add vuex store to vue app

src/main.js

@@ -1,7 +1,11 @@
 import Vue from 'vue';
 import router from './router';
+import store from './store';
 
-new Vue({
+const app = new Vue({
   router,
+  store,
   render: h => h('router-view'),
-}).$mount('#app');
+});
+
+app.$mount('#app');

src/store.js

@@ -0,0 +1,11 @@
+import Vue from 'vue';
+import Vuex from 'vuex';
+
+Vue.use(Vuex);
+
+const store = new Vuex.Store({
+  state: {
+  },
+});
+
+export default store;