404 and style change a bit

static/style.css

@@ -27,7 +27,7 @@ a:hover {
   margin: 0;
   padding: 0;
   display: flex;
-  background-color: #333333;
+  background-color: #111111;
   position: fixed;
   top: 0;
   left: 0;
@@ -49,7 +49,7 @@ a:hover {
 }
 
 .navbar li a:hover {
-  background-color: #111111;
+  background-color: #222222;
 }
 
 main {

templates/404.html

@@ -1,6 +1,6 @@
 {% extends 'base.html' %}
 {% block content %}
-<h1>Oops! Page Not Found (404)</h1>
+<h1>oops</h1>
 <p>The page you are looking for does not exist.</p>
 <p>Return to home page by click the home button on the top left of this page</p>
 {% endblock %}