JavaScript信息提示框

(function(window){
    var realwall = {
        sayclue : function(message, cluewidth) {
			var scrollPos = 0; 
			if (window.pageYOffset) {
				scrollPos = window.pageYOffset; 
			} else if (document.compatMode && document.compatMode != 'BackCompat') {
				scrollPos = document.documentElement.scrollTop;
			} else if (document.body) { 
				scrollPos = document.body.scrollTop;
			}
			var left = 400,top = scrollPos + 400;
			var str = '<div class="clue" style="position: absolute; left: '
				+ left + 'px; top:'
				+ top
				+'px; padding: 10px 0px 10px 10px; border: solid 4px #8a4; width:'
				+ cluewidth
				+ 'px; background-color:#ecf8ff; filter:alpha(opcity=85); text-align:center;">'
				+ message + '</div>';
			$('body').append(str);
			setTimeout(function() {
				$('.clue').fadeOut("slow");
				$('.clue').remove();
			}, 2000);
		}
    };
    window.realwall = realwall;
})(window);