diff --git a/app/static/css/style.css b/app/static/css/style.css
index 9929b71..e7b0c7b 100644
--- a/app/static/css/style.css
+++ b/app/static/css/style.css
@@ -295,6 +295,22 @@ p {
   display: inline-flex;
   align-items: center;
   gap: 14px;
+  min-width: 0;
+}
+
+.brand__mark {
+  width: 58px;
+  height: 58px;
+  flex: 0 0 58px;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  overflow: hidden;
+  border-radius: 20px;
+  background: radial-gradient(circle at 50% 42%, rgba(112, 207, 255, 0.38), rgba(37, 99, 235, 0.08));
+  box-shadow:
+    0 18px 38px rgba(37, 99, 235, 0.18),
+    inset 0 0 0 1px rgba(255, 255, 255, 0.24);
 }
 
 .brand strong {
@@ -308,8 +324,37 @@ p {
 }
 
 .brand__logo {
-  width: 48px;
-  height: 48px;
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
+}
+
+.brand--public .brand__mark {
+  width: 64px;
+  height: 64px;
+  flex-basis: 64px;
+  border-radius: 22px;
+}
+
+.hero-card__brand-mark {
+  width: 108px;
+  height: 108px;
+  margin-bottom: 18px;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  overflow: hidden;
+  border-radius: 32px;
+  background: radial-gradient(circle at 50% 40%, rgba(112, 207, 255, 0.42), rgba(37, 99, 235, 0.12));
+  box-shadow:
+    0 22px 48px rgba(37, 99, 235, 0.22),
+    inset 0 0 0 1px rgba(255, 255, 255, 0.26);
+}
+
+.hero-card__brand-mark img {
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
 }
 
 .flash-stack {
@@ -1281,6 +1326,25 @@ p {
 }
 
 @media (max-width: 640px) {
+  .brand {
+    gap: 12px;
+  }
+
+  .brand__mark {
+    width: 50px;
+    height: 50px;
+    flex-basis: 50px;
+    border-radius: 18px;
+  }
+
+  .brand--public .brand__mark,
+  .hero-card__brand-mark {
+    width: 88px;
+    height: 88px;
+    flex-basis: 88px;
+    border-radius: 28px;
+  }
+
   .task-card {
     gap: 14px;
     padding: 18px;
diff --git a/app/static/images/logo-mark.png b/app/static/images/logo-mark.png
new file mode 100644
index 0000000..484ed54
Binary files /dev/null and b/app/static/images/logo-mark.png differ
diff --git a/app/static/service-worker.js b/app/static/service-worker.js
index 142e92c..cde8f2a 100644
--- a/app/static/service-worker.js
+++ b/app/static/service-worker.js
@@ -1,8 +1,8 @@
-const CACHE_NAME = "putzliga-shell-v2";
+const CACHE_NAME = "putzliga-shell-v3";
 const ASSETS = [
   "/static/css/style.css",
   "/static/js/app.js",
-  "/static/images/logo.svg",
+  "/static/images/logo-mark.png",
   "/static/images/pwa-icon-192.png",
   "/static/images/pwa-icon-512.png"
 ];
diff --git a/app/templates/auth/login.html b/app/templates/auth/login.html
index 15dbf32..0f51402 100644
--- a/app/templates/auth/login.html
+++ b/app/templates/auth/login.html
@@ -3,6 +3,9 @@
 {% block content %}
   <section class="auth-layout">
     <div class="hero-card hero-card--brand">
+      <div class="hero-card__brand-mark">
+        <img src="{{ url_for('static', filename='images/logo-mark.png') }}" alt="Putzliga Logo">
+      </div>
       <p class="eyebrow">Leichtgewichtige Haushalts-App</p>
       <h2>Putzliga bringt Punkte, Rhythmus und ein bisschen Liga-Stimmung in den Alltag.</h2>
       <p>Mehrere Nutzer, wiederkehrende Aufgaben, Monats-Highscore, Archiv, Kalender und PWA-Pushs in einer bewusst schlanken Flask-App.</p>
diff --git a/app/templates/auth/register.html b/app/templates/auth/register.html
index 1c9c05b..ce238b8 100644
--- a/app/templates/auth/register.html
+++ b/app/templates/auth/register.html
@@ -3,6 +3,9 @@
 {% block content %}
   <section class="auth-layout">
     <div class="hero-card hero-card--brand">
+      <div class="hero-card__brand-mark">
+        <img src="{{ url_for('static', filename='images/logo-mark.png') }}" alt="Putzliga Logo">
+      </div>
       <p class="eyebrow">Gemeinsam sauberer</p>
       <h2>Erstelle dein Konto und steig direkt in die Liga ein.</h2>
       <p>Nach dem Login landest du sofort bei „Meine Aufgaben“ und kannst Aufgaben anlegen, verteilen und Punkte sammeln.</p>
@@ -39,4 +42,3 @@
     </section>
   </section>
 {% endblock %}
-
diff --git a/app/templates/base.html b/app/templates/base.html
index fdc2935..a05f942 100644
--- a/app/templates/base.html
+++ b/app/templates/base.html
@@ -26,7 +26,9 @@
     {% if current_user.is_authenticated %}
       <aside class="sidebar">
         <a class="brand" href="{{ url_for('tasks.my_tasks') }}">
-          <img src="{{ url_for('static', filename='images/logo.svg') }}" alt="Putzliga Logo" class="brand__logo">
+          <span class="brand__mark">
+            <img src="{{ url_for('static', filename='images/logo-mark.png') }}" alt="Putzliga Logo" class="brand__logo">
+          </span>
           <div>
             <strong>Putzliga</strong>
             <span>Haushalt mit Punktestand</span>
@@ -68,7 +70,9 @@
           </a>
         {% else %}
           <a class="brand brand--public" href="{{ url_for('auth.login') }}">
-            <img src="{{ url_for('static', filename='images/logo.svg') }}" alt="Putzliga Logo" class="brand__logo">
+            <span class="brand__mark">
+              <img src="{{ url_for('static', filename='images/logo-mark.png') }}" alt="Putzliga Logo" class="brand__logo">
+            </span>
             <div>
               <strong>Putzliga</strong>
               <span>Haushaltsaufgaben mit Liga-Gefühl</span>