diff --git a/A00_Common/b_page_state.ts b/A00_Common/b_page_state.ts
index 2c411ffe8..37d5c757f 100644
--- a/A00_Common/b_page_state.ts
+++ b/A00_Common/b_page_state.ts
@@ -64,6 +64,8 @@ export const STATE_REGISTRY = {
   "m02-combo-panel-width": { bucket: "pref", scope: "global" },
   /** M02 면적산출 카드 미리보기 아래 알약 줄 보임(기본 숨김 · 상세는 늘 보임) */
   "m02-card-pills": { bucket: "pref", scope: "global" },
+  /** M01 단가산출 로직 상세 오른쪽 — 열린 패널 하나(flow · source · none) */
+  "m01-logic-panel": { bucket: "pref", scope: "global" },
   /** B05 계획노선 편집 창 — 보던 화면(회전 · 가운데 · 배율). 프로젝트마다 따로 */
   "routeedit-view": { bucket: "pref", scope: "project" },
   /** B05 계획노선 편집 창 — 시점 · 종점 · 교각점 고정. [저장] 대상이 아니라 draft 에 안 둠 */
diff --git a/M01_MasterData/M01_MasterData_Router.py b/M01_MasterData/M01_MasterData_Router.py
index f487a6d78..5b0aaa349 100644
--- a/M01_MasterData/M01_MasterData_Router.py
+++ b/M01_MasterData/M01_MasterData_Router.py
@@ -190,6 +190,12 @@ def get_logic(key: str) -> dict:
     return _call(store.logic, key)
 
 
+@router.get("/logic/source")
+def get_logic_source(src: str) -> dict:
+    """로직 원문 — 출처 글로 찾은 품셈 본문 절(읽기만)."""
+    return _call(make.source, src)
+
+
 @router.get("/logic/auto")
 def get_logic_auto(key: str) -> dict:
     """견본 입력 — 마스터 보기용 자동값(프로젝트 기본값 아님) · 흐름 로직은 설계 예시값."""
diff --git a/M01_MasterData/M01_MasterData_Store_Make.py b/M01_MasterData/M01_MasterData_Store_Make.py
index 76dc319d9..c5ab2df45 100644
--- a/M01_MasterData/M01_MasterData_Store_Make.py
+++ b/M01_MasterData/M01_MasterData_Store_Make.py
@@ -103,6 +103,79 @@ def sections(book: str, division: str = "", chapter: str = "", q: str = "", limi
     return {"total": len(hits), "sections": hits[: min(max(limit, 1), 1000)]}
 
 
+# ── 로직 원문(출처 글 → 품셈 본문 절) ──────────────────────────────────
+_NUMBER = re.compile(r"(?<![\d-])\d+(?:-\d+)+(?![\d-])")
+
+
+def _blocks(lines: list[str]) -> list[dict]:
+    """md 줄 → 화면 조각 — 제목 {h} · 표 {table} · 글 {p} · 주석 줄은 뺌."""
+    out: list[dict] = []
+    for line in lines:
+        text = line.strip()
+        if not text or text.startswith("<!--"):
+            continue
+        if text.startswith("#"):
+            out.append({"h": len(text) - len(text.lstrip("#")), "text": text.lstrip("#").strip()})
+        elif text.startswith("|"):
+            cells = [c.strip() for c in text.strip("|").split("|")]
+            if all(re.fullmatch(r":?-{3,}:?", c) for c in cells):
+                continue  # 머리 · 몸 가름 줄
+            if not out or "table" not in out[-1]:
+                out.append({"table": []})
+            out[-1]["table"].append(cells)
+        else:
+            out.append({"p": text})
+    return out
+
+
+def _section(book: str, division: str, number: str) -> dict | None:
+    """번호 절을 품셈 본문에서 찾음 — 없으면 끝 마디를 하나씩 떼며 위 절로(두 마디까지)."""
+    parts = number.split("-")
+    folders = [f for d, no, _t, f in _chapters(book) if d == division and int(no) == int(parts[0])]
+    for upto in range(len(parts), 1, -1):
+        want = "-".join(parts[:upto])
+        for folder in folders:
+            for md in sorted(folder.glob("*.md")):
+                lines = md.read_text(encoding="utf-8").split("\n")
+                for i, line in enumerate(lines):
+                    m = _HEAD.match(line)
+                    if not m or m.group(1) != want:
+                        continue
+                    level = len(line) - len(line.lstrip("#"))
+                    end = next(
+                        (
+                            j
+                            for j in range(i + 1, len(lines))
+                            if _HEAD.match(lines[j])
+                            and len(lines[j]) - len(lines[j].lstrip("#")) <= level
+                        ),
+                        len(lines),
+                    )
+                    return {
+                        "number": number,
+                        "matched": want,
+                        "file": md.relative_to(BODY.parent).as_posix(),
+                        "blocks": _blocks(lines[i:end]),
+                    }
+    return None
+
+
+def source(src: str) -> dict:
+    """로직 출처 글(예 「건설품셈 토목 1-1-2」 · 「산림품셈 3-4-2 1」)로 찾은 품셈 원문 절 —
+    번호가 여럿이면(「8-1-5 · 8-1-6」) 절마다 · 못 찾으면 found 빈 목록(화면 「원문 연결 없음」)."""
+    words = src.split()
+    book = words[0] if words else ""
+    if book not in BOOKS:
+        return {"source": src, "found": []}
+    division = (
+        next((d for d in cm.DIVISIONS if src.startswith(f"{book} {d} ")), "")
+        if book == "건설품셈"
+        else ""
+    )
+    found = [_section(book, division, n) for n in dict.fromkeys(_NUMBER.findall(src))]
+    return {"source": src, "found": [x for x in found if x]}
+
+
 # ── 표 조건 값 ─────────────────────────────────────────────────────────
 def table_options(file: str, key: str) -> dict:
     """표 조건 칸의 값만 — 표 몸을 통째로 받지 않으려는 자리(만들기 입력 제안)."""
diff --git a/M01_MasterData/M01_MasterData_UI_LogicLab.ts b/M01_MasterData/M01_MasterData_UI_LogicLab.ts
index 9e4ff7788..5c78792b7 100644
--- a/M01_MasterData/M01_MasterData_UI_LogicLab.ts
+++ b/M01_MasterData/M01_MasterData_UI_LogicLab.ts
@@ -52,6 +52,7 @@ import {
   type LogicFlow,
 } from "./M01_MasterData_UI_LogicLab_Flow";
 import { askBasicInfo } from "./M01_MasterData_UI_LogicLab_Basic";
+import { buildLogicSide } from "./M01_MasterData_UI_LogicLab_Side";
 import { buildHeadBar } from "./M01_MasterData_UI_Head";
 import { fetchSessionUser } from "../A06_Login/A06_Login_Api_Fetch";
 import type { CfLogic } from "../M02_MasterTemplete/DataFlow/M02_DF_Model";
@@ -129,6 +130,8 @@ export async function mountM01LogicLab(
   const editor = el("div", { className: "m01-logic__editor" });
   // 로직 상세 두 칸 — 왼쪽 지금 내용 · 오른쪽 흐름도(패널 자리) · 너비 비율 기억
   const split = buildSplit(editor);
+  // 오른쪽 두 패널(흐름도 · 원문) — 하나만 열림 · 흐름도는 이 칸 안에 띄움
+  const panes = buildLogicSide(split);
   const errors = el("div", { className: "m01-logic__reasons", attrs: { hidden: "" } });
   const calc = el("div", { className: "m01lab__calc" });
   const filterHost = el("div");
@@ -273,7 +276,9 @@ export async function mountM01LogicLab(
   const startFlow = async (o: Opened): Promise<void> => {
     const row = o.row;
     if (!row) return;
-    split.right.replaceChildren(el("p", { className: "m01lab-flow__wait", text: tf("Waiting") }));
+    panes.flowSplit.right.replaceChildren(
+      el("p", { className: "m01lab-flow__wait", text: tf("Waiting") }),
+    );
     const own = flowOf(row);
     const got = own || o.origKey === null ? null : await fetchFlow(o.origKey, o.file);
     // 시험 입력 한 벌 — 열 때 왼쪽 시험 계산 입력을 흐름 변수 예시값으로
@@ -284,7 +289,9 @@ export async function mountM01LogicLab(
     if (opened !== o) return;
     try {
       const made = await mountLogicFlow({
-        split,
+        split: panes.flowSplit,
+        folded: panes.flowFolded(),
+        onFold: (on) => panes.pick(on ? "none" : "flow"),
         flow: clone(o.flowBase),
         title: row.이름 || row.키,
         readOnly: !admin,
@@ -307,9 +314,10 @@ export async function mountM01LogicLab(
       });
       if (opened !== o) return made.destroy();
       flowNow = made;
+      panes.bindFlow(made.fold);
       made.setExamples(o.values); // 띄우는 사이에 온 자동값까지
     } catch (e) {
-      split.right.replaceChildren(
+      panes.flowSplit.right.replaceChildren(
         el("p", { className: "m01-logic__muted", text: tf("Failed", String(e)) }),
       );
     }
@@ -344,7 +352,9 @@ export async function mountM01LogicLab(
   const show = (next: Opened | null): void => {
     flowNow?.destroy();
     flowNow = null;
+    panes.bindFlow(null);
     opened = next;
+    panes.showSource(next?.row?.출처 ?? "");
     errors.hidden = true;
     drawEditor();
     drawCalc();
diff --git a/M01_MasterData/M01_MasterData_UI_LogicLab_Detail.ts b/M01_MasterData/M01_MasterData_UI_LogicLab_Detail.ts
index a6dd8aa49..8cbac7323 100644
--- a/M01_MasterData/M01_MasterData_UI_LogicLab_Detail.ts
+++ b/M01_MasterData/M01_MasterData_UI_LogicLab_Detail.ts
@@ -1,8 +1,8 @@
 /* =============================================================================
  * M01_MasterData_UI_LogicLab_Detail.ts
  * 「단가산출 로직」 상세 화면 — 컨테이너 넷을 위에서 아래로
- *   ① 기본정보(정본은 읽기 전용 · 비고만 고침) ② 단가산출 상세(인력·자재·경비·그 밖 묶음 + 소계)
- *   ③ 텍스트 수식(자리 — `_LogicLab_Formula.ts`) ④ 시험 계산(입력값 + 결과값 — `Logic_Calc` 그대로)
+ *   ① 기본정보(정본은 읽기 전용 · 비고만 고침) ② 시험 계산(입력값 + 결과값 — `Logic_Calc` 그대로)
+ *   ③ 단가산출 상세(인력·자재·경비·그 밖 묶음 + 소계) ④ 텍스트 수식(자리 — `_LogicLab_Formula.ts`)
  * 호표 줄을 누르면 그 줄이 쓰는 자료 모달(`_LogicLab_Modal.ts`)
  * ========================================================================== */
 
@@ -70,7 +70,7 @@ export interface DetailContext {
   /** 자체 로직 편집기 자리 — 다시 그려도 같은 칸을 씀(고치던 값이 안 날아감) */
   ownHost: HTMLElement;
   onChange: () => void;
-  /** 시험 계산 칸(`buildCalc` 가 채움) — 넷째 컨테이너 안에 놓음 */
+  /** 시험 계산 칸(`buildCalc` 가 채움) — 둘째 컨테이너 안에 놓음 */
   calcHost: HTMLElement;
   /** 흐름이 있는 로직 — 이 칸에 왼쪽 「지금 내용」(단가산출 상세 · 텍스트 수식 = `buildFlowView`)을 그림 ·
    * 있으면 호표 · 읽는 식 두 묶음 대신 이 칸을 놓음(기본정보 · 시험 계산은 그대로) */
@@ -487,8 +487,8 @@ export function buildLabDetail(host: HTMLElement, ctx: DetailContext): void {
       : null;
   host.replaceChildren(
     infoBox(ctx),
-    ...(ctx.flowHost ? [ctx.flowHost] : [hoBox(ctx), section(tl("Formula_Title"), [formula])]),
     section(tl("Calc_Title"), [ctx.calcHost]),
+    ...(ctx.flowHost ? [ctx.flowHost] : [hoBox(ctx), section(tl("Formula_Title"), [formula])]),
   );
   const own = kept?.node.dataset.own; // 기본정보 칸은 새로 만들어지므로 이름표로 다시 찾음
   const back = own ? host.querySelector<HTMLInputElement>(`[data-own="${own}"]`) : kept?.node;
diff --git a/M01_MasterData/M01_MasterData_UI_LogicLab_Flow.ts b/M01_MasterData/M01_MasterData_UI_LogicLab_Flow.ts
index e673caed8..c8bb785aa 100644
--- a/M01_MasterData/M01_MasterData_UI_LogicLab_Flow.ts
+++ b/M01_MasterData/M01_MasterData_UI_LogicLab_Flow.ts
@@ -235,6 +235,9 @@ export interface LogicFlowOpts {
   /** 흐름 로직이면 왼쪽 「지금 내용」 자리(LogicLab_Detail 의 flowHost) */
   leftHost(): HTMLElement | null;
   onChange(lg: CfLogic): void;
+  /** 패널 접힘 — 부르는 쪽(오른쪽 두 패널)이 정함 */
+  folded?: boolean;
+  onFold?(on: boolean): void;
 }
 
 export interface LogicFlow {
@@ -244,6 +247,8 @@ export interface LogicFlow {
   redrawLeft(): void;
   /** 왼쪽 시험 계산 입력이 바뀜 — 같은 이름 변수의 예시값으로(고친 것 아님) */
   setExamples(vals: Record<string, string>): void;
+  /** 패널 접기 · 펴기 */
+  fold(on: boolean): void;
   destroy(): void;
 }
 
@@ -312,6 +317,8 @@ export async function mountLogicFlow(opts: LogicFlowOpts): Promise<LogicFlow> {
     readOnly: opts.readOnly,
     logics: getLogic,
     onResize: (px) => opts.split.setRight(px),
+    folded: opts.folded,
+    onFold: opts.onFold,
     onChange: (next) => {
       lg = next;
       opts.onChange(next);
@@ -329,6 +336,7 @@ export async function mountLogicFlow(opts: LogicFlowOpts): Promise<LogicFlow> {
       refresh();
     },
     redrawLeft: left,
+    fold: (on) => panel.fold(on),
     setExamples: (vals) => {
       const next = withExamples(lg, vals);
       if (JSON.stringify(next) === JSON.stringify(lg)) return;
diff --git a/M01_MasterData/M01_MasterData_UI_LogicLab_Side.css b/M01_MasterData/M01_MasterData_UI_LogicLab_Side.css
new file mode 100644
index 000000000..711326450
--- /dev/null
+++ b/M01_MasterData/M01_MasterData_UI_LogicLab_Side.css
@@ -0,0 +1,54 @@
+/* 로직 상세 오른쪽 두 패널 — 흐름도 · 원문 · 접힌 패널은 얇은 띠 */
+.m01lab-side {
+  display: flex;
+  align-items: stretch;
+  min-width: 0;
+}
+
+.m01lab-side__slot {
+  flex: 0 0 40px;
+  min-width: 0;
+}
+
+.m01lab-side__slot.is-open {
+  flex: 1 1 auto;
+}
+
+/* 접힌 흐름도 자리 — 띠만(기다림 글 · 변환 알림은 숨김) */
+.m01lab-side__slot:not(.is-open) > :not(.m01lab-flow__panel, .m01lab-src) {
+  display: none;
+}
+
+.m01lab-src__body {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-8);
+  min-width: 0;
+  max-height: 80vh;
+  overflow: auto;
+}
+
+.m01lab-src__head {
+  margin: var(--spacing-8) 0 0;
+}
+
+.m01lab-src__p {
+  margin: 0;
+  white-space: pre-wrap;
+  line-height: 1.6;
+}
+
+.m01lab-src__file {
+  margin: 0;
+  font-size: var(--text-body-sm);
+  word-break: break-all;
+}
+
+.m01lab-src__none {
+  margin: 0;
+  font-weight: 600;
+}
+
+.m01lab-src__table td {
+  white-space: nowrap;
+}
diff --git a/M01_MasterData/M01_MasterData_UI_LogicLab_Side.ts b/M01_MasterData/M01_MasterData_UI_LogicLab_Side.ts
new file mode 100644
index 000000000..13f8da260
--- /dev/null
+++ b/M01_MasterData/M01_MasterData_UI_LogicLab_Side.ts
@@ -0,0 +1,191 @@
+/* =============================================================================
+ * M01_MasterData_UI_LogicLab_Side.ts
+ * 로직 상세 오른쪽 두 패널 — 「흐름도」(다이어그램 · 상세 내용 = M02_DF_Panel) · 「원문」(품셈 본문 절)
+ * 둘 중 하나만 열림(하나 열면 다른 하나 접힘) · 둘 다 접기 됨 · 접힌 패널 = 얇은 띠(머리 단추 그대로)
+ * 열린 패널은 계정 취향(`m01-logic-panel`)으로 기억 · 원문은 출처 글로 서버가 찾음(`GET /m01/logic/source`)
+ * ========================================================================== */
+
+import { currentLanguageIndex } from "@ui/ui_template_locale";
+import { createButton, el } from "@ui/ui_template_elements";
+import { API_BASE_URL } from "@config/config_frontend";
+import { readStateRaw, writeStateRaw } from "../A00_Common/b_page_state";
+import type { SplitHandle } from "./M01_MasterData_UI_LogicLab_Flow";
+import "../M02_MasterTemplete/DataFlow/M02_DF_Panel.css";
+import "./M01_MasterData_UI_LogicLab_Side.css";
+
+const TEXT = {
+  Toggle: ["원문", "Source"],
+  Open: ["원문 펴기", "Open the source panel"],
+  Close: ["원문 접기", "Collapse the source panel"],
+  Loading: ["원문 찾는 중", "Looking up the source"],
+  None: ["원문 연결 없음", "No linked source"],
+  From: ["출처", "Source"],
+  NoSource: ["출처 없음", "No source"],
+  Near: ["{v} 절이 없어 위 절", "No {v} section — showing the parent"],
+} as const;
+
+const ts = (key: keyof typeof TEXT, v = ""): string =>
+  TEXT[key][currentLanguageIndex === 1 ? 1 : 0].replace("{v}", v);
+
+/** 접힌 띠 너비 — M02_DF_Panel 의 STRIP_WIDTH 와 같음(패널 모듈은 늦게 받으므로 따로 둠) */
+const STRIP = 40;
+
+export type PanelPick = "flow" | "source" | "none";
+
+interface Block {
+  h?: number;
+  text?: string;
+  p?: string;
+  table?: string[][];
+}
+interface Found {
+  number: string;
+  matched: string;
+  file: string;
+  blocks: Block[];
+}
+
+export interface LogicSide {
+  /** 흐름도 패널에 넘길 칸 — right = 흐름도 자리 · setRight = 흐름도 패널이 알린 너비 */
+  flowSplit: SplitHandle;
+  flowFolded(): boolean;
+  pick(next: PanelPick): void;
+  /** 흐름도 패널이 뜨면 접기 함수 · 내리면 null */
+  bindFlow(fold: ((on: boolean) => void) | null): void;
+  /** 연 로직의 출처 글 — 원문 패널이 열려 있으면 찾음 */
+  showSource(src: string): void;
+}
+
+const readPick = (): PanelPick => {
+  const got = readStateRaw("m01-logic-panel");
+  return got === "source" || got === "none" ? got : "flow";
+};
+
+function blockNode(b: Block): HTMLElement {
+  if (b.table)
+    return el("div", {
+      className: "m01-logic__scroll",
+      children: [
+        el("table", {
+          className: "m01-logic__grid m01lab-src__table",
+          children: [
+            el("tbody", {
+              children: b.table.map((r) =>
+                el("tr", { children: r.map((c) => el("td", { text: c })) }),
+              ),
+            }),
+          ],
+        }),
+      ],
+    });
+  if (b.h) return el("h4", { className: "m01lab-src__head", text: b.text ?? "" });
+  return el("p", { className: "m01lab-src__p", text: b.p ?? "" });
+}
+
+export function buildLogicSide(split: SplitHandle): LogicSide {
+  const flowSlot = el("div", { className: "m01lab-side__slot" });
+  const body = el("div", { className: "m01lab-src__body" });
+  const title = el("strong", { className: "m02-dfp__title" });
+  const toggle = createButton({
+    label: ts("Toggle"),
+    size: "sm",
+    variant: "ghost",
+    onClick: () => pick(now === "source" ? "none" : "source"),
+  });
+  toggle.classList.add("m02-dfp__toggle");
+  const head = el("header", { className: "m02-dfp__head", children: [toggle, title] });
+  const open = el("div", { className: "m02-dfp__open", children: [head, body] });
+  const strip = el("div", { className: "m02-dfp__strip" });
+  const source = el("aside", { className: "m02-dfp m01lab-src", children: [open, strip] });
+  const sourceSlot = el("div", { className: "m01lab-side__slot", children: [source] });
+  split.right.replaceChildren(
+    el("div", { className: "m01lab-side", children: [flowSlot, sourceSlot] }),
+  );
+
+  let now = readPick();
+  let flowPx: number | null = null;
+  let flowFold: ((on: boolean) => void) | null = null;
+  let want = "";
+  let shown: string | null = null;
+
+  /** 칸 너비 — 원문(또는 흐름도가 아직 안 뜸) = 두 칸 비율 · 흐름도 = 패널 너비 + 띠 · 둘 다 접힘 = 띠 둘 */
+  const width = (): void =>
+    split.setRight(
+      now === "source" || (now === "flow" && flowPx === null)
+        ? null
+        : now === "flow"
+          ? (flowPx ?? 0) + STRIP
+          : STRIP * 2,
+    );
+
+  const load = (): void => {
+    if (now !== "source" || shown === want) return;
+    const src = (shown = want);
+    title.textContent = src || ts("NoSource");
+    body.replaceChildren(el("p", { className: "m01-logic__muted", text: ts("Loading") }));
+    const none = (): void =>
+      body.replaceChildren(
+        el("p", { className: "m01lab-src__none", text: ts("None") }),
+        el("p", { className: "m01-logic__muted", text: `${ts("From")} · ${src || "—"}` }),
+      );
+    if (!src.trim()) return none();
+    void fetch(`${API_BASE_URL}/m01/logic/source?${new URLSearchParams({ src })}`, {
+      credentials: "include",
+    })
+      .then((r) => (r.ok ? (r.json() as Promise<{ found: Found[] }>) : { found: [] }))
+      .catch(() => ({ found: [] as Found[] }))
+      .then(({ found }) => {
+        if (shown !== src) return;
+        if (!found.length) return none();
+        body.replaceChildren(
+          ...found.flatMap((f) => [
+            el("p", {
+              className: "m01-logic__muted m01lab-src__file",
+              text: f.matched === f.number ? f.file : `${f.file} · ${ts("Near", f.number)}`,
+            }),
+            ...f.blocks.map(blockNode),
+          ]),
+        );
+      });
+  };
+
+  const fold = (on: boolean): void => {
+    open.hidden = on;
+    strip.hidden = !on;
+    (on ? strip : head).prepend(toggle);
+    toggle.setAttribute("aria-expanded", String(!on));
+    toggle.title = ts(on ? "Open" : "Close");
+  };
+
+  const pick = (next: PanelPick): void => {
+    if (next !== now) writeStateRaw("m01-logic-panel", next);
+    now = next;
+    flowFold?.(now !== "flow"); // 칸을 줄이기 전에 — 흐름도 패널이 접기 전 너비를 재어 둠
+    flowSlot.classList.toggle("is-open", now === "flow");
+    sourceSlot.classList.toggle("is-open", now === "source");
+    fold(now !== "source");
+    width();
+    load();
+  };
+
+  pick(now);
+  return {
+    flowSplit: {
+      root: split.root,
+      right: flowSlot,
+      setRight: (px) => {
+        flowPx = px;
+        width();
+      },
+    },
+    flowFolded: () => now !== "flow",
+    pick,
+    bindFlow: (f) => {
+      flowFold = f;
+    },
+    showSource: (src) => {
+      want = src;
+      load();
+    },
+  };
+}
diff --git a/M02_MasterTemplete/DataFlow/M02_DF_Panel.ts b/M02_MasterTemplete/DataFlow/M02_DF_Panel.ts
index 1d2c68ee0..6462690e5 100644
--- a/M02_MasterTemplete/DataFlow/M02_DF_Panel.ts
+++ b/M02_MasterTemplete/DataFlow/M02_DF_Panel.ts
@@ -41,6 +41,9 @@ export interface FlowPanelOpts {
   logics?(key: string): Promise<CfLogic | null>;
   /** 패널 너비가 바뀜(끌기 · 접기 · 펴기) — 부르는 쪽이 칸 너비를 맞춤 */
   onResize?(px: number): void;
+  /** 접힘을 부르는 쪽이 정함(처음 값) — 주면 접기 단추는 onFold 만 부르고 기억도 부르는 쪽 몫 */
+  folded?: boolean;
+  onFold?(on: boolean): void;
 }
 
 export interface FlowPanel {
@@ -49,6 +52,8 @@ export interface FlowPanel {
   destroy(): void;
   /** 크게 보기 열기 */
   expand(): void;
+  /** 밖에서 접기 · 펴기(onFold 를 부르지 않음) */
+  fold(on: boolean): void;
 }
 
 /* ── 너비(DOM 없음) ─────────────────────────────────────────────────── */
@@ -105,8 +110,9 @@ export function mountFlowPanel(host: HTMLElement, opts: FlowPanelOpts): FlowPane
   });
   const { diagram, detail, summary, note, undo } = paper.parts;
   let width = storedWidth(readStore(WIDTH_KEY));
-  let folded = readStore(FOLD_KEY) === "1";
-  const tell = (): void => opts.onResize?.(folded ? STRIP_WIDTH : (width ?? host.clientWidth));
+  let folded = opts.folded ?? readStore(FOLD_KEY) === "1";
+  const tell = (): void =>
+    opts.onResize?.(folded ? STRIP_WIDTH : (width ?? Math.max(PANEL_MIN, host.clientWidth)));
 
   const sm = (label: string, onClick: () => void, variant: "ghost" | "filled" = "ghost") =>
     createButton({ label, size: "sm", variant, onClick });
@@ -116,7 +122,7 @@ export function mountFlowPanel(host: HTMLElement, opts: FlowPanelOpts): FlowPane
     label: tf("Toggle"),
     size: "sm",
     variant: "ghost",
-    onClick: () => setFolded(!folded),
+    onClick: () => (opts.onFold ? opts.onFold(!folded) : setFolded(!folded)),
   });
   toggle.classList.add("m02-dfp__toggle");
   const head = el("header", {
@@ -215,7 +221,7 @@ export function mountFlowPanel(host: HTMLElement, opts: FlowPanelOpts): FlowPane
     if (on && !folded && width === null && root.isConnected)
       width = Math.round(root.getBoundingClientRect().width);
     folded = on;
-    writeStore(FOLD_KEY, on ? "1" : "0");
+    if (!opts.onFold) writeStore(FOLD_KEY, on ? "1" : "0");
     root.classList.toggle("is-folded", on);
     open.hidden = on;
     strip.hidden = !on;
@@ -290,5 +296,6 @@ export function mountFlowPanel(host: HTMLElement, opts: FlowPanelOpts): FlowPane
       root.remove();
     },
     expand,
+    fold: (on) => on !== folded && setFolded(on),
   };
 }
diff --git a/resources/tester/test_m01_logic_source.py b/resources/tester/test_m01_logic_source.py
new file mode 100644
index 000000000..75d2dab56
--- /dev/null
+++ b/resources/tester/test_m01_logic_source.py
@@ -0,0 +1,55 @@
+"""M01 로직 원문 — 출처 글 → 품셈 본문 절(44-4). 원본은 읽기만."""
+
+from __future__ import annotations
+
+import json
+
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+from M01_MasterData import M01_MasterData_Router as router_module
+from M01_MasterData import M01_MasterData_Store as store
+from M01_MasterData import M01_MasterData_Store_Make as make
+
+
+def test_build_civil_section_with_table() -> None:
+    got = make.source("건설품셈 토목 1-1-2")
+    assert len(got["found"]) == 1
+    one = got["found"][0]
+    assert one["matched"] == "1-1-2"
+    assert one["file"].startswith("원가계산/건설공사_표준품셈/본문/02_토목부문/제01장_")
+    assert one["blocks"][0]["h"] == 3 and one["blocks"][0]["text"].startswith("1-1-2 유도선")
+    table = next(b["table"] for b in one["blocks"] if "table" in b)
+    assert table[0][0] == "구분" and ["특별인부", "인", "2", "1,350", "1,560"] in table
+    # 다음 절(1-1-3 …) 앞에서 끊김 · 주석 줄 뺌
+    assert not any("1-1-3" in b.get("text", "") for b in one["blocks"])
+    assert not any(b.get("p", "").startswith("<!--") for b in one["blocks"])
+
+
+def test_forest_and_many_numbers() -> None:
+    forest = make.source("산림품셈 3-4-2 1")["found"]
+    assert [x["matched"] for x in forest] == ["3-4-2"]
+    many = make.source("건설품셈 공통 8-1-5 · 8-1-6")["found"]
+    assert [x["number"] for x in many] == ["8-1-5", "8-1-6"]
+
+
+def test_no_link() -> None:
+    assert make.source("현장 자체 단가")["found"] == []
+    assert make.source("건설품셈 토목 99-9-9")["found"] == []
+
+
+def test_most_master_logics_link() -> None:
+    """정본 로직 출처 대부분이 원문 절에 닿음."""
+    hit = total = 0
+    for path in store.FOLDER.glob("로직_*품셈_*.json"):
+        for row in json.loads(path.read_text(encoding="utf-8"))["줄"]:
+            total += 1
+            hit += bool(make.source(row.get("출처", ""))["found"])
+    assert total > 1000 and hit / total > 0.9, (hit, total)
+
+
+def test_route() -> None:
+    app = FastAPI()
+    app.include_router(router_module.router)
+    got = TestClient(app).get("/api/m01/logic/source", params={"src": "산림품셈 3-1"}).json()
+    assert got["found"][0]["matched"] == "3-1"
diff --git a/resources/tester/ui_checks/44-4_로직상세_패널.js b/resources/tester/ui_checks/44-4_로직상세_패널.js
new file mode 100644
index 000000000..682c0204e
--- /dev/null
+++ b/resources/tester/ui_checks/44-4_로직상세_패널.js
@@ -0,0 +1,103 @@
+/* 44-4 M01 단가산출 로직 상세 — `orca eval --expression "$(cat 이 파일)"` 한 번에 돎 · JSON 돌려줌.
+ *
+ * 시작 화면: M01 마스터 데이터(#/m01-master-data · 시스템 관리자 로그인) · 아무 화면이나.
+ *   로직 GC000277(건설품셈 토목 1-1-2 유도선 설치 및 해체)을 엶 · 고치지 않음 · 끝에 패널 취향을 처음 값으로 되돌림.
+ * 기대 수치:
+ *   order = ["기본정보","시험 계산","단가산출 상세","텍스트 수식"](흐름 로직이면 셋째 · 넷째는 흐름 보기 안)
+ *   flow  = {flow:true, source:false, pref:"flow"} · 오른쪽 칸 너비 > 300
+ *   source = {flow:false, source:true, pref:"source"} · srcHead 에 「1-1-2 유도선」 · srcTable 에 「특별인부」
+ *   none  = {flow:false, source:false, pref:"none"} · 오른쪽 칸 너비 = 80(띠 둘)
+ *   back  = {flow:true, source:false, pref:"flow"}(흐름도 띠 단추로 다시 폄)
+ *   noLink = 「원문 연결 없음」 + 「출처 · …」(서버가 빈 목록을 줄 때 · fetch 를 잠시 바꿔 봄)
+ *   restored = 처음 취향 값
+ */
+(async () => {
+  const W = (ms) => new Promise((r) => setTimeout(r, ms));
+  const $ = (s, root = document) => root.querySelector(s);
+  const $$ = (s, root = document) => [...root.querySelectorAll(s)];
+  const until = async (f, ms = 15000) => {
+    for (let t = 0; t < ms; t += 200) {
+      const v = f();
+      if (v) return v;
+      await W(200);
+    }
+    return null;
+  };
+  const PREF = "aislo:pref:m01-logic-panel";
+  const first = localStorage.getItem(PREF);
+  const out = {};
+  const openLogic = async (key) => {
+    sessionStorage.setItem("m01.logic.pending", key);
+    // 왼쪽 「단가산출 로직」 컨테이너 제목 — 펼칠 때 로직 화면으로(펼쳐져 있으면 접었다 폄)
+    const tab = $$(".ui-collapsible__title").find((h) => h.innerText.trim() === "단가산출 로직");
+    if (!tab) return false;
+    if (!tab.closest(".ui-collapsible").classList.contains("is-collapsed")) tab.click();
+    tab.click();
+    return until(() => {
+      const t = $(".m02-dfp__title")?.innerText ?? "";
+      return !$(".m01lab-flow")?.hidden && $(".m01lab-side .m02-dfp") && t && t !== "";
+    });
+  };
+  if (!(await openLogic("GC000277"))) return JSON.stringify({ error: "로직 못 엶" });
+  await W(800);
+  out.order = $$(".m01lab-flow__left .m01lab__box > .m01-logic__section-head h3").map((h) =>
+    h.innerText.trim(),
+  );
+  const slots = () => $$(".m01lab-side__slot");
+  const state = () => ({
+    flow:
+      slots()[0].classList.contains("is-open") &&
+      !$(".m02-dfp", slots()[0]).classList.contains("is-folded"),
+    source: slots()[1].classList.contains("is-open") && !$(".m02-dfp__open", slots()[1]).hidden,
+    pref: localStorage.getItem(PREF),
+    width: Math.round($(".m01lab-flow__right").getBoundingClientRect().width),
+  });
+  const flowToggle = () => $(".m02-dfp__toggle", slots()[0]);
+  const srcToggle = () => $(".m02-dfp__toggle", slots()[1]);
+  // 처음 = 흐름도 열림으로 맞춤
+  if (!state().flow) {
+    if (state().source) srcToggle().click();
+    await W(100);
+    flowToggle().click();
+    await W(400);
+  }
+  out.flow = state();
+  srcToggle().click();
+  await until(() => $(".m01lab-src__head"));
+  out.source = state();
+  out.srcHead = $(".m01lab-src__head")?.innerText;
+  out.srcFile = $(".m01lab-src__file")?.innerText;
+  out.srcTable = $$(".m01lab-src__table td").some((td) => td.innerText === "특별인부");
+  srcToggle().click();
+  await W(400);
+  out.none = state();
+  flowToggle().click();
+  await W(600);
+  out.back = state();
+  // 원문 연결 없음 — 서버가 빈 목록을 줄 때
+  srcToggle().click();
+  const real = window.fetch;
+  window.fetch = (u, o) =>
+    String(u).includes("/m01/logic/source")
+      ? Promise.resolve(new Response(JSON.stringify({ found: [] }), { status: 200 }))
+      : real(u, o);
+  try {
+    await openLogic("GC000338");
+    await until(() => $(".m01lab-src__none"));
+    out.noLink = [
+      $(".m01lab-src__none")?.innerText,
+      $(".m01lab-src__body .m01-logic__muted")?.innerText,
+    ];
+  } finally {
+    window.fetch = real;
+  }
+  // 되돌림 — 처음 취향(없으면 흐름도)
+  const want = first ?? "flow";
+  if (want !== "source") srcToggle().click();
+  await W(200);
+  if (want === "flow") flowToggle().click();
+  await W(300);
+  out.restored = localStorage.getItem(PREF) ?? "flow";
+  out.first = first;
+  return JSON.stringify(out);
+})();