/**************************************************************
 *
 * [mouseaction.js] toggle image at mouse actions
 *                           for KDDI Research Institute Inc.
 *           initial at 2008.05.16 by Blow Line Inc. rev.1.00
 * @author : hiroyu-n@blowline.co.jp
**************************************************************/
function tglBgImg(src){
	var srcStyle = src.style.backgroundPosition;
	if(srcStyle.indexOf("top")>-1 || srcStyle=="" || src.style['background-position']=="50% 0%"){
		src.style.backgroundPosition = "center bottom";
	}else if(srcStyle.indexOf("bottom")>-1 || src.style['background-position']=="50% 100%"){
		src.style.backgroundPosition = "center top";
	}
}