change code structure

src/views/Main/index.vue

@@ -0,0 +1,25 @@
+<template>
+  <div>
+    <main-menu />
+    <keep-alive include="Editor">
+      <router-view id="main-view" />
+    </keep-alive>
+  </div>
+</template>
+
+<script>
+import MainMenu from './MainMenu'
+import '@/assets/styles/scrollbars.css'
+
+export default {
+  name: 'Main',
+  components: { MainMenu }
+}
+</script>
+<style scoped>
+#main-view {
+  margin-top: 68px;
+  height: calc(100vh - 68px);
+  overflow-y: auto;
+}
+</style>