Change "a" tag for "button" tag

Author: davidangarita1

src/components/modebar/modebar.js

@@ -146,8 +146,9 @@ proto.createGroup = function() {
  */
 proto.createButton = function(config) {
     var _this = this;
-    var button = document.createElement('a');
+    var button = document.createElement('button');
 
+    button.setAttribute('type', 'button');
     button.setAttribute('tabindex', '0');
     button.setAttribute('rel', 'tooltip');
     button.className = 'modebar-btn';

src/css/_modebar.scss

@@ -40,7 +40,8 @@
     cursor: pointer;
     line-height: normal;
     box-sizing: border-box;
-
+    border: none;
+    background: transparent;
     svg {
         position: relative;
         top: 2px;