diff --git a/public/app.js b/public/app.js
index 00b9fd2..1fc115c 100755
--- a/public/app.js
+++ b/public/app.js
@@ -21,11 +21,13 @@ const loginBtn = document.getElementById("login-btn");
 const loginSubmit = document.getElementById("login-submit");
 const loginMsg = document.getElementById("login-msg");
 const nav = document.getElementById("services");
+const estopBtn = document.getElementById("emergency-stop");
 
 const usernameInput = document.getElementById("username");
 const passwordInput = document.getElementById("password");
 
 let loggedIn = false;
+let armedPollInterval = null;
 
 // ===========================
 // Login anzeigen
@@ -57,6 +59,8 @@ function switchToLogout() {
 // ===========================
 function performLocalLogout() {
     loggedIn = false;
+    stopArmedPolling();
+    estopBtn.style.display = "none";
     iframe.src = "";
     iframe.style.display = "none";
     nav.innerHTML = "";
@@ -64,6 +68,46 @@ function performLocalLogout() {
     switchToLogin();
 }
 
+// ===========================
+// Armed-Status prüfen
+// ===========================
+async function updateArmedStatus() {
+    try {
+        const r = await fetch('https://robotDriver.server.schooltech.ch/api/power-status');
+        if (r.ok) {
+            const data = await r.json();
+            estopBtn.style.display = data.armed ? "block" : "none";
+        } else {
+            estopBtn.style.display = "none";
+        }
+    } catch (e) {
+        estopBtn.style.display = "none";
+    }
+}
+
+function startArmedPolling() {
+    updateArmedStatus();
+    armedPollInterval = setInterval(updateArmedStatus, 5000);
+}
+
+function stopArmedPolling() {
+    if (armedPollInterval) {
+        clearInterval(armedPollInterval);
+        armedPollInterval = null;
+    }
+}
+
+// ===========================
+// Emergency Stop
+// ===========================
+estopBtn.addEventListener("click", async () => {
+    try {
+        await fetch('https://robotDriver.server.schooltech.ch/api/emergency-stop', { method: 'POST' });
+    } catch (e) {
+        console.error('E-Stop request failed:', e);
+    }
+});
+
 // ===========================
 // Login-Logik
 // ===========================
@@ -84,6 +128,7 @@ async function doLogin() {
             loginMsg.textContent = "";
             setupServiceButtons();
             switchToLogout();
+            startArmedPolling();
         } else {
             loginMsg.textContent = "Login fehlgeschlagen";
         }
@@ -156,6 +201,7 @@ function openService(svc) {
             loggedIn = true;
             setupServiceButtons();
             switchToLogout();
+            startArmedPolling();
         } else {
             switchToLogin();
         }
diff --git a/public/index.html b/public/index.html
index d1d024c..8bf96d3 100755
--- a/public/index.html
+++ b/public/index.html
@@ -10,8 +10,31 @@
 <header id="header">
   <div class="logo">schooltech</div>
   <nav id="services"></nav>
-  <div class="user">
-    <button id="login-btn">Login</button>
+  <div class="right-actions">
+    <div id="emergency-stop" title="Emergency Stop">
+      <svg width="78" height="78" viewBox="0 0 78 78" xmlns="http://www.w3.org/2000/svg">
+        <defs>
+          <radialGradient id="redGrad" cx="38%" cy="32%" r="62%">
+            <stop offset="0%"   stop-color="#ff5555"/>
+            <stop offset="65%"  stop-color="#cc0000"/>
+            <stop offset="100%" stop-color="#880000"/>
+          </radialGradient>
+          <!-- Textpfad: Radius 34, weit aussen im gelben Ring -->
+          <path id="estop-textarc" d="M 9,39 A 30,30 0 0,0 69,39"/>
+        </defs>
+        <!-- Gelber Aussenring (10% grösser: r=36 statt ~33) -->
+        <circle cx="39" cy="39" r="36" fill="#FFD700" stroke="#C8960A" stroke-width="1.5"/>
+        <!-- Roter Knopf -->
+        <circle cx="39" cy="39" r="21" fill="url(#redGrad)" stroke="#660000" stroke-width="2"/>
+        <!-- Gebogener Text, weiter aussen, mit Wortabstand -->
+        <text font-size="7.5" fill="#1a1000" font-weight="bold" font-family="system-ui,sans-serif" letter-spacing="0.3" word-spacing="5">
+          <textPath href="#estop-textarc" startOffset="50%" text-anchor="middle">EMERGENCY STOP</textPath>
+        </text>
+      </svg>
+    </div>
+    <div class="user">
+      <button id="login-btn">Login</button>
+    </div>
   </div>
 </header>
 
diff --git a/public/style.css b/public/style.css
index b5dcb9d..70cf131 100755
--- a/public/style.css
+++ b/public/style.css
@@ -10,24 +10,51 @@ body {
 
 
 header {
-  height: 48px; 
+  height: 48px;
   display: flex;
   align-items: center;
   gap: 16px;
   padding: 0 20px;
   backdrop-filter: blur(6px);
   background: rgba(0,0,0,0.35);
-
-  /* NEU – hochwertiger Shadow */
   box-shadow: 0 4px 12px rgba(0,0,0,0.35);
+  overflow: visible;
+  position: relative;
+  z-index: 100;
 }
 
 .logo {
   font-weight: bold;
 }
 
+.right-actions {
+  margin-left: auto;
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
 .user {
-  margin-left: auto; /* ⬅️ Login/Logout nach rechts */
+  display: flex;
+  align-items: center;
+}
+
+#emergency-stop {
+  display: none;
+  position: relative;
+  width: 78px;
+  height: 78px;
+  cursor: pointer;
+  flex-shrink: 0;
+  transition: transform 0.1s ease;
+}
+
+#emergency-stop:hover svg {
+  filter: brightness(1.12);
+}
+
+#emergency-stop:active {
+  transform: scale(0.93);
 }
 
 nav button {