feat(popover): Make the popover menus customizable.

css/_popover.scss

     top: -25px;
     width: 100%;
 }
+
+.popover {
+    background-color: $popoverBg;
+    border-radius: 3px;
+    margin: -16px -24px;
+    padding: 16px 24px;
+}

css/_popup_menu.scss

 .popupmenu {
     min-width: 75px;
     text-align: left;
-    padding: 0;
+    padding: 0px;
+    width: 150px;
     white-space: nowrap;
 
     &__item {
         list-style-type: none;
         height: 35px;
-
-        &:hover {
-            background-color: rgba(9, 30, 66, 0.04);
-        }
     }
 
     // Link Appearance
         width: 100%;
         cursor: pointer;
         padding: 0 5px;
+        color: $popupMenuColor;
+
+        &:hover {
+            background-color: $popupMenuHoverBackground;
+            color: $popupMenuHoverColor;
+        }
 
         &.disabled {
             pointer-events: none;
                 top: 50%;
                 transform: translate(0, -50%);
                 width: 100%;
+
+                &::-webkit-slider-runnable-track {
+                    background-color: $popupSliderColor;
+                }
+
+                &::-moz-range-track {
+                    background-color: $popupSliderColor;
+                }
+
+                &::-ms-fill-lower {
+                    background-color: $popupSliderColor;
+                }
             }
         }
     }
  * InlineDialogs.
  */
 ul.popupmenu {
-    margin: -15px;
+    margin: -16px -24px;
 }
 
 span.remotevideomenu:hover ul.popupmenu, ul.popupmenu:hover {

css/themes/_light.scss

 $feedbackCancelFontColor: #333;
 
 // Popover colors
-$popoverBg: #000;
-$popoverFontColor: #ffffff;
-$popupMenuSelectedItemBackground: rgba(256, 256, 256, .2);
+$popoverBg: initial;
+$popoverFontColor: #ffffff !important;
+$popupMenuColor: #ffffff !important;
+$popupMenuHoverColor: #ffffff !important;
+$popupMenuHoverBackground: rgba(255, 255, 255, 0.1);
+$popupSliderColor: #0376da;
 
 // Toolbar
 $secondaryToolbarBg: rgba(0, 0, 0, 0.5);