Fix 404.html page

docs/404.html

@@ -3,22 +3,15 @@ layout: default
 title: Error 404
 ---
 
-  <div class="content-wrapper">
-    <section class="content-header">
-      <div class="container-fluid">
-        <div class="row mb-2">
-        </div>
-      </div>
-    </section>
-
+  <div class="content-wrapper pt-5">
     <section class="content">
       <div class="error-page">
-        <h2 class="headline text-warning"> 404</h2>
+        <h2 class="headline text-warning">404</h2>
         <div class="error-content">
           <h3><i class="fas fa-exclamation-triangle text-warning"></i> Oops! Page not found.</h3>
           <p>
             We could not find the page you were looking for.
-            Meanwhile, you may <a href="{{ site.baseurl }}{% link index.md %}">return to index</a>.
+            Meanwhile, you may <a href="{% link index.md %}">return to index</a>.
           </p>
         </div>
       </div>