way that different browsers supply information about the viewport and the position of the document and cursor within the viewport by using this static object.
These are set to the values at the time that the page first loads and do not reflect any changes if the visitor changes their screen resolution or resizes their browser while viewing the page.
$B.sWidth - the width of the screen in pixels
$B.sHeight - the height of the screen in pixels
$B.width - the width of the browser viewport in pixels
$B.height - the height of the browser viewport in pixels
These will retrieve the current values at the time of the event that you use to trigger calling them.
$B.left() - the current horizontal scroll distance in pixels
$B.top() - the current vertical scroll distance in pixels
$B.mouseX() - the horizontal position of the mouse from the left of the page in pixels at the time the last event was triggered
$B.mouseY() - the vertical position of the mouse from the top of the page in pixels at the time the last event was triggered