// 定义最小宽度
	function move(x,y){
		$(this).css("background-position",x+"px " +y +"px");
	}
	$.fn.minWidth = function(width){
	$(this).each(function(){
		var $this = $(this);
		var resize = function(){
			if($(window).width() < width){
				$this.width(width);
			} else {
				$this.width("100%");
			}
		};
		resize();
		$(window).resize(resize);
			});
		};