diff --git a/simulator/static/style.css b/simulator/static/style.css
index 68a082a..2626d8a 100644
--- a/simulator/static/style.css
+++ b/simulator/static/style.css
@@ -268,3 +268,27 @@ nav button {
     font-size: 1rem;
     color: #ccc;
 }
+
+
+.sleep-overlay {
+    position: fixed;
+    inset: 0;
+    background: #000;
+    color: #777;
+    z-index: 10000;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    font-size: 2rem;
+}
+
+.sleep-overlay.hidden {
+    display: none;
+}
+
+.sleep-overlay small {
+    margin-top: 10px;
+    font-size: 1rem;
+    color: #555;
+}
diff --git a/simulator/templates/index.html b/simulator/templates/index.html
index 8276763..20d256b 100644
--- a/simulator/templates/index.html
+++ b/simulator/templates/index.html
@@ -14,6 +14,11 @@
     </div>
 </div>
 
+<div id="sleepOverlay" class="sleep-overlay hidden" onclick="wakeScreen()">
+    <div>Screen Off</div>
+    <small>Tap to wake</small>
+</div>
+
 <div id="warningBanner" class="warning-banner hidden"></div>
 
 <main>
@@ -129,6 +134,7 @@
 let relayState = {};
 let activeAlarmKey = null;
 let acknowledgedAlarms = new Set();
+let screenWakeTimeout = null;
 
 let alarmConfig = {
     rear_seat_warning: 85,
@@ -289,6 +295,7 @@ async function loadStatus() {
     document.getElementById('sysWifi').textContent = data.network.wifi_enabled ? 'Enabled' : 'Disabled';
     document.getElementById('sysWifiOverride').textContent = data.network.wifi_override_active ? 'Active' : 'Inactive';
     document.getElementById('sysIgnition').textContent = data.vehicle.ignition_on ? 'ON' : 'OFF';
+    updateSleepOverlay(data.vehicle.ignition_on);
 
     checkAlarms(data);
 }
@@ -303,6 +310,33 @@ async function toggleRelay(name) {
     loadStatus();
 }
 
+function updateSleepOverlay(ignitionOn) {
+    const overlay = document.getElementById('sleepOverlay');
+
+    if (ignitionOn) {
+        overlay.classList.add('hidden');
+        return;
+    }
+
+    if (!screenWakeTimeout) {
+        overlay.classList.remove('hidden');
+    }
+}
+
+function wakeScreen() {
+    const overlay = document.getElementById('sleepOverlay');
+    overlay.classList.add('hidden');
+
+    if (screenWakeTimeout) {
+        clearTimeout(screenWakeTimeout);
+    }
+
+    screenWakeTimeout = setTimeout(() => {
+        screenWakeTimeout = null;
+        overlay.classList.remove('hidden');
+    }, 10000);
+}
+
 async function toggleIgnition() {
     await fetch('/vehicle/ignition', {
         method: 'POST',