JavaScriptでToastを表示させる

下記JavaScriptを定義した上で, showToast("hogehoge", 5);とすれば, 5秒間だけトーストスタイルで"hogehoge"が表示される

Toast.js

////
//// Show Toast Style Message From JavaScript.
///////////////////////////////////////////////////////////////////////////////////////
var timer;
var toastElement;

///
/// Method For Show Toast Style Message
/// @param message	Meesage String 
/// @param second	Second For Message Showing. Or Default Setting Time(=3second)
///
function showToast( message, second ) {
	second = second || 3;
	var divElement = document.createElement("div");
	var spanElement = document.createElement("span");
	setToastStyle(divElement, spanElement);
	spanElement.innerText = message;
	divElement.appendChild(spanElement);

	document.body.appendChild(divElement);

	// Adjust Message Show Place
	divElement.style.position = "absolute";
	divElement.style.left = (window.innerWidth/2 - divElement.offsetWidth/2) + "px";
	divElement.style.top = (window.innerHeight*3/4) + "px";
	toastElement = divElement;

	var from = 0;
	var distance = 0.8;
	var duration = 1000;
	var begin = new Date() - 0;
	var id = setInterval(function() {
			var time = new Date() - begin;
			var current = easing(time, from, distance, duration);
			if( time > duration ) {
				clearInterval(id);
				current = from + distance;

				// Remove Toast From Display
				timer = setTimeout("removeToast()", second * 1000);
			} else {
				toastElement.style.opacity = current;
				toastElement.style.transparent = current;
			}
	}, 10);
}

///
/// Style Setting For Toast Style Message.
///
function setToastStyle(divElement, spanElement) {
	divElement.style.padding = "10px 70px";
	spanElement.style.padding = "3px";
	divElement.style.backgroundColor = "#f0e68c";
	divElement.style.borderRadius = "1em";
	divElement.style.border = "1px solid red";

	divElement.style.opacity = 0;
	divElement.style.transparent = 0;
	
}

///
/// Remove Toast From Display
///
function removeToast() {
	if( toastElement ) {
		var from = 0.8;
		var distance = -0.8;
		var duration = 1000;
		var begin = new Date() - 0;
		var id = setInterval(function() {
				var time = new Date() - begin;
				var current = easing(time, from, distance, duration);
				if( time > duration ) {
					clearInterval(id);
					current = from + distance;
					document.body.removeChild(toastElement);
					toastElement = null;
				} else {
					toastElement.style.opacity = current;
					toastElement.style.transparent = current;
				}
		}, 100);
	}
}

function easing( time, from, distance, duration ) {
	return distance * time / duration + from;
}