diff --git a/docs/DESIGN.md b/docs/DESIGN.md
index eae067e..6740057 100644
--- a/docs/DESIGN.md
+++ b/docs/DESIGN.md
@@ -496,7 +496,12 @@ text. On focus the border moves to faint. The field gets no glow, because a form
 - **Detail sheet:** `surface` fill with a hairline border and 16px corners. It rises from the bottom
   on a phone, is centred at `max-w-lg` from `sm` up, and sits over the scrim.
 - **Toast / update notice:** `raised` fill, hairline border, 12px corners and the only shadow in the
-  system. Each offers one action.
+  system. Each offers one action, and the "Moved to Archive" toast also a plain OK that only closes
+  it. That toast sits in the bottom-right corner, 24px in, at most 420px wide, so it stays off the
+  reading column and the events moving up into the gap; up to 700px wide there is no side to clear,
+  so it spans the width 16px in from each edge at the top, over the header, because at the bottom it
+  covered the end of an event's page opened while it was up. It was centred, for eight seconds,
+  until 2026-11-10, when the owner found it covering the next events.
 
 ### Daily burst
 A small spray of 3px sparks that fires once, in the row, when a reader finishes one thing: a daily
diff --git a/docs/PRD.md b/docs/PRD.md
index 122d565..0e1102d 100644
--- a/docs/PRD.md
+++ b/docs/PRD.md
@@ -193,7 +193,8 @@ the cut are still counted in the header, still on the timeline, and one tap away
 **F3 — Mark completed.**
 Done writes durable progress and a metadata snapshot immediately. A confirmation remains for about
 0.9 seconds (1.5 until 2026-10-20, which read as unresponsive) before the row fades/collapses into
-Archive. Undo is available for eight seconds; Archive Restore remains available afterwards. A failed
+Archive. Undo is offered in a toast, out of the list's way, for four seconds (eight until 2026-11-10, when it sat
+over the next events), and its OK closes it sooner; Archive Restore remains available afterwards. A failed
 write is disclosed and never presented as saved. Reduced motion removes the fade.
 
 **F4 — Settings and visibility.**
diff --git a/src/client/ReaderApp.tsx b/src/client/ReaderApp.tsx
index 038b654..e672ce6 100644
--- a/src/client/ReaderApp.tsx
+++ b/src/client/ReaderApp.tsx
@@ -69,6 +69,7 @@ import { ENTRIES, NOTES, newestId, unseen } from "../shared/changelog.ts";
 import {
   ARCHIVE_COLLAPSE_MS,
   ARCHIVE_HOLD_MS,
+  ARCHIVE_UNDO_MS,
   ChecklistEvent,
   leavingMarks,
   LedgerColumns,
@@ -498,7 +499,7 @@ function ReaderContent({
       () => setTransition((t) => (t ? { ...t, phase: "hidden" } : null)),
       ARCHIVE_COLLAPSE_MS,
     );
-    const undo = setTimeout(() => setTransition(null), 8000);
+    const undo = setTimeout(() => setTransition(null), ARCHIVE_UNDO_MS);
     return () => {
       clearTimeout(t);
       clearTimeout(collapse);
@@ -1137,21 +1138,29 @@ function ReaderContent({
                     transition.phase === "hold" && (
                       <Fireworks key={transition.key} />
                     )}
-                  {transition.label} “{transition.title}” · Moved to Archive{" "}
-                  <button
-                    type="button"
-                    onClick={() => {
-                      void dispatch({
-                        type: "restore",
-                        accountId: transition.accountId,
-                        eventId: transition.eventId,
-                        ...actionMeta(),
-                      });
-                      setTransition(null);
-                    }}
-                  >
-                    Undo
-                  </button>
+                  <span className="archive-toast-text">
+                    {transition.label} “{transition.title}” · Moved to Archive
+                  </span>
+                  <span className="archive-toast-actions">
+                    <button
+                      type="button"
+                      onClick={() => {
+                        void dispatch({
+                          type: "restore",
+                          accountId: transition.accountId,
+                          eventId: transition.eventId,
+                          ...actionMeta(),
+                        });
+                        setTransition(null);
+                      }}
+                    >
+                      Undo
+                    </button>
+                    {/* Closes the notice only: the event stays archived. */}
+                    <button type="button" onClick={() => setTransition(null)}>
+                      OK
+                    </button>
+                  </span>
                 </aside>
               )}
               {archivedOpen && (
diff --git a/src/client/components/redesign/ChecklistEvent.tsx b/src/client/components/redesign/ChecklistEvent.tsx
index ceecf65..207111c 100644
--- a/src/client/components/redesign/ChecklistEvent.tsx
+++ b/src/client/components/redesign/ChecklistEvent.tsx
@@ -56,7 +56,13 @@ export function UrgencyLegend() {
  * when it is gone once the 250 ms collapse has run.
  */
 export const ARCHIVE_HOLD_MS = 900,
-  ARCHIVE_COLLAPSE_MS = ARCHIVE_HOLD_MS + 250;
+  ARCHIVE_COLLAPSE_MS = ARCHIVE_HOLD_MS + 250,
+  /**
+   * How long the "Moved to Archive" toast offers Undo. Eight seconds until
+   * 2026-11-10, when the owner found it sitting over the next events; OK closes
+   * it sooner, and Archive Restore stays available after it is gone.
+   */
+  ARCHIVE_UNDO_MS = 4000;
 /**
  * The marks on a checklist row on its way to the Archive. While it holds, its
  * text greys; a completed one also gets the codes' shine, an ignored one does
diff --git a/src/client/redesign.css b/src/client/redesign.css
index b164c85..a70d07b 100644
--- a/src/client/redesign.css
+++ b/src/client/redesign.css
@@ -1003,25 +1003,53 @@ textarea {
   text-decoration: underline;
   text-underline-offset: 3px;
 }
+/* Bottom right, out of the reading column, so it does not sit over the next
+   events (centred until 2026-11-10). On a phone there is no side to move to,
+   and the bottom is where the list continues and an event's page ends, so it
+   spans the width at the top, over the header, instead. */
 .archive-toast {
   position: fixed;
   bottom: 24px;
-  left: 50%;
-  transform: translateX(-50%);
+  right: 24px;
   width: max-content;
-  max-width: calc(100vw - 32px);
+  max-width: min(420px, calc(100vw - 32px));
   z-index: 70;
-  padding: 14px 20px;
+  display: flex;
+  align-items: center;
+  gap: 6px 16px;
+  padding: 12px 16px;
+  border: 1px solid var(--color-hairline);
   border-radius: 12px;
   background: var(--color-raised);
   color: var(--color-ink);
   font-size: 13px;
   box-shadow: 0 8px 30px #0003;
 }
+.archive-toast-text {
+  min-width: 0;
+}
+.archive-toast-actions {
+  display: flex;
+  flex: none;
+  gap: 4px;
+}
 .archive-toast button {
+  min-height: 32px;
+  padding: 0 8px;
+  border-radius: 8px;
   color: var(--color-near);
-  margin-left: 14px;
   text-decoration: underline;
+  text-underline-offset: 3px;
+}
+@media (max-width: 700px) {
+  .archive-toast {
+    top: calc(16px + env(safe-area-inset-top, 0px));
+    bottom: auto;
+    left: 16px;
+    right: 16px;
+    width: auto;
+    max-width: none;
+  }
 }
 .archive-confirm {
   padding: 8px 20px;
diff --git a/test/redesign-checklist.test.tsx b/test/redesign-checklist.test.tsx
index 57df9f2..198e209 100644
--- a/test/redesign-checklist.test.tsx
+++ b/test/redesign-checklist.test.tsx
@@ -86,6 +86,7 @@ test("a completed event shines and greys while it holds, then fades; an ignored
 import {
   ARCHIVE_COLLAPSE_MS,
   ARCHIVE_HOLD_MS,
+  ARCHIVE_UNDO_MS,
 } from "../src/client/components/redesign/ChecklistEvent.tsx";
 test("a completed event holds under a second, long enough for its shine, then collapses", () => {
   expect(ARCHIVE_HOLD_MS).toBe(900);
@@ -94,3 +95,8 @@ test("a completed event holds under a second, long enough for its shine, then co
   // The collapse waits out the 250 ms max-height transition.
   expect(ARCHIVE_COLLAPSE_MS - ARCHIVE_HOLD_MS).toBe(250);
 });
+test("the Moved to Archive notice offers Undo for four seconds, outlasting the row's collapse", () => {
+  // Halved from eight on 2026-11-10: the notice sat over the next events.
+  expect(ARCHIVE_UNDO_MS).toBe(4000);
+  expect(ARCHIVE_UNDO_MS).toBeGreaterThan(ARCHIVE_COLLAPSE_MS);
+});