diff --git a/src/lib/components/chrome/SplashScreen.svelte b/src/lib/components/chrome/SplashScreen.svelte
index fad48ec..05e5415 100644
--- a/src/lib/components/chrome/SplashScreen.svelte
+++ b/src/lib/components/chrome/SplashScreen.svelte
@@ -49,6 +49,7 @@
     notConfigured?: boolean
     showCards?:     boolean
     showFps?:       boolean
+    showDevOverlay?: boolean
     pinLen?:        number
     pinCorrect?:    string
     onReady?:       () => void
@@ -60,7 +61,7 @@
 
   let {
     mode = 'loading', ringFull = false, failed = false,
-    notConfigured = false, showCards = true, showFps = false,
+    notConfigured = false, showCards = true, showFps = false, showDevOverlay = false,
     pinLen = 4, pinCorrect = '',
     onReady, onUnlock, onRetry, onBypass, onDismiss,
   }: Props = $props()
@@ -464,7 +465,7 @@
     {/if}
   {/if}
 
-  {#if isDev && mode === 'idle' && devMetrics}
+  {#if isDev && mode === 'idle' && devMetrics && showDevOverlay}
     <div class="dev-overlay">
       <span class="dev-title">canvas · idle splash</span>
       <div class="dev-grid">
diff --git a/src/lib/components/settings/sections/DevToolsSettings.svelte b/src/lib/components/settings/sections/DevToolsSettings.svelte
index 9733bbe..b13b4c8 100644
--- a/src/lib/components/settings/sections/DevToolsSettings.svelte
+++ b/src/lib/components/settings/sections/DevToolsSettings.svelte
@@ -102,10 +102,10 @@
   }
 
   function triggerSplash() {
-    if (appState.idleSplash) return
+    if (appState.devSplash) return
     splashTriggered = true
     setTimeout(() => splashTriggered = false, 200)
-    appState.idleSplash = true
+    appState.devSplash = true
   }
 
   async function testWindowsHello() {
diff --git a/src/lib/state/app.svelte.ts b/src/lib/state/app.svelte.ts
index 8e4e1f3..2f302d1 100644
--- a/src/lib/state/app.svelte.ts
+++ b/src/lib/state/app.svelte.ts
@@ -36,6 +36,7 @@ export const appState = $state({
   toasts:        [] as unknown[],
   appDir:        '',
   idleSplash:    false,
+  devSplash:     false,
 })
 
 export function setSettingsOpen(next: boolean)        { app.setSettingsOpen(next) }
diff --git a/src/routes/+layout.svelte b/src/routes/+layout.svelte
index 3db14b5..d16a939 100644
--- a/src/routes/+layout.svelte
+++ b/src/routes/+layout.svelte
@@ -142,20 +142,38 @@
     if (appState.status === 'booting') splashDismissed = false
   })
 
-  let idleSplashLocked = false
-
-  function showIdleSplash() {
-    if (idleSplashLocked || appState.idleSplash) return
-    appState.idleSplash = true
-  }
+  let idleTimer:       ReturnType<typeof setTimeout> | null = null
+  let idleDismissLock = false
 
   function onIdleDismiss() {
-    if (idleSplashLocked) return
-    idleSplashLocked = true
+    if (idleDismissLock) return
+    idleDismissLock = true
     appState.idleSplash = false
-    setTimeout(() => { idleSplashLocked = false }, 400)
+    setTimeout(() => { idleDismissLock = false }, 400)
   }
 
+  function armIdleTimer() {
+    if (idleTimer !== null) clearTimeout(idleTimer)
+    const mins = settingsState.settings.idleTimeoutMin ?? 5
+    if (mins <= 0) return
+    idleTimer = setTimeout(() => {
+      if (appState.status === 'ready' && !appState.idleSplash) appState.idleSplash = true
+    }, mins * 60_000)
+  }
+
+  $effect(() => {
+    if (appState.status !== 'ready') return
+
+    const events = ['mousemove', 'mousedown', 'keydown', 'touchstart', 'touchmove', 'wheel', 'click'] as const
+    for (const e of events) document.addEventListener(e, armIdleTimer, { capture: true, passive: true })
+    armIdleTimer()
+
+    return () => {
+      if (idleTimer !== null) { clearTimeout(idleTimer); idleTimer = null }
+      for (const e of events) document.removeEventListener(e, armIdleTimer, { capture: true })
+    }
+  })
+
   function onSplashRetry() {
     import('$lib/state/boot.svelte').then(({ retryBoot }) => {
       retryBoot(appState.authMode ?? 'NONE', appState.authUser ?? '', appState.authPass ?? '')
@@ -187,6 +205,10 @@
   <SplashScreen mode="idle" showCards={settingsState.settings.splashCards ?? true} onDismiss={onIdleDismiss} />
 {/if}
 
+{#if appState.devSplash}
+  <SplashScreen mode="idle" showDevOverlay onDismiss={() => appState.devSplash = false} />
+{/if}
+
 {#if showApp}
   {#if strippedLayout}
     {@render children()}