planning#404: change navitem type and root-link,

tweak style

docusaurus.config.js

@@ -42,8 +42,8 @@ module.exports = {
       // },
       items: [
         {
-          to: '/',
-          html: '<img src="/icons/caret-left-fluent.svg" alt="Zurück" />',
+          type: 'html',
+          value: `<a href="/"><img src="${baseUrl}icons/caret-left-fluent.svg" alt="Zurück" /></a>`,
           position: 'left',
           className: 'fitko-navbar-icon--back',
         },

src/css/style.scss

@@ -84,7 +84,7 @@ img {
   padding: 0;
   position: absolute;
   left: -14px;
-  top: 14px;
+  top: 13px;
 }
 
 .fitko-navbar-icon--back.hidden {