Make notifications bell more readable

customize.dist/src/less2/include/toolbar.less

@@ -399,6 +399,9 @@
 
         button {
             .toolbar_button;
+            &.cp-notifications-bell {
+                color: @cryptpad_text_col;
+            }
         }
 
         .cp-toolbar-limit {

www/common/toolbar.js

@@ -1049,7 +1049,7 @@ MessengerUI, Messages) {
         var $newPadBlock = UIElements.createDropdown(dropdownConfig);
         var $button = $newPadBlock.find('button');
         $button.attr('title', Messages.notificationsPage);
-        $button.addClass('fa fa-bell-o');
+        $button.addClass('fa fa-bell-o cp-notifications-bell');
         var $n = $button.find('.cp-dropdown-button-title').hide();
         var $empty = $(div).find('.cp-notifications-empty');