diff --git a/lib/fitie.js b/lib/fitie.js
index 4ccd4d9..96b3613 100644
--- a/lib/fitie.js
+++ b/lib/fitie.js
@@ -1,95 +1,97 @@
-this.fitie = function (node) {
-	// restrict to valid object-fit value
-	var objectFit = node.currentStyle ? node.currentStyle['object-fit'] : null;
+(function(){
+	function fitie(node) {
+		// restrict to valid object-fit value
+		var objectFit = node.currentStyle ? node.currentStyle['object-fit'] : null;
 
-	if (!objectFit || !/^(contain|cover|fill)$/.test(objectFit)) return;
+		if (!objectFit || !/^(contain|cover|fill)$/.test(objectFit)) return;
 
-	// prepare container styles
-	var outerWidth  = node.clientWidth;
-	var outerHeight = node.clientHeight;
-	var outerRatio  = outerWidth / outerHeight;
+		// prepare container styles
+		var outerWidth  = node.clientWidth;
+		var outerHeight = node.clientHeight;
+		var outerRatio  = outerWidth / outerHeight;
 
-	var name = node.nodeName.toLowerCase();
+		var name = node.nodeName.toLowerCase();
 
-	var setCSS = node.runtimeStyle;
-	var getCSS = node.currentStyle;
+		var setCSS = node.runtimeStyle;
+		var getCSS = node.currentStyle;
 
-	var addEventListener = node.addEventListener || node.attachEvent;
-	var removeEventListener = node.removeEventListener || node.detachEvent;
-	var on = node.addEventListener ? '' : 'on';
-	var img = name === 'img';
-	var type = img ? 'load' : 'loadedmetadata';
+		var addEventListener = node.addEventListener || node.attachEvent;
+		var removeEventListener = node.removeEventListener || node.detachEvent;
+		var on = node.addEventListener ? '' : 'on';
+		var img = name === 'img';
+		var type = img ? 'load' : 'loadedmetadata';
 
-	addEventListener.call(node, on + type, onload);
+		addEventListener.call(node, on + type, onload);
 
-	if (node.complete) onload();
+		if (node.complete) onload();
 
-	function onload() {
-		removeEventListener.call(node, on + type, onload);
+		function onload() {
+			removeEventListener.call(node, on + type, onload);
 
-		// prepare container styles
-		var imgCSS = {
-			boxSizing: 'content-box',
-			display:   'inline-block',
-			overflow:  'hidden'
-		};
+			// prepare container styles
+			var imgCSS = {
+				boxSizing: 'content-box',
+				display:   'inline-block',
+				overflow:  'hidden'
+			};
+
+			'backgroundColor backgroundImage borderColor borderStyle borderWidth bottom fontSize lineHeight height left opacity margin position right top visibility width'.replace(/\w+/g, function (key) {
+				imgCSS[key] = getCSS[key];
+			});
 
-		'backgroundColor backgroundImage borderColor borderStyle borderWidth bottom fontSize lineHeight height left opacity margin position right top visibility width'.replace(/\w+/g, function (key) {
-			imgCSS[key] = getCSS[key];
-		});
+			// prepare image styles
+			setCSS.border = setCSS.margin = setCSS.padding = 0;
+			setCSS.display = 'block';
+			setCSS.height = setCSS.width = 'auto';
+			setCSS.opacity = 1;
 
-		// prepare image styles
-		setCSS.border = setCSS.margin = setCSS.padding = 0;
-		setCSS.display = 'block';
-		setCSS.height = setCSS.width = 'auto';
-		setCSS.opacity = 1;
+			var innerWidth  = node.videoWidth || node.width;
+			var innerHeight = node.videoHeight || node.height;
+			var innerRatio  = innerWidth / innerHeight;
 
-		var innerWidth  = node.videoWidth || node.width;
-		var innerHeight = node.videoHeight || node.height;
-		var innerRatio  = innerWidth / innerHeight;
+			// style container
+			var imgx = document.createElement('object-fit');
 
-		// style container
-		var imgx = document.createElement('object-fit');
+			imgx.appendChild(node.parentNode.replaceChild(imgx, node));
 
-		imgx.appendChild(node.parentNode.replaceChild(imgx, node));
+			for (var key in imgCSS) imgx.runtimeStyle[key] = imgCSS[key];
 
-		for (var key in imgCSS) imgx.runtimeStyle[key] = imgCSS[key];
+			// style image
+			var newSize;
 
-		// style image
-		var newSize;
+			if (objectFit === 'fill') {
+				if (img) {
+					setCSS.width = outerWidth;
+					setCSS.height = outerHeight;
+				} else {
+					setCSS['-ms-transform-origin'] = '0% 0%';
+					setCSS['-ms-transform'] = 'scale(' + outerWidth / innerWidth + ',' + outerHeight / innerHeight + ')';
+				}
+			} else if (innerRatio < outerRatio ? objectFit === 'contain' : objectFit === 'cover') {
+				newSize = outerHeight * innerRatio;
 
-		if (objectFit === 'fill') {
-			if (img) {
-				setCSS.width = outerWidth;
-				setCSS.height = outerHeight;
+				setCSS.width  = Math.round(newSize) + 'px';
+				setCSS.height = outerHeight + 'px';
+				setCSS.marginLeft = Math.round((outerWidth - newSize) / 2) + 'px';
 			} else {
-				setCSS['-ms-transform-origin'] = '0% 0%';
-				setCSS['-ms-transform'] = 'scale(' + outerWidth / innerWidth + ',' + outerHeight / innerHeight + ')';
+				newSize = outerWidth / innerRatio;
+
+				setCSS.width  = outerWidth + 'px';
+				setCSS.height = Math.round(newSize) + 'px';
+				setCSS.marginTop = Math.round((outerHeight - newSize) / 2) + 'px';
 			}
-		} else if (innerRatio < outerRatio ? objectFit === 'contain' : objectFit === 'cover') {
-			newSize = outerHeight * innerRatio;
+		}
+	}
 
-			setCSS.width  = Math.round(newSize) + 'px';
-			setCSS.height = outerHeight + 'px';
-			setCSS.marginLeft = Math.round((outerWidth - newSize) / 2) + 'px';
-		} else {
-			newSize = outerWidth / innerRatio;
+	if (/MSIE|Trident/.test(navigator.userAgent)) {
+		if (document.body) {
+			var all = document.querySelectorAll('img,video');
+			var index = -1;
 
-			setCSS.width  = outerWidth + 'px';
-			setCSS.height = Math.round(newSize) + 'px';
-			setCSS.marginTop = Math.round((outerHeight - newSize) / 2) + 'px';
+			while (all[++index]) fitie(all[index]);
+		} else {
+			var _fitie = fitie;
+			setTimeout(_fitie);
 		}
 	}
-};
-this.fitie.init = function () {
-	if (document.body) {
-		var all = document.querySelectorAll('img,video');
-		var index = -1;
-
-		while (all[++index]) fitie(all[index]);
-	} else {
-		setTimeout(fitie.init);
-	}
-};
-
-if (/MSIE|Trident/.test(navigator.userAgent)) this.fitie.init();
+})();