diff --git a/program/MainWindow.cs b/program/MainWindow.cs
index 83c5453..6d60b9f 100644
--- a/program/MainWindow.cs
+++ b/program/MainWindow.cs
@@ -662,16 +662,32 @@
 
     private bool ConfirmPowerOff()
     {
-        var dlg = new MessageDialog(this,
-            DialogFlags.Modal | DialogFlags.DestroyWithParent,
-            MessageType.Question, ButtonsType.None,
-            "{0}", _Language["Close.ConfirmPowerOff"]);
+         var dlg = new Dialog();
+        dlg.Name           = "PowerOffDialog";
+        dlg.TransientFor   = this;
+        dlg.Modal          = true;
+        dlg.Decorated      = false;                       // matchbox gives no useful frame
+        dlg.TypeHint       = Gdk.WindowTypeHint.Dialog;
+        dlg.WindowPosition = WindowPosition.CenterOnParent;
+        dlg.SetDefaultSize(780, 320);
 
-        dlg.AddButton(_Language["Common.Cancel"],   (int)ResponseType.Cancel);
-        dlg.AddButton(_Language["Common.PowerOff"], (int)ResponseType.Ok);
+        var msg = new Label(_Language["Close.ConfirmPowerOff"]);
+        msg.Name      = "PowerOffMessage";
+        msg.LineWrap  = true;
+        msg.Justify   = Justification.Center;
+
+        Box content = dlg.ContentArea;
+        content.Spacing = 0;
+        content.PackStart(msg, true, true, 0);
+
+        var cancel = (Button)dlg.AddButton(_Language["Common.Cancel"],   (int)ResponseType.Cancel);
+        var ok     = (Button)dlg.AddButton(_Language["Common.PowerOff"], (int)ResponseType.Ok);
+        cancel.Name = "PowerOffCancel";
+        ok.Name     = "PowerOffConfirm";
         dlg.DefaultResponse = ResponseType.Cancel;
 
-        var r = (ResponseType)dlg.Run();
+        dlg.ShowAll();
+        ResponseType r = (ResponseType)dlg.Run();
         dlg.Destroy();
         return r == ResponseType.Ok;
     }
diff --git a/program/info_eng.csv b/program/info_eng.csv
index c0094d3..2a4c5f0 100644
--- a/program/info_eng.csv
+++ b/program/info_eng.csv
@@ -29,4 +29,8 @@
 ConnectionAlertLabel,Problem connecting with device
 BatteryIcon.Charging,Battery {0}% — charging
 BatteryIcon.Discharging,Battery {0}%
-BatteryIcon.Full,Battery fully charged
\ No newline at end of file
+BatteryIcon.Full,Battery fully charged
+Close.ConfirmPowerOff,Shut down the tablet?
+Close.ShuttingDown,Shutting down...
+Common.Cancel,Cancel
+Common.PowerOff,Shut Down
\ No newline at end of file
diff --git a/program/info_jpn.csv b/program/info_jpn.csv
index c3c5735..41e131f 100644
--- a/program/info_jpn.csv
+++ b/program/info_jpn.csv
@@ -29,4 +29,8 @@
 ConnectionAlertLabel,デバイスに接続できません 
 BatteryIcon.Charging,バッテリー {0}% — 充電中
 BatteryIcon.Discharging,バッテリー {0}%
-BatteryIcon.Full,バッテリー 満充電
\ No newline at end of file
+BatteryIcon.Full,バッテリー 満充電
+Close.ConfirmPowerOff,タブレットの電源を切ります。よろしいですか？
+Close.ShuttingDown,シャットダウン中...
+Common.Cancel,キャンセル
+Common.PowerOff,電源を切る
\ No newline at end of file
diff --git a/program/touch_friendly.css b/program/touch_friendly.css
index 0c4851a..fbcd824 100644
--- a/program/touch_friendly.css
+++ b/program/touch_friendly.css
@@ -210,4 +210,44 @@
     margin: 8px 40px;
 }
 /* #BatteryLabel            { margin-left: 4px; } */
-#BatteryLabel.battery-low { color: #c62828; font-weight: bold; }
\ No newline at end of file
+#BatteryLabel.battery-low { color: #c62828; font-weight: bold; }
+
+/* ---------- power-off confirmation ---------- */
+/* Own toplevel, so the generic `window` and `button` rules at the top of
+   this file apply to it. Undo both, then restyle from scratch. */
+#PowerOffDialog {
+    background-image: none;
+    background-color: #FFFFFF;
+    border: 4px solid #0B3B6B;
+}
+#PowerOffDialog box,
+#PowerOffDialog .dialog-vbox,
+#PowerOffDialog .dialog-action-area {
+    background-color: transparent;
+    background-image: none;
+}
+
+#PowerOffMessage {
+    font-family: 'Noto Sans JP', 'IPAPGothic', 'Noto Sans', sans-serif;
+    font-size: 40px;
+    font-weight: 700;
+    color: #1e1e1e;
+    margin: 44px 40px 28px 40px;
+}
+
+#PowerOffDialog button {
+    min-height: 90px;
+    min-width: 280px;
+    margin: 0 20px 30px 20px;
+    border: 2px solid rgba(0,0,0,0.45);
+    border-radius: 0;
+}
+#PowerOffDialog button label { font-size: 34px; color: #ffffff; }
+
+#PowerOffCancel        { background-color: #808080; }
+#PowerOffCancel:hover  { background-color: #909090; }
+#PowerOffCancel:active { background-color: #6E6E6E; }
+
+#PowerOffConfirm        { background-color: #C62828; }
+#PowerOffConfirm:hover  { background-color: #D33A3A; }
+#PowerOffConfirm:active { background-color: #A61F1F; }
\ No newline at end of file