diff --git a/README.md b/README.md
index e05e0fe..3919fa1 100644
--- a/README.md
+++ b/README.md
@@ -1435,14 +1435,16 @@ Things I chose while building, with the reasoning:
     navigations as the offline shell — a typo'd URL used to write the error page into the shell
     cache.
 
-87. **Chat's chrome docks into the rail (the sidebar seam).** The chat header and composer are
-    full-bleed bands inside the main pane; at desktop widths that pane starts right at the sidebar,
-    so both bands ended in a hard vertical edge beside the floating rail card — the 12px gutter
-    showed the raw scene, and the bands' fill + backdrop blur made it read as a color step at the
-    seam, with their hairlines starting in mid-air at that edge. Both bands now reach the card's
-    right edge (the rail's own 12px padding, expanded or collapsed) and their hairlines are inset
-    to the content box instead of touching the seam; phones keep the plain full-width borders. The
-    chat suite pins the dock (band edge === card edge, zeroed band borders, inset `::after`
+87. **Chat's chrome ends at the rail with a rounded corner (the sidebar seam).** The chat header
+    and composer are full-bleed bands inside the main pane; at desktop widths that pane starts right
+    at the sidebar, so both bands ended in a hard vertical edge beside the floating rail card — the
+    12px gutter showed the raw scene and the bands' fill + blur made it read as a color step at the
+    seam. Docking them into the card did not fix it either ("this seam still looks bad" — a straight
+    cut is still a straight cut): both bands now keep the rail's own 12px gutter and end in the
+    card's 1.5rem radius on their left side, so the ending is legible as deliberate, with their
+    hairlines inset instead of touching the seam (the header divider spans the flat part of the
+    bottom edge, from the corner curve inward). Phones keep the plain full-width borders. The chat
+    suite pins the geometry (12px gutter, 24px left corners, zeroed band borders, inset `::after`
     hairlines). The "Chat is set to ignore notes text" banner went away with it — the scope chip
     already says what the chat may read.
 
diff --git a/app/globals.css b/app/globals.css
index b6c3a47..472c023 100644
--- a/app/globals.css
+++ b/app/globals.css
@@ -691,7 +691,7 @@
 
 /* Chat header: the same glass as the cards, a touch more fill — its title and
    scope line sit directly over the sky. At lg its divider is the inset hairline
-   the desktop docking block below draws (::after), so it never hits the seam. */
+   the desktop block below draws (::after), so it never hits the seam. */
 .aero .chat-header {
   background-color: rgb(232 248 255 / 0.4);
   border-bottom: 1px solid rgb(255 255 255 / 0.6);
@@ -711,19 +711,19 @@
   background: rgb(255 255 255 / 0.65);
 }
 
-/* Desktop: the chat chrome docks into the rail. The header and the composer
-   are full-bleed bands inside the main pane; at lg that pane starts exactly
-   at the sidebar, so both bands used to stop in a hard vertical edge beside
-   the floating rail card — the scene showed through the 12px gutter and the
-   bands' own fill/blur made it read as a color step at the seam. They now
-   reach the card's right edge (the rail's own 12px padding, in the expanded
-   and the collapsed state alike) and their hairlines span the content box
-   instead of starting in mid-air at the seam. */
+/* Desktop: the chat chrome ends at the rail with a rounded corner. The header
+   and the composer are full-bleed bands inside the main pane, which starts
+   right at the sidebar; a straight vertical edge there read as a hard cut (the
+   12px gutter showed the raw scene and the bands' fill/blur made it a color
+   step at the seam). Both bands now stop at the seam with the rail card's own
+   1.5rem radius on their left end, so the ending reads as deliberate, and their
+   hairlines span the content box instead of touching the seam. Phones keep the
+   plain full-width borders. */
 @media (min-width: 1024px) {
   .chat-header {
-    margin-left: -0.75rem;
-    padding-left: 1.75rem;
     border-bottom: 0;
+    border-start-start-radius: 1.5rem;
+    border-end-start-radius: 1.5rem;
   }
   .aero .chat-header {
     border-bottom: 0;
@@ -731,17 +731,18 @@
   .chat-header::after {
     content: "";
     position: absolute;
-    left: 1.75rem;
+    left: 1.5rem;
     right: 1rem;
     bottom: 0;
     height: 1px;
     background: var(--glass-border);
   }
-  .chat-composer {
-    margin-left: -0.75rem;
+  .chat-composer,
+  .chat-composer-band {
+    border-start-start-radius: 1.5rem;
+    border-end-start-radius: 1.5rem;
   }
   .chat-composer-band {
-    padding-left: 3.25rem;
     border-top: 0;
   }
   .aero .chat-composer {
@@ -750,7 +751,7 @@
   .chat-composer::after {
     content: "";
     position: absolute;
-    left: 3.25rem;
+    left: 2.5rem;
     right: 2.5rem;
     top: 0;
     height: 1px;
diff --git a/package.json b/package.json
index a3a7213..8d9ec00 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "freezmo",
-  "version": "0.5.6",
+  "version": "0.5.7",
   "private": true,
   "license": "GPL-3.0-only",
   "scripts": {
diff --git a/public/sw.js b/public/sw.js
index 67ea82f..b2f3991 100644
--- a/public/sw.js
+++ b/public/sw.js
@@ -9,7 +9,7 @@
  *
  * Bumping CACHE_VERSION is how a new deploy invalidates old assets.
  */
-const CACHE_VERSION = "freezmo-v78";
+const CACHE_VERSION = "freezmo-v79";
 const SHELL_CACHE = `${CACHE_VERSION}-shell`;
 const ASSET_CACHE = `${CACHE_VERSION}-assets`;
 
diff --git a/tests/chat-test.mjs b/tests/chat-test.mjs
index 8e3591d..357ad42 100644
--- a/tests/chat-test.mjs
+++ b/tests/chat-test.mjs
@@ -291,12 +291,13 @@ try {
     await desktop.page.waitForTimeout(400);
     check("desktop: AI disclaimer under the composer", await desktop.page.getByText("Freezmo uses AI and can make mistakes").isVisible());
 
-    /* The chat chrome docks into the rail: the header and the composer used to
-       end in a hard vertical edge beside the floating rail card (the scene
-       showed through the gutter and their fill/blur made it read as a color
-       step at the seam), and their hairlines started right at that edge. Both
-       bands now reach the card's right edge and their hairlines are inset to
-       the content box. */
+    /* The chat chrome ends at the rail with the rail card's own radius: the
+       header and the composer are full-bleed bands inside the main pane, which
+       starts right at the sidebar — a straight vertical edge there read as a
+       hard cut (the 12px gutter showed the raw scene and the bands' fill/blur
+       made it a color step at the seam). Both now keep the rail's 12px gutter
+       and end in a 1.5rem rounded corner on their left side, with their
+       hairlines inset instead of touching the seam. */
     const seam = await desktop.page.evaluate(() => {
       const card = document.querySelector(".sidebar-surface");
       const header = document.querySelector(".chat-header");
@@ -304,23 +305,28 @@ try {
       if (!card || !header || !band) return null;
       const line = (el) => {
         const cs = getComputedStyle(el, "::after");
-        return { content: cs.content, left: parseFloat(cs.left), right: parseFloat(cs.right) };
+        return { content: cs.content, left: parseFloat(cs.left) };
       };
+      const hcs = getComputedStyle(header);
       return {
         cardRight: Math.round(card.getBoundingClientRect().right),
         headerLeft: Math.round(header.getBoundingClientRect().left),
         bandLeft: Math.round(band.getBoundingClientRect().left),
-        headerBorder: getComputedStyle(header).borderBottomWidth,
+        headerRadius: hcs.borderStartStartRadius,
+        headerEndRadius: hcs.borderEndStartRadius,
+        headerBorder: hcs.borderBottomWidth,
         bandBorder: getComputedStyle(band).borderTopWidth,
         headerLine: line(header),
         bandLine: line(band.parentElement),
       };
     });
     check(
-      "desktop: chat chrome docks into the rail (no seam)",
+      "desktop: chat chrome ends in a rounded corner at the seam",
       seam !== null &&
-        seam.headerLeft === seam.cardRight &&
-        seam.bandLeft === seam.cardRight &&
+        seam.headerLeft === seam.cardRight + 12 &&
+        seam.bandLeft === seam.cardRight + 12 &&
+        seam.headerRadius === "24px" &&
+        seam.headerEndRadius === "24px" &&
         seam.headerBorder === "0px" &&
         seam.bandBorder === "0px" &&
         seam.headerLine.content !== "none" &&