diff --git a/internal/service/static/main.js b/internal/service/static/main.js
index 3d1c142..194bed6 100644
--- a/internal/service/static/main.js
+++ b/internal/service/static/main.js
@@ -32,6 +32,7 @@ class Odidere {
     this.isScrollPending = false;
     this.isStopPending = false;
     this.mediaRecorder = null;
+    this.wakeLock = null;
 
     // Auto-scroll: enabled by default, disabled when user scrolls up,
     // re-enabled when they scroll back to bottom or send a new message.
@@ -88,6 +89,7 @@ class Odidere {
     }
     this.#stopCurrentAudio();
     this.currentController?.abort();
+    this.#releaseWakeLock();
   }
 
   /**
@@ -124,6 +126,7 @@ class Odidere {
     this.#bindEvents();
     this.#fetchVoices();
     this.#fetchModels();
+    this.#initWakeLock();
   }
 
   /**
@@ -213,6 +216,9 @@ class Odidere {
     this.$saveSystemMessage.addEventListener('click', () =>
       this.#saveSystemMessage(),
     );
+
+    // Wake lock: reacquire on visibility change
+    this.document.addEventListener('visibilitychange', () => this.#handleVisibilityChange());
   }
 
   /**
@@ -548,6 +554,7 @@ class Odidere {
     this.audioChunks = [];
     this.mediaRecorder.start();
     this.#setRecordingState(true);
+    this.#acquireWakeLock();
   }
 
   /**
@@ -1069,6 +1076,12 @@ class Odidere {
       this.isStopPending = false;
       this.$send.classList.remove('pending');
     }
+
+    if (loading) {
+      this.#acquireWakeLock();
+    } else {
+      this.#releaseWakeLock();
+    }
   }
 
   /**
@@ -1681,6 +1694,57 @@ class Odidere {
       console.error('failed to copy:', e);
     }
   }
+
+  // ====================
+  // WAKE LOCK
+  // ====================
+  /**
+   * #initWakeLock performs feature detection for the Screen Wake Lock API.
+   */
+  #initWakeLock() {
+    if (!('wakeLock' in navigator)) {
+      console.debug('Screen Wake Lock API not supported');
+    }
+  }
+
+  /**
+   * #acquireWakeLock requests a screen wake lock. Idempotent.
+   */
+  async #acquireWakeLock() {
+    if (this.wakeLock) return;
+    if (!('wakeLock' in navigator)) return;
+
+    try {
+      this.wakeLock = await navigator.wakeLock.request('screen');
+    } catch (e) {
+      console.debug('wake lock acquire failed:', e);
+    }
+  }
+
+  /**
+   * #releaseWakeLock releases the active wake lock. Idempotent.
+   */
+  async #releaseWakeLock() {
+    if (!this.wakeLock) return;
+
+    try {
+      await this.wakeLock.release();
+    } catch (e) {
+      console.debug('wake lock release failed:', e);
+    }
+
+    this.wakeLock = null;
+  }
+
+  /**
+   * #handleVisibilityChange reacquires the wake lock when the tab becomes
+   * visible, if the app is currently active (recording or processing).
+   */
+  #handleVisibilityChange() {
+    if (this.document.visibilityState !== 'visible') return;
+    if (!this.isRecording && !this.isProcessing) return;
+    this.#acquireWakeLock();
+  }
 }
 
 // Initialize