renderer: add global style in app.vue

src/renderer/App.vue

@@ -4,8 +4,12 @@
   </div>
 </template>
 
-<script>
-export default {
-  name: 'App'
-}
-</script>
+<style>
+  html {
+    overflow-y: auto !important
+  }
+  html, body {
+    width: 100%;
+    height: 100%
+  }
+</style>