Add notice to the top (#923)

Author: egeakman

src/components/header/header.astro

@@ -7,7 +7,15 @@ import HeaderLogo from "./header-logo.astro";
 const links = JSON.parse(await fs.readFile("./src/data/links.json", "utf-8"));
 ---
 
-<header class="p-6 flex items-center relative z-40">
+<a
+  href="https://europython.eu/"
+  class="text-center px-2 bg-secondary text-white font-bold fixed top-0 w-full h-[40px] z-50 flex items-center justify-center"
+>
+  This is the website for an older EuroPython. Looking for the latest
+  EuroPython? Click here!
+</a>
+
+<header class="p-6 flex items-center relative z-40 top-10">
   <input
     type="checkbox"
     name="mobile-controls"