js+css3制作按键弹出钢琴键特效

敲击对应的键盘按钮看效果
window.onload = function(){
		var aP = document.getElementsByTagName("p");
		var aSpan = document.getElementsByTagName("span");
		var aKeyCode = [65,83,68,74,75,76];
		document.onkeydown = function(event){
			var event = event || window.event;
			for(var i=0; i0?Math.ceil(speed):Math.floor(speed);
				if(sAttribute=='opacity'){
					obj.style.filter='alpha(opacity:'+(cur+speed)+')'; //IE
					obj.style.opacity=(cur+speed)/100; //ff chrome
				}else{
					obj.style[sAttribute]=cur+speed+'px';
				}
				if(cur!=iTarget){
					bSwitch=false;
				}
			}
			if(bSwitch){
			  clearInterval(obj.timer);
			  if(fnEnd){
				fnEnd();
			  }
			}
		}, 30);
	}
	//获取飞行间样式
	function getStyle(obj,sAuttribute){
		var result = ""
		if(window.getComputedStyle){
			result = window.getComputedStyle(obj,false)[sAuttribute];
		}else{
			resule = obj.currentStyle[sAuttribute];
		}
		return result;
	}