style(web): Seiten auf Mosaik-Muster umgestellt

Einheitliche Seitenkoepfe mit Modul-Kachel, Knopf- und Linkklassen
statt gelber Schrift, Karten ohne harte Rahmen, Tabellenkoepfe ohne
Grossbuchstaben, Marktplatz mit Fluent-Reitern, Filterpillen und
Kachel-Karten, Einstellungs-/Verwaltungsnavigation mit Auswahlpille,
leere Zustaende mit Symbol im Kreis, Proxmox ohne leuchtende Schatten.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

apps/web/src/app/(portal)/modules/domaincheck/components/DomainInput.tsx

@@ -33,7 +33,7 @@ export function DomainInput({ onSubmit, isLoading }: DomainInputProps) {
       <button
         type="submit"
         disabled={isLoading || !domain.trim()}
-        className="inline-flex items-center justify-center rounded-md bg-primary px-4 py-2 text-sm font-medium text-primary-foreground hover:opacity-90 transition-opacity disabled:pointer-events-none disabled:opacity-50"
+        className="btn btn-primary disabled:pointer-events-none"
       >
         {isLoading ? t('checking') : t('checkButton')}
       </button>

apps/web/src/app/(portal)/modules/domaincheck/components/ResultList.tsx

@@ -33,7 +33,7 @@ export function ResultList({ results }: ResultListProps) {
 
       {suggestions.length > 0 && (
         <div className="space-y-2">
-          <p className="text-xs font-medium text-muted-foreground uppercase tracking-wide">
+          <p className="text-xs font-medium text-muted-foreground">
             {t('suggestions')}
           </p>
           {suggestions.map((result) => (

apps/web/src/app/(portal)/modules/domaincheck/page.tsx

@@ -1,5 +1,6 @@
 'use client';
 
+import { PageHeader } from '@/components/layout/page-header';
 import { useTranslations } from 'next-intl';
 import { useState } from 'react';
 import { type DomainCheckResult, checkDomainAction } from './actions';
@@ -37,17 +38,11 @@ export default function DomaincheckPage() {
   };
 
   return (
-    <div className="mx-auto max-w-2xl space-y-6 p-6">
-      {/* Header */}
-      <div>
-        <h1 className="text-2xl font-bold tracking-tight">{t('title')}</h1>
-        <p className="text-sm text-muted-foreground mt-1">
-          {t('description')}
-        </p>
-      </div>
+    <div className="mx-auto max-w-2xl space-y-6 p-3 sm:p-6">
+      <PageHeader moduleSlug="domaincheck" title={t('title')} description={t('description')} />
 
       {/* Card panel (per D-05a) */}
-      <div className="rounded-lg border border-border bg-card p-6 shadow-sm space-y-4">
+      <div className="rounded-lg bg-card dark:border dark:border-border p-6 shadow-sm space-y-4">
         {/* Domain input */}
         <DomainInput onSubmit={handleSubmit} isLoading={isLoading} />