refactored styles to extract btn

app/ui/okDialog.js

@@ -5,10 +5,7 @@ module.exports = function(message) {
     return html`
       <send-ok-dialog class="flex flex-col max-w-xs p-4">
         <div class="text-center m-8 leading-normal">${message}</div>
-        <button
-          class="rounded bg-blue hover\:bg-blue-dark focus\:bg-blue-darker cursor-pointer text-center text-white py-2 px-6 h-12 w-full flex flex-no-shrink items-center justify-center font-semibold"
-          onclick="${close}"
-        >
+        <button class="btn rounded w-full flex-no-shrink" onclick="${close}">
           ${state.translate('okButton')}
         </button>
       </send-ok-dialog>