$main = $("body"); $body = $(".page1"); $cloud1 = $(".cloud1"); $cloud2 = $(".cloud2"); mainwidth = $main.outerwidth(); var $main = $cloud = mainwidth = null; var offset1 = 450; var offset2 = 0; var offsetbg = 0; $(document).ready( function () { $main = $("body"); $body = $(".page1"); $cloud1 = $(".cloud1"); $cloud2 = $(".cloud2"); mainwidth = $main.outerwidth(); } ); /// 飘动 setinterval(function flutter() { if (offset1 >= mainwidth) { offset1 = -580; } if (offset2 >= mainwidth) { offset2 = -580; } offset1 += 1.1; offset2 += 1; $cloud1.css("background-position", offset1 + "px 30px") $cloud2.css("background-position", offset2 + "px 340px") }, 70); setinterval(function bg() { if (offsetbg >= mainwidth) { offsetbg = -580; } offsetbg += 0.6; $body.css("background-position", -offsetbg + "px 0") }, 90 );