diff --git a/components/answered-card.tsx b/components/answered-card.tsx
index 70cb9f2..30c509a 100644
--- a/components/answered-card.tsx
+++ b/components/answered-card.tsx
@@ -41,9 +41,16 @@ export function AnsweredCard({ answer }: { answer: QuestionAnswerData }) {
 		    ThinkingBlock, instead of an inset inside the answer. Same muted
 		    rail as before; the label is now plain "Your thinking". */}
 		{answer.readingThinking && (
-			<ThinkingBlock testId="reading-thinking-block" label="YOUR THINKING" text={answer.readingThinking} />
+			<ThinkingBlock testId="reading-thinking-block" label="YOUR THINKING" text={answer.readingThinking} defaultOpen />
 		)}
-		<div className="rounded-xl border bg-card p-4 text-card-foreground" data-testid="answered-card">
+		{/* [&>*:last-child]:mb-0 (owner round, 2026-10-07): on ask cards the
+		    thinking row is the last child — its my-3 stacked with the card's
+		    p-4 into a 28px void below (12px above); the card's own padding is
+		    the bottom rhythm when a row ends the card. */}
+		<div
+			className="rounded-xl border bg-card p-4 text-card-foreground [&>*:last-child]:mb-0"
+			data-testid="answered-card"
+		>
 			<div className="mb-1 flex items-center gap-2 text-xs font-medium uppercase tracking-wide text-muted-foreground">
 				{isQuiz ? (answer.questionType === "predict" ? "Prediction" : "Quiz") : isExplain ? "Explain" : "Question"}
 				{isQuiz &&
@@ -137,9 +144,15 @@ export function AnsweredCard({ answer }: { answer: QuestionAnswerData }) {
 			{(answer.thinking ?? answer.note) && (
 				/* The SAME unified row (owner round, 2026-10-05): the quiz answer's
 				    thinking is the identical collapsible ThinkingBlock — it just
-				    happens to sit inside the quiz container. Same placement, same
-				    trigger, same 50%-italic quote block on expand. */
-				<ThinkingBlock testId="your-thinking" label="YOUR THINKING" text={answer.thinking ?? answer.note ?? ""} />
+				    happens to sit INSIDE the card, so it takes the rail but no band
+				    (owner round two, 2026-10-07: card-color on card-color would be
+				    invisible; geometry alone carries it there). */
+				<ThinkingBlock
+					testId="your-thinking"
+					label="YOUR THINKING"
+					text={answer.thinking ?? answer.note ?? ""}
+					banded={false}
+				/>
 			)}
 
 			{/* px-3→removed: card p-4 + box px-3 double-inset sat the "Why" label deeper
diff --git a/components/chat.tsx b/components/chat.tsx
index fe8ad09..7b6e9b4 100644
--- a/components/chat.tsx
+++ b/components/chat.tsx
@@ -1399,12 +1399,13 @@ export function Chat({
 										    Rendered WITHOUT the Message wrapper — that is the bubble. */
 											<div
 										data-testid="user-message"
-										/* SIDE-BASED AUTHORSHIP (owner round, 2026-10-07): the
-										    document shape blurred user into agent — three left-rail
-										    idioms (user text, user thinking, quoted prose) collided.
-										    User rows go RIGHT: mirrored rail, ~85% width, text still
-										    reading left-to-right (the chat convention). */
-										className="my-1 ml-auto w-[85%] border-r-2 border-muted-foreground/30 pr-[calc(3ch-2px)] font-ui text-xs"
+										/* THE DOCUMENT, ALL-IN (owner round two, 2026-10-07): no
+										    chat side — the user message is a full-width card-color
+										    BAND with the 6px rail, the same geometry as the thinking
+										    rows (the band is the authorship mark against the agent's
+										    transparent prose). The "You" label stays — one register
+										    with the thinking labels. */
+										className="my-2 w-full border-l-[6px] border-muted-foreground/30 bg-card py-2.5 pl-[calc(3ch-6px)] pr-2 font-ui text-xs"
 									>
 												{/* The rail GROUPS (owner round 4, 2026-10-05): the YOU heading
 												    sits INSIDE the rail, same mono-xs register and same 1ch
diff --git a/components/practice-cards.tsx b/components/practice-cards.tsx
index cb93aa2..392f8a7 100644
--- a/components/practice-cards.tsx
+++ b/components/practice-cards.tsx
@@ -293,8 +293,6 @@ export function ThinkingCard({ data }: { data: PracticeThinkingData }) {
 	// The unified row (owner rounds, 2026-10-05): one style, one label —
 	// 50%-italic quote block on expand. Legacy records' commit flag is
 	// deliberately unread (one lane now). A TRANSCRIPT row (owner round,
-	// 2026-10-07): mirrored to the right side, arriving expanded.
-	return (
-		<ThinkingBlock testId="thinking-card" label="YOUR THINKING" text={data.text} mirror defaultOpen />
-	);
+	// 2026-10-07): full-width band + rail, arriving expanded.
+	return <ThinkingBlock testId="thinking-card" label="YOUR THINKING" text={data.text} defaultOpen />;
 }
diff --git a/components/thinking-block.tsx b/components/thinking-block.tsx
index d026972..9af771d 100644
--- a/components/thinking-block.tsx
+++ b/components/thinking-block.tsx
@@ -17,12 +17,17 @@ import { cn } from "@/lib/utils";
  *  The glance-level law (owner): user thinking = rail + 50% italic;
  *  agent thinking = no rail.
  *
- *  SIDE-BASED AUTHORSHIP (owner round, 2026-10-07): transcript-level rows
- *  go RIGHT — mirrored rail (border-right), block hugging the right edge
- *  at ~85% width, text still reading left-to-right. In-card rows (inside
- *  the answered card, the agent's context) stay left. `mirror` selects
- *  the side; `defaultOpen` marks the transcript rows, which arrive
- *  EXPANDED (owner: clearly conveyed that the thinking was sent).
+ *  THE DOCUMENT, ALL-IN (owner round two, 2026-10-07): no chat sides —
+ *  transcript-level user rows (this block, the "You" message) are
+ *  full-width CARD-COLOR BANDS: the band is the authorship mark against
+ *  the agent's transparent prose, and the rail runs along the band's left
+ *  edge. The rail keeps its muted color but is now 6px wide, eating the
+ *  artificial air of the old 3ch inset — the total inset STAYS 3ch so the
+ *  chevron-alignment law with the agent's flush rows survives; the gap
+ *  between rail and text drops to natural (3ch - 6px). In-card rows
+ *  (inside the answered card, on the card's own background) take the rail
+ *  but NO band (`banded: false`). `defaultOpen` marks transcript rows,
+ *  which arrive EXPANDED (clearly conveyed that the thinking was sent).
  *
  *  ⌘T (toggle-user-thinking) sets EVERY row to one state via the module
  *  store below — one source of truth, no provider tree: rows subscribe on
@@ -61,7 +66,7 @@ export function ThinkingBlock({
 	text,
 	testId,
 	dataCommit,
-	mirror = false,
+	banded = true,
 	defaultOpen = false,
 }: {
 	label?: string;
@@ -69,8 +74,8 @@ export function ThinkingBlock({
 	testId?: string;
 	/** The practice marker's register flag (commit vs nudge). */
 	dataCommit?: boolean;
-	/** Right-side placement (transcript rows): mirrored rail, right edge. */
-	mirror?: boolean;
+	/** Transcript rows carry the card-color band; in-card rows rail only. */
+	banded?: boolean;
 	/** Transcript rows arrive expanded (owner, 2026-10-07). */
 	defaultOpen?: boolean;
 }) {
@@ -95,15 +100,14 @@ export function ThinkingBlock({
 		<div
 			data-testid={testId}
 			data-commit={dataCommit === undefined ? undefined : dataCommit ? "true" : "false"}
-			data-side={mirror ? "right" : "left"}
 			className={cn(
-				// my-3 (owner, 2026-10-07): the row's own rhythm — 4px hugged the
-				// options on non-graded answered cards; 12px matches the card's
-				// mt-2/mt-3 spacing grammar.
-				"lh-card-enter my-3 font-ui text-xs",
-				mirror
-					? "ml-auto w-[85%] border-r-2 border-muted-foreground/30 pr-[calc(3ch-2px)]"
-					: "w-full border-l-2 border-muted-foreground/30 pl-[calc(3ch-2px)]",
+				// The rail geometry (owner round two, 2026-10-07): total inset
+				// STAYS 3ch (the chevron-alignment law with the agent's flush
+				// rows), re-split — 6px rail (was 2px) + a natural 3ch-6px gap
+				// (was the too-wide 3ch-2px). In-card rows keep the 12px my-3
+				// rhythm; banded rows sit my-2 apart (the band's own air).
+				"lh-card-enter w-full border-l-[6px] border-muted-foreground/30 pl-[calc(3ch-6px)] font-ui text-xs",
+				banded ? "my-2 bg-card py-2.5" : "my-3",
 			)}
 		>
 			<button
@@ -111,7 +115,7 @@ export function ThinkingBlock({
 				data-testid={testId ? `${testId}-trigger` : undefined}
 				onClick={() => setOpen((v) => !v)}
 				aria-expanded={open}
-				className="flex w-full items-center gap-2 font-medium uppercase tracking-wide text-muted-foreground transition-colors hover:text-foreground"
+				className="flex w-full items-center gap-2 pr-2 font-medium uppercase tracking-wide text-muted-foreground transition-colors hover:text-foreground"
 			>
 				{label}
 				<ChevronDownIcon className={cn("size-4 shrink-0 transition-transform", open ? "rotate-180" : "rotate-0")} />
diff --git a/tests/render-cards.test.tsx b/tests/render-cards.test.tsx
index 46a3073..4bda35f 100644
--- a/tests/render-cards.test.tsx
+++ b/tests/render-cards.test.tsx
@@ -295,9 +295,13 @@ describe("render smoke tests", () => {
 		// trigger row only — the thinking text is one click away, never loud.
 		assert.ok(html.includes('data-testid="your-thinking-trigger"'), "the trigger row");
 		assert.ok(html.includes('aria-expanded="false"'), "arrives collapsed");
+		// IN-CARD = RAIL ONLY (owner round two, 2026-10-07): no band on the
+		// card's own background; geometry alone carries it there.
+		const yourRow = html.slice(html.indexOf('data-testid="your-thinking"'));
+		assert.ok(!yourRow.slice(0, 400).includes("bg-card"), "no band inside the card");
 		// THE RAIL GROUPS (owner correction): the label sits INSIDE the rail —
 		// ownership readable from the rail alone, collapsed or expanded.
-		const railAt = html.indexOf("border-l-2");
+		const railAt = html.indexOf("border-l-[6px]");
 		const trigAt = html.indexOf("your-thinking-trigger");
 		assert.ok(railAt !== -1 && railAt < trigAt, "the rail opens before the label (same quote)");
 		assert.ok(!html.includes("brightness isn&#x27;t distance"), "the text is hidden until expanded");
@@ -591,9 +595,9 @@ describe("predict vs check rendering", () => {
 			readingThinking: "was unsure mid-paragraph",
 		});
 		const html = renderToStaticMarkup(<AnsweredCard answer={withReading} />);
-		// The unified ThinkingBlock (owner round, 2026-10-05): the reading
-		// thoughts render BEFORE the card as the collapsed user-thinking row
-		// — same trigger, same 50%-italic quote block on expand.
+		// The unified ThinkingBlock (owner round, 2026-10-05; round two
+		// 2026-10-07): the reading thoughts render BEFORE the card as the
+		// banded user-thinking row, arriving EXPANDED (clearly sent).
 		const blockAt = html.indexOf("reading-thinking-block");
 		const cardAt = html.indexOf("answered-card");
 		assert.ok(blockAt !== -1, "the lifted block renders");
@@ -601,9 +605,11 @@ describe("predict vs check rendering", () => {
 		assert.ok(html.includes("YOUR THINKING"), "the plain label");
 		assert.ok(!html.includes("Your thinking while reading"), "the old verbose label is gone");
 		assert.ok(!html.includes("your-reading-thinking"), "the in-card inset is gone");
-		// COLLAPSED ARRIVAL: SSR shows the triggers, not the texts.
+		// EXPANDED ARRIVAL (owner round two, 2026-10-07): transcript rows
+		// render their text; the in-card answer thinking stays collapsed.
 		assert.ok(html.includes('data-testid="your-thinking-trigger"'), "the answer thinking stays inside the card");
-		assert.ok(!html.includes("answering thought") && !html.includes("was unsure mid-paragraph"), "texts hidden until expanded");
+		assert.ok(html.includes("was unsure mid-paragraph"), "the lifted row arrives expanded");
+		assert.ok(!html.includes("answering thought"), "the in-card row stays collapsed");
 		const legacy = { ...buildAnswer(quizQD(), { values: ["Mercury"] }), note: "a 2026-09 answer" };
 		const legacyHtml = renderToStaticMarkup(<AnsweredCard answer={legacy} />);
 		assert.ok(legacyHtml.includes("a 2026-09 answer") || legacyHtml.includes('data-testid="your-thinking-trigger"'), "records from before the rename still render");
diff --git a/tests/render-md-blocks.test.tsx b/tests/render-md-blocks.test.tsx
index fb03e15..a67df08 100644
--- a/tests/render-md-blocks.test.tsx
+++ b/tests/render-md-blocks.test.tsx
@@ -243,19 +243,21 @@ describe("md-blocks — the restored plain blockquote (owner round, 2026-10-07)"
 });
 
 describe("ThinkingBlock — side-based authorship + ⌘T sync (owner round, 2026-10-07)", () => {
-	it("the default row stays left with the my-3 rhythm", () => {
-		const html = renderToStaticMarkup(<ThinkingBlock text="left side" />);
-		assert.ok(html.includes("border-l-2"), "left rail");
-		assert.ok(html.includes("my-3"), "the 12px rhythm (was my-1)");
+	it("the banded row is the document band — full-width card color, 6px rail", () => {
+		const html = renderToStaticMarkup(<ThinkingBlock text="banded" defaultOpen />);
+		assert.ok(html.includes("bg-card"), "the card-color band");
+		assert.ok(html.includes("border-l-[6px]"), "the 6px rail");
+		assert.ok(html.includes("pl-[calc(3ch-6px)]"), "natural gap, 3ch total inset preserved");
+		assert.ok(html.includes("w-full"), "full width — no chat side");
+		assert.match(html, /aria-expanded="true"/);
+		assert.ok(html.includes("banded"), "text visible on arrival");
 	});
 
-	it("mirrored rows hug the right edge, rail flipped, arriving open", () => {
-		const html = renderToStaticMarkup(<ThinkingBlock text="right side" mirror defaultOpen />);
-		assert.ok(html.includes('data-side="right"'));
-		assert.ok(html.includes("ml-auto"), "pushed to the right edge");
-		assert.ok(html.includes("border-r-2") && !html.includes("border-l-2"), "rail on the right");
-		assert.match(html, /aria-expanded="true"/);
-		assert.ok(html.includes("right side"), "text visible on arrival");
+	it("in-card rows take the rail but no band", () => {
+		const html = renderToStaticMarkup(<ThinkingBlock text="in card" banded={false} />);
+		assert.ok(!html.includes("bg-card"), "no band on the card's own background");
+		assert.ok(html.includes("border-l-[6px]"), "the rail stays");
+		assert.ok(html.includes("my-3"), "the 12px in-card rhythm");
 	});
 
 	it("⌘T sets every row — explicit sets stomp individual state, late mounts honor the last set", () => {
diff --git a/tests/render-practice-surface.test.tsx b/tests/render-practice-surface.test.tsx
index 5b14b1d..e4d16d0 100644
--- a/tests/render-practice-surface.test.tsx
+++ b/tests/render-practice-surface.test.tsx
@@ -179,12 +179,13 @@ describe("the practice transcript cards", () => {
 	it("ThinkingCard: one label, right side, expanded arrival (owner round, 2026-10-07)", () => {
 		const trace = renderToStaticMarkup(<ThinkingCard data={{ problemCallId: "c", commit: false, text: "stuck at step two" }} />);
 		assert.match(trace, /YOUR THINKING/);
-		// Transcript rows arrive EXPANDED (clearly conveyed as sent) and
-		// MIRRORED right (side-based authorship).
+		// Transcript rows arrive EXPANDED (clearly conveyed as sent) as
+		// full-width card-color bands with the 6px rail (the document,
+		// all-in — owner round two, 2026-10-07).
 		assert.match(trace, /aria-expanded="true"/);
 		assert.ok(trace.includes("stuck at step two"), "the text is visible on arrival");
-		assert.ok(trace.includes('data-side="right"'), "mirrored to the right side");
-		assert.ok(trace.includes("border-r-2"), "the rail is on the right");
+		assert.ok(trace.includes("bg-card"), "the card-color band");
+		assert.ok(trace.includes("border-l-[6px]"), "the 6px rail, left side");
 		const legacy = renderToStaticMarkup(<ThinkingCard data={{ problemCallId: "c", commit: true, text: "It is 42." }} />);
 		assert.match(legacy, /YOUR THINKING/);
 		assert.doesNotMatch(legacy, /Your solution/);