Reduce excessive empty space across all website pages

Adjust vertical padding and margins on various pages and the footer to decrease whitespace, improving layout density on both desktop and mobile.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 23852c00-4779-460a-9e0c-d09fee4b6c92
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Replit-Commit-Event-Id: 1a3c4949-1987-4937-a1b8-d66e3d8b8bb1
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client/src/pages/impressum.tsx

@@ -10,7 +10,7 @@ export default function ImpressumPage() {
     <div className="min-h-screen bg-background">
       <Header />
       <PageSideAds />
-      <main className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
+      <main className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-4">
         <div className="flex items-center gap-3 mb-8">
           <Scale className="w-7 h-7 text-primary" />
           <h1 className="text-3xl font-bold text-foreground" data-testid="text-impressum-title">