var currentOffset = null; var maxOffset = null; var property = "left"; var rfa = null; if (window.requestAnimationFrame) { rfa = requestAnimationFrame; } else if (window.webkitRequestAnimationFrame) { rfa = webkitRequestAnimationFrame; } else if (window.msRequestAnimationFrame) { rfa = msRequestAnimationFrame; } else if (window.oRequestAnimationFrame) { rfa = oRequestAnimationFrame; } function animate(from, to, prop) { currentOffset = from; maxOffset = to; if (prop) { property = prop; } rfa(animateStep); } function animateStep() { if (currentOffset <= maxOffset) { document.getElementById("child").style[property] = currentOffset + "px"; currentOffset += 10; rfa(animateStep); } else { document.documentElement.removeAttribute("class"); } } function toAuto(prop) { if (prop) { property = prop; } rfa(setToAuto); } function setToAuto() { document.getElementById("child").style[property] = "auto"; document.documentElement.removeAttribute("class"); } function fromAuto(to, prop) { maxOffset = to; if (prop) { property = prop; } rfa(setFromAuto); } function setFromAuto() { document.getElementById("child").style[property] = maxOffset + "px"; document.documentElement.removeAttribute("class"); }