fix: scroll-class check on load, hero null guard, JS syntax fix

public/js/haus-schleusingen.js

@@ -1,16 +1,23 @@
 document.addEventListener("DOMContentLoaded", function () {
   // Navbar scroll
   var navbar = document.getElementById("navbar");
-  window.addEventListener("scroll", function () {
+  function checkScroll() {
     if (window.scrollY > 60) navbar.classList.add("scrolled");
     else navbar.classList.remove("scrolled");
-  });
+  }
+  // Check immediately on load (for non-hero pages already scrolled)
+  checkScroll();
+  window.addEventListener("scroll", checkScroll);
 
-  // Hero animation on load
+  // Hero animation on load (only if hero elements exist)
+  var heroContent = document.getElementById("heroContent");
+  var heroBg = document.getElementById("heroBg");
+  if (heroContent || heroBg) {
     setTimeout(function () {
-    document.getElementById("heroContent").classList.add("visible");
-    document.getElementById("heroBg").classList.add("loaded");
+      if (heroContent) heroContent.classList.add("visible");
+      if (heroBg) heroBg.classList.add("loaded");
     }, 200);
+  }
 
   // Scroll animations via IntersectionObserver
   var animElements = document.querySelectorAll(".fact, [data-animate]");
@@ -177,7 +184,6 @@ document.addEventListener("DOMContentLoaded", function () {
 
   // Form submit is handled server-side by PHP – no JS intervention needed.
   // Success feedback is shown via #form-result after server redirect.
-  });
 });
 
 // Mobile hamburger menu (vanilla JS)