feat(timepicker): small style change for timepicker

public/less/timepicker.less

@@ -16,7 +16,6 @@
 
 li.gf-timepicker-open a {
   background-color: @grafanaPanelBackground;
-  .box-shadow(0px 10px 0px @grafanaPanelBackground);
 }
 
 .gf-timepicker-absolute-section {
@@ -35,8 +34,8 @@ li.gf-timepicker-open a {
 }
 
 .gf-timepicker-utc {
-  background-color: @blueDark;
-  color: @white;
+  background-color: @grafanaTargetFuncBackground;
+  color: @orange;
   font-size: 75%;
   padding: 3px;
   border-radius: 2px;