🎨 Add theme support

- Move root (var) style properties to `/assets/css/themes.scss`
- Improve mobile navigation
- Create section component for the collapsable sections.
- Create logo component, so color can be changed.

- Add settings page
- Add option to select theme color
- Add option to select theme background
- Add option to enable/disable multi-colored frames.

- Add settings to VueX Store
- Persist VueX store in LocalStorage.

package.json

@@ -11,8 +11,9 @@
     "generate": "nuxt generate"
   },
   "dependencies": {
+    "@nuxtjs/pwa": "^3.0.0-0",
     "nuxt": "^2.0.0",
-    "@nuxtjs/pwa": "^3.0.0-0"
+    "vuex-persist": "^2.0.1"
   },
   "devDependencies": {
     "node-sass": "^4.12.0",