Add feature of CSS opacity property

README.md

@@ -38,6 +38,7 @@ To get started with Selection.js, download the [Script](https://github.com/prate
     speak:true,
     backgroundColor: 'crimson',
     iconColor: '#fff',
+    opacity: 0.8,
   }).init();
 </script>
 ```

index.html

@@ -53,18 +53,17 @@ <h2 class="header text-center">Basic Usage</h2>
 			</div>
 			<div class="col-md-6">
 				<h2 class="header text-center">Advanced Usage</h2>
-				<script src="https://gist.github.com/prateekkalra/a858930c0955576892a8aa400a18b472.js"></script>
+				<script src="https://gist.github.com/s1r-J/295e56b7614259335a5807c8ef7221b2.js"></script>
 			</div>
 		</div>
 
 	</div>
 
 
 </body>
-<script type="text/javascript" src="index.js"></script>
 <script type="text/javascript" src="selection.js"></script>
 <script type="text/javascript">
-	var selection = new Selection();
+  var selection = new Selection();
   selection.config({
     facebook: true,
     twitter: true,
@@ -74,6 +73,7 @@ <h2 class="header text-center">Advanced Usage</h2>
     translate:true,
     backgroundColor: 'crimson',
     iconColor: '#fff',
+    opacity: 0.8,
   }).init();
 </script>
 </html>

selection.js

@@ -114,6 +114,7 @@ const Selection = (function() {
     let iconsize = 24 + buttonmargin;
     let top = 0;
     let left = 0;
+    let opacity = 1;
 
     function facebookButton() {
       const fbbtn = new Button(facebookConfig.icon, function() {
@@ -229,6 +230,7 @@ const Selection = (function() {
         'px;' +
         'transition:all .2s ease-in-out;' +
         'box-shadow: 0 14px 28px rgba(0,0,0,0.25), 0 10px 10px rgba(0,0,0,0.22);' +
+        'opacity:' + opacity + ';' +
         'z-index:99999;';
 
       div.appendChild(_icons.icons);
@@ -308,6 +310,7 @@ const Selection = (function() {
 
       bgcolor = options.backgroundColor || '#333';
       iconcolor = options.iconColor || '#fff';
+      opacity = options.opacity || 1;
       return this;
     }