Fix #1658, focused button styles now override

RELEASE-NOTES.md

@@ -12,6 +12,7 @@
 **Bugs**
 
 - **Button** - Fixes formatting for `disabled button` inside `ui buttons`
+- **Button** - ``ui vertical basic buttons` now have dividers in default theme
 - **API** - Fixed bug where API would query resource immediately when specifying `on: false`
 - **API** - Fixed bug where `$.api('get xhr')` was not correctly returning xhr promise
 - *Sticky** - Fixes issue with container size not being set explicitly on rail due to improper method renaming

src/definitions/elements/button.less

@@ -84,9 +84,9 @@
 
 .ui.button:focus {
   background-color: @focusBackgroundColor;
-  background-image: @focusBackgroundImage;
-  box-shadow: @focusBoxShadow;
   color: @focusColor;
+  background-image: @focusBackgroundImage !important;
+  box-shadow: @focusBoxShadow !important;
 }
 
 .ui.button:focus .icon {