Fix dark mode: sync dark class to html element for Tailwind

index.html

@@ -613,6 +613,7 @@ function dashboard() {
     toggleDark() {
       this.dark = !this.dark;
       localStorage.setItem('dark', String(this.dark));
+      document.documentElement.classList.toggle('dark', this.dark);
     },
 
     portAccessLabel(port, inv) {
@@ -650,6 +651,7 @@ function dashboard() {
     },
 
     init() {
+      document.documentElement.classList.toggle('dark', this.dark);
       // Each service has: external (public domain/ip), lan (192.168.x), ts (tailscale 100.x)
       // Fields left undefined = not applicable
       this.publicServices = [