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/dkv-fleet/page.tsx

@@ -4,6 +4,7 @@ import { useCallback, useState } from 'react';
 import { useTranslations } from 'next-intl';
 import { useParams } from 'next/navigation';
 import Link from 'next/link';
+import { PageHeader } from '@/components/layout/page-header';
 import { checkNow, type DkvHistoryEntry } from '@/lib/dkv-api';
 import { InvoiceHistoryTable } from './components/InvoiceHistoryTable';
 import { ExportFileList } from './components/ExportFileList';
@@ -75,51 +76,47 @@ export default function DkvFleetPage() {
   };
 
   return (
-    <div className="mx-auto max-w-5xl space-y-6 p-6">
-      {/* Page Header Row */}
-      <div className="flex items-start justify-between gap-4">
-        <div>
-          <h1 className="text-2xl font-semibold tracking-tight">
-            {t('pageTitle')}
-          </h1>
-          <p className="mt-1 text-sm text-muted-foreground">
-            {lastChecked
-              ? t('lastChecked', { time: formatLastChecked(lastChecked) })
-              : t('neverChecked')}
-          </p>
-        </div>
-
-        {/* Einstellungen-Link */}
-        <Link
-          href={`${basePath}/settings`}
-          className="rounded border border-border px-3 py-2 text-sm text-muted-foreground transition-colors hover:bg-muted hover:text-foreground"
-          title={t('settingsTitle')}
-        >
-          <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
+    <div className="mx-auto max-w-5xl space-y-6 p-3 sm:p-6">
+      {/* Seitenkopf (Design „Mosaik“): App-Kachel, Titel, Stand; Aktionen rechts */}
+      <PageHeader
+        moduleSlug="dkv-fleet"
+        title={t('pageTitle')}
+        description={
+          lastChecked
+            ? t('lastChecked', { time: formatLastChecked(lastChecked) })
+            : t('neverChecked')
+        }
+        actions={
+          <>
+            <Link
+              href={`${basePath}/settings`}
+              className="btn btn-secondary btn-icon"
+              title={t('settingsTitle')}
+              aria-label={t('settingsTitle')}
+            >
+              <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
             <circle cx="12" cy="12" r="3" />
             <path d="M19.4 15a1.65 1.65 0 0 0 .33 1.82l.06.06a2 2 0 0 1-2.83 2.83l-.06-.06a1.65 1.65 0 0 0-1.82-.33 1.65 1.65 0 0 0-1 1.51V21a2 2 0 0 1-4 0v-.09A1.65 1.65 0 0 0 9 19.4a1.65 1.65 0 0 0-1.82.33l-.06.06a2 2 0 0 1-2.83-2.83l.06-.06A1.65 1.65 0 0 0 4.68 15a1.65 1.65 0 0 0-1.51-1H3a2 2 0 0 1 0-4h.09A1.65 1.65 0 0 0 4.6 9a1.65 1.65 0 0 0-.33-1.82l-.06-.06a2 2 0 0 1 2.83-2.83l.06.06A1.65 1.65 0 0 0 9 4.68a1.65 1.65 0 0 0 1-1.51V3a2 2 0 0 1 4 0v.09a1.65 1.65 0 0 0 1 1.51 1.65 1.65 0 0 0 1.82-.33l.06-.06a2 2 0 0 1 2.83 2.83l-.06.06A1.65 1.65 0 0 0 19.4 9a1.65 1.65 0 0 0 1.51 1H21a2 2 0 0 1 0 4h-.09a1.65 1.65 0 0 0-1.51 1z" />
           </svg>
-        </Link>
-
-        {/* "Jetzt prüfen" button per 07-UI-SPEC button states */}
-        <button
-          type="button"
-          onClick={handleCheckNow}
-          disabled={isChecking}
-          className={`rounded bg-primary px-4 py-2 text-sm font-medium text-primary-foreground transition-colors hover:bg-primary/90 flex items-center${
-            isChecking ? ' opacity-80 cursor-not-allowed' : ''
-          }`}
-        >
-          {isChecking ? (
-            <>
-              <SpinnerIcon />
-              {t('checking')}
-            </>
-          ) : (
-            t('checkNow')
-          )}
-        </button>
-      </div>
+            </Link>
+            <button
+              type="button"
+              onClick={handleCheckNow}
+              disabled={isChecking}
+              className="btn btn-primary"
+            >
+              {isChecking ? (
+                <>
+                  <SpinnerIcon />
+                  {t('checking')}
+                </>
+              ) : (
+                t('checkNow')
+              )}
+            </button>
+          </>
+        }
+      />
 
       {/* Error banner — conditional per UI-SPEC */}
       {pollError && (