diff --git a/M01_MasterData/SheetLogic/M01_SL_Panel.css b/M01_MasterData/SheetLogic/M01_SL_Panel.css
new file mode 100644
index 000000000..d67df74d1
--- /dev/null
+++ b/M01_MasterData/SheetLogic/M01_SL_Panel.css
@@ -0,0 +1,172 @@
+.m01-slpanel {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-8);
+  font-size: var(--text-body);
+  color: var(--color-text-body);
+}
+
+.m01-slpanel-head,
+.m01-slpanel-row {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  gap: var(--spacing-8);
+}
+
+.m01-slpanel-bar {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-8);
+}
+
+.m01-slpanel-cell {
+  padding: 2px var(--spacing-12);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-pills);
+  background: var(--color-surface-raised);
+}
+
+.m01-slpanel-note {
+  color: var(--color-text-muted);
+  font-size: var(--text-body-sm);
+}
+
+.m01-slpanel .ui-btn,
+.m01-slpanel .ui-input {
+  min-height: 44px;
+  font-size: var(--text-body);
+}
+
+.m01-slpanel-name {
+  flex: none;
+  width: 12em;
+}
+
+.m01-slpanel-msg {
+  margin: 0;
+  padding: var(--spacing-8) var(--spacing-12);
+  border-left: 4px solid var(--color-warning);
+  background: var(--color-surface-raised);
+  font-weight: var(--font-weight-medium);
+}
+
+.m01-slpanel-sheet {
+  position: relative;
+  min-height: 260px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-cards);
+  overflow: hidden;
+}
+
+.m01-slpanel-pills {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--spacing-8);
+}
+
+.m01-slpanel-pill,
+.m01-slpanel-dir {
+  min-height: 44px;
+  padding: 0 var(--spacing-12);
+  border: 2px solid;
+  border-radius: var(--radius-pills);
+  background: var(--color-surface);
+  color: inherit;
+  font: inherit;
+  font-weight: var(--font-weight-medium);
+  cursor: pointer;
+}
+
+.m01-slpanel-dir {
+  display: inline-flex;
+  align-items: center;
+  min-height: 0;
+  cursor: default;
+}
+
+.m01-slpanel-pill:focus-visible {
+  outline: 2px solid var(--color-focus-ring);
+}
+
+.m01-slpanel-pill.is-on {
+  background: var(--color-surface-raised);
+  font-weight: var(--font-weight-bold);
+}
+
+.is-in {
+  border-color: #3b82f6;
+}
+
+.is-out {
+  border-color: #f59e0b;
+}
+
+.m01-slpanel-info {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-4);
+  padding: var(--spacing-12);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-cards);
+  background: var(--color-surface-raised);
+}
+
+.m01-slpanel-infoline {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--spacing-8);
+}
+
+.m01-slpanel-infoline > .m01-slpanel-note {
+  min-width: 6em;
+}
+
+/* 칸 위 알약 표시 — 색 + 글자(입력 · 출력) 둘 다 */
+.m01-slpanel .aislo-cell[data-sl-pill="in"] {
+  box-shadow: inset 0 0 0 2px #3b82f6;
+}
+
+.m01-slpanel .aislo-cell[data-sl-pill="out"] {
+  box-shadow: inset 0 0 0 2px #f59e0b;
+}
+
+.m01-slpanel .aislo-cell[data-sl-pill]::after {
+  content: attr(data-sl-name);
+  position: absolute;
+  top: 0;
+  right: 0;
+  padding: 0 4px;
+  border-radius: 0 0 0 6px;
+  background: var(--color-surface);
+  color: var(--color-text);
+  font-size: 10px;
+  line-height: 14px;
+  pointer-events: none;
+}
+
+.m01-slpanel .aislo-cell[data-sl-pill="in"]::after {
+  border: 1px solid #3b82f6;
+}
+
+.m01-slpanel .aislo-cell[data-sl-pill="out"]::after {
+  border: 1px solid #f59e0b;
+}
+
+.m01-slpanel .aislo-cell[data-sl-lock]::before {
+  content: "🔒 " attr(data-sl-lock);
+  position: absolute;
+  bottom: 0;
+  left: 0;
+  padding: 0 4px;
+  background: var(--color-surface);
+  color: var(--color-text);
+  font-size: 10px;
+  line-height: 14px;
+  pointer-events: none;
+}
+
+.m01-slpanel .aislo-cell[data-sl-err] {
+  outline: 2px dashed var(--color-danger);
+  outline-offset: -2px;
+}
diff --git a/M01_MasterData/SheetLogic/M01_SL_Panel.ts b/M01_MasterData/SheetLogic/M01_SL_Panel.ts
new file mode 100644
index 000000000..f2a4c112f
--- /dev/null
+++ b/M01_MasterData/SheetLogic/M01_SL_Panel.ts
@@ -0,0 +1,544 @@
+/* =============================================================================
+ * M01_SL_Panel.ts
+ * 시트 로직 아래 시트 판 — 고른 상자의 시트를 우리 스프레드시트 편집기로 · 칸 → 입력/출력 알약 · 칸 위 알약 표시 ·
+ * 받는 알약 칸 잠금 · 틀 단추(진짜 엑셀 수식) · 틀린 수식/안 이어진 입력 알약 한 줄
+ * 모양은 `docs/raw/M01_쉬운단가/시트로직_정함.md` · M01_SL_Model 타입 그대로 · 편집기는 M02 미리보기가 쓰는 그것(늦게 불러옴)
+ * 글 [한, 영] 짝은 아래 TEXT
+ * ========================================================================== */
+
+import { currentLanguageIndex } from "@ui/ui_template_locale";
+import { createButton, el, showConfirmDialog, showToast } from "@ui/ui_template_elements";
+import type {
+  CalcValue,
+  CalcValues,
+  SpreadsheetHandle,
+  Workbook,
+} from "../../A00_Common/spreadsheet/spreadsheet";
+import { disconnect, type SheetLogic, type SlEdge, type SlNode, type SlPill } from "./M01_SL_Model";
+import "./M01_SL_Panel.css";
+
+const TEXT = {
+  Cell: ["고른 칸", "Selected cell"],
+  PillIn: ["입력 알약으로", "Make input pill"],
+  PillOut: ["출력 알약으로", "Make output pill"],
+  AskName: ["알약 이름", "Pill name"],
+  Ok: ["정함", "Set"],
+  Cancel: ["취소", "Cancel"],
+  Frames: ["틀", "Templates"],
+  FrameMore: ["할증", "Markup"],
+  FrameDiv: ["나누기", "Divide"],
+  FrameIf: ["만약", "If"],
+  FrameMin: ["최소", "Min"],
+  FrameMax: ["최대", "Max"],
+  FrameUp: ["올림", "Round up"],
+  FrameLook: ["표에서 찾기", "Look up in table"],
+  FrameHint: ["칸 주소만 바꾸면 됨", "Just change the cell addresses"],
+  In: ["입력", "In"],
+  Out: ["출력", "Out"],
+  Lock: ["선", "Wire"],
+  Pills: ["알약", "Pills"],
+  NoPills: [
+    "아직 알약이 없음 — 칸을 골라 알약으로 정함",
+    "No pills yet — pick a cell and make it a pill",
+  ],
+  Value: ["값", "Value"],
+  Unit: ["단위", "Unit"],
+  From: ["어디서 오나", "Comes from"],
+  To: ["어디로 가나", "Goes to"],
+  NoFrom: ["아직 이어지지 않음", "Not connected yet"],
+  NoTo: ["아직 어디로도 안 감", "Goes nowhere yet"],
+  Close: ["닫기", "Close"],
+  ReadOnly: ["표준은 읽기만", "Read only"],
+  Loading: ["시트를 불러오는 중", "Loading sheet"],
+  BreakAsk: [
+    "이 칸은 선으로 들어오는 값입니다. 선을 끊고 직접 고칠까요?",
+    "This cell receives a wire. Cut the wire and edit it yourself?",
+  ],
+  BreakOk: ["선을 끊고 고침", "Cut and edit"],
+  Cannot: ["이 고침은 지금 할 수 없음", "This change cannot be made now"],
+  Problem: ["⚠ ", "⚠ "],
+  Unwired: [" 입력 알약이 아직 이어지지 않음", " input pill is not connected yet"],
+  Err_DIV0: ["0으로 나눔", "divides by zero"],
+  Err_NAME: ["알 수 없는 이름", "unknown name"],
+  Err_REF: ["없는 칸을 가리킴", "points to a missing cell"],
+  Err_VALUE: ["값 종류가 안 맞음", "wrong kind of value"],
+  Err_CYCLE: ["서로 돌려 가리킴(순환)", "circular reference"],
+  Err_NA: ["찾는 값이 없음", "value not found"],
+  Err_OTHER: ["수식이 틀림", "formula is wrong"],
+} as const;
+
+const tp = (key: keyof typeof TEXT): string => TEXT[key][currentLanguageIndex];
+
+/** 틀 단추 — 진짜 엑셀 수식을 고른 칸에 넣음 */
+const FRAMES: [keyof typeof TEXT, string][] = [
+  ["FrameMore", "=B1*(1+B2/100)"],
+  ["FrameDiv", "=B1/B2"],
+  ["FrameIf", '=IF(B3="급",10,0)'],
+  ["FrameMin", "=MIN(B1,B2)"],
+  ["FrameMax", "=MAX(B1,B2)"],
+  ["FrameUp", "=ROUNDUP(B4,3)"],
+  ["FrameLook", "=XLOOKUP(B1,E1:E10,F1:F10)"],
+];
+
+const ERR_KEY: Record<string, keyof typeof TEXT> = {
+  "#DIV/0!": "Err_DIV0",
+  "#NAME?": "Err_NAME",
+  "#REF!": "Err_REF",
+  "#VALUE!": "Err_VALUE",
+  "#CYCLE!": "Err_CYCLE",
+  "#N/A": "Err_NA",
+};
+
+type Handlers = {
+  change(sl: SheetLogic): void;
+  pill(nodeId: string, cell: string, dir: "in" | "out", name: string): void;
+};
+type SheetModule = typeof import("../../A00_Common/spreadsheet/spreadsheet");
+
+interface State {
+  nodeId: string;
+  sl: SheetLogic;
+  on: Handlers;
+  readOnly: boolean;
+  handle: SpreadsheetHandle | null;
+  /** 수식 칸 계산값 — 바뀐 뒤에만 새로 받음(받으면 격자가 다시 그려져, 표시 쪽에서 부르면 맴돎) */
+  snap: CalcValues;
+  /** 편집기가 마지막으로 낸 문서(활성 빼고) — 같으면 다시 안 끼움 */
+  json: string;
+  cell: string;
+  info: { dir: "in" | "out"; name: string } | null;
+  asking: "in" | "out" | null;
+  busy: boolean;
+  parts: {
+    cell: HTMLElement;
+    bar: HTMLElement;
+    msg: HTMLElement;
+    sheet: HTMLElement;
+    pills: HTMLElement;
+    info: HTMLElement;
+  };
+  observer: MutationObserver | null;
+  redraw(): void;
+}
+
+const states = new WeakMap<HTMLElement, State>();
+let sheetModule: Promise<SheetModule> | null = null;
+/** 편집기는 M02 처럼 늦게 불러옴 — 정적 import 금지 */
+const loadSheet = (): Promise<SheetModule> =>
+  (sheetModule ??= import("../../A00_Common/spreadsheet/spreadsheet"));
+
+const norm = (book: Workbook): string => JSON.stringify({ ...book, 활성: null, 계산값: null });
+const nodeOf = (st: State): SlNode | undefined => st.sl.nodes.find((n) => n.id === st.nodeId);
+const shown = (st: State): Workbook => ({
+  ...st.sl.workbook,
+  활성: nodeOf(st)?.sheetId ?? st.sl.workbook.활성,
+});
+
+/* ------------------------------ 값 · 말 ------------------------------ */
+
+function valueText(v: CalcValue | number | string | boolean | undefined | null): string {
+  if (v === undefined || v === null) return "";
+  if (typeof v !== "object") return String(v);
+  if ("수" in v) return v.수;
+  if ("글" in v) return v.글;
+  if ("참" in v) return v.참 ? "TRUE" : "FALSE";
+  return v.오류;
+}
+
+function valueAt(st: State, addr: string): string {
+  const node = nodeOf(st);
+  const sheet = st.sl.workbook.시트.find((s) => s.id === node?.sheetId);
+  const cell = sheet?.칸[addr];
+  if (!cell) return "";
+  if (cell.식 === undefined) return valueText(cell.값);
+  return valueText(st.snap[sheet!.id]?.[addr]);
+}
+
+const edgesIn = (st: State, pill: string): SlEdge[] =>
+  st.sl.edges.filter((e) => e.to.node === st.nodeId && e.to.pill === pill);
+const edgesOut = (st: State, pill: string): SlEdge[] =>
+  st.sl.edges.filter((e) => e.from.node === st.nodeId && e.from.pill === pill);
+
+/** 선으로 값을 받는 칸 — 직접 고치기 전에 물음 */
+function lockedCells(st: State): Map<string, SlEdge> {
+  const out = new Map<string, SlEdge>();
+  for (const p of nodeOf(st)?.pillsIn ?? []) {
+    const e = edgesIn(st, p.name)[0];
+    if (e) out.set(p.cell, e);
+  }
+  return out;
+}
+
+/** 틀린 수식 · 이어지지 않은 입력 알약 — 칸 → 까닭 */
+function problems(st: State): Map<string, string> {
+  const out = new Map<string, string>();
+  const node = nodeOf(st);
+  if (!node || !st.handle) return out;
+  const sheet = st.sl.workbook.시트.find((s) => s.id === node.sheetId);
+  const snap = st.snap[node.sheetId] ?? {};
+  for (const [addr, v] of Object.entries(snap)) {
+    if (typeof v === "object" && "오류" in v) {
+      out.set(addr, `${addr} ${tp(ERR_KEY[v.오류] ?? "Err_OTHER")}`);
+    }
+  }
+  for (const p of node.pillsIn) {
+    const filled = sheet?.칸[p.cell]?.식 !== undefined;
+    if (!edgesIn(st, p.name).length && !filled && node.kind !== "input" && node.kind !== "const") {
+      out.set(p.cell, `${p.name}(${p.cell})${tp("Unwired")}`);
+    }
+  }
+  return out;
+}
+
+/** 계산값 새로 받고 표시 다시 — 편집기가 바뀐 뒤 · 처음 뜬 뒤에만 */
+function refreshSnap(st: State): void {
+  if (!st.handle) return;
+  st.snap = st.handle.recalc();
+  st.redraw();
+}
+
+/* ------------------------------ 칸 위 표시 ------------------------------ */
+
+function applyMarks(st: State): void {
+  const node = nodeOf(st);
+  const grid = st.parts.sheet;
+  if (!node) return;
+  const pill = new Map<string, { dir: "in" | "out"; p: SlPill }>();
+  for (const p of node.pillsIn) pill.set(p.cell, { dir: "in", p });
+  for (const p of node.pillsOut) pill.set(p.cell, { dir: "out", p });
+  const lock = lockedCells(st);
+  const bad = problems(st);
+  for (const c of grid.querySelectorAll<HTMLElement>(".aislo-cell")) {
+    const addr = c.dataset.addr ?? "";
+    const hit = pill.get(addr);
+    for (const a of ["slPill", "slName", "slLock", "slErr"]) delete c.dataset[a];
+    if (hit) {
+      c.dataset.slPill = hit.dir;
+      c.dataset.slName = `${tp(hit.dir === "in" ? "In" : "Out")} ${hit.p.name}`;
+    }
+    if (lock.has(addr)) c.dataset.slLock = tp("Lock");
+    if (bad.has(addr)) c.dataset.slErr = "1";
+  }
+  const first = [...bad.values()][0];
+  st.parts.msg.textContent = first
+    ? `${tp("Problem")}${first}${bad.size > 1 ? ` (+${bad.size - 1})` : ""}`
+    : "";
+  st.parts.msg.hidden = !first;
+}
+
+/* ------------------------------ 위 줄 · 알약 목록 ------------------------------ */
+
+function nameDefault(st: State): string {
+  const row = st.cell.replace(/^[A-Z]+/, "");
+  const sheet = st.sl.workbook.시트.find((s) => s.id === nodeOf(st)?.sheetId);
+  const a = sheet?.칸[`A${row}`];
+  return a ? valueText(a.값 ?? a.식) : "";
+}
+
+function drawBar(st: State): void {
+  const { bar, cell } = st.parts;
+  cell.textContent = `${tp("Cell")} ${st.cell}`;
+  const frag: (HTMLElement | string)[] = [];
+  if (st.readOnly) {
+    bar.replaceChildren(el("span", { className: "m01-slpanel-note", text: tp("ReadOnly") }));
+    return;
+  }
+  const ask = (dir: "in" | "out"): void => {
+    st.asking = dir;
+    drawBar(st);
+  };
+  const pillRow = el("div", {
+    className: "m01-slpanel-row",
+    children: [
+      createButton({ label: tp("PillIn"), variant: "ghost", size: "sm", onClick: () => ask("in") }),
+      createButton({
+        label: tp("PillOut"),
+        variant: "ghost",
+        size: "sm",
+        onClick: () => ask("out"),
+      }),
+    ],
+  });
+  frag.push(pillRow);
+  if (st.asking) {
+    const dir = st.asking;
+    const input = el("input", {
+      className: "ui-input m01-slpanel-name",
+      attrs: { type: "text", "aria-label": tp("AskName") },
+    });
+    input.value = nameDefault(st);
+    const done = (): void => {
+      const name = input.value.trim();
+      if (!name) return;
+      st.asking = null;
+      st.on.pill(st.nodeId, st.cell, dir, name);
+      drawBar(st);
+    };
+    input.addEventListener("keydown", (e) => e.key === "Enter" && done());
+    frag.push(
+      el("div", {
+        className: "m01-slpanel-row",
+        children: [
+          el("span", {
+            className: `m01-slpanel-dir is-${dir}`,
+            text: tp(dir === "in" ? "In" : "Out"),
+          }),
+          input,
+          createButton({ label: tp("Ok"), variant: "filled", size: "sm", onClick: done }),
+          createButton({
+            label: tp("Cancel"),
+            variant: "ghost",
+            size: "sm",
+            onClick: () => ((st.asking = null), drawBar(st)),
+          }),
+        ],
+      }),
+    );
+    queueMicrotask(() => input.focus());
+  }
+  frag.push(
+    el("div", {
+      className: "m01-slpanel-row",
+      children: [
+        el("span", { className: "m01-slpanel-note", text: tp("Frames") }),
+        ...FRAMES.map(([key, formula]) =>
+          createButton({
+            label: tp(key),
+            variant: "ghost",
+            size: "sm",
+            onClick: () => putFormula(st, formula),
+          }),
+        ),
+        el("span", { className: "m01-slpanel-note", text: tp("FrameHint") }),
+      ],
+    }),
+  );
+  bar.replaceChildren(...frag.filter((x): x is HTMLElement => typeof x !== "string"));
+}
+
+function drawPills(st: State): void {
+  const node = nodeOf(st);
+  const chips: HTMLElement[] = [];
+  const add = (dir: "in" | "out", p: SlPill): void => {
+    const b = el("button", {
+      className: `m01-slpanel-pill is-${dir}${st.info?.name === p.name && st.info.dir === dir ? " is-on" : ""}`,
+      text: `${tp(dir === "in" ? "In" : "Out")} · ${p.name} (${p.cell})`,
+      attrs: { type: "button" },
+    });
+    b.addEventListener("click", () => ((st.info = { dir, name: p.name }), drawPills(st)));
+    chips.push(b);
+  };
+  for (const p of node?.pillsIn ?? []) add("in", p);
+  for (const p of node?.pillsOut ?? []) add("out", p);
+  st.parts.pills.replaceChildren(
+    ...(chips.length
+      ? chips
+      : [el("span", { className: "m01-slpanel-note", text: tp("NoPills") })]),
+  );
+  drawInfo(st);
+}
+
+function drawInfo(st: State): void {
+  const box = st.parts.info;
+  const node = nodeOf(st);
+  const p = (st.info?.dir === "in" ? node?.pillsIn : node?.pillsOut)?.find(
+    (x) => x.name === st.info?.name,
+  );
+  if (!st.info || !p || !node) {
+    box.hidden = true;
+    box.replaceChildren();
+    return;
+  }
+  const dir = st.info.dir;
+  const nameOf = (id: string): string => st.sl.nodes.find((n) => n.id === id)?.name ?? "";
+  const links = (dir === "in" ? edgesIn(st, p.name) : edgesOut(st, p.name)).map((e) => {
+    const end = dir === "in" ? e.from : e.to;
+    return `${nameOf(end.node)} · ${end.pill}`;
+  });
+  const rows: [string, string][] = [
+    [tp("Value"), valueAt(st, p.cell)],
+    [tp("Unit"), p.unit ?? ""],
+    [
+      tp(dir === "in" ? "From" : "To"),
+      links.length ? links.join(", ") : tp(dir === "in" ? "NoFrom" : "NoTo"),
+    ],
+  ];
+  box.hidden = false;
+  box.replaceChildren(
+    el("strong", { text: `${tp(dir === "in" ? "In" : "Out")} · ${p.name} (${p.cell})` }),
+    ...rows.map(([k, v]) =>
+      el("div", {
+        className: "m01-slpanel-infoline",
+        children: [el("span", { className: "m01-slpanel-note", text: k }), v],
+      }),
+    ),
+    createButton({
+      label: tp("Close"),
+      variant: "ghost",
+      size: "sm",
+      onClick: () => ((st.info = null), drawPills(st)),
+    }),
+  );
+}
+
+/* ------------------------------ 편집기 ------------------------------ */
+
+/** 틀 수식을 고른 칸에 넣음 — 수식 입력줄에 쳐서 확정하는 길(되돌리기 · 검사 그대로) */
+function putFormula(st: State, formula: string): void {
+  const root = st.parts.sheet;
+  const bar = root.querySelector<HTMLTextAreaElement>(".ss-formula");
+  const addr = root.querySelector<HTMLInputElement>(".ss-addr");
+  if (!bar || !addr || st.readOnly) return;
+  const at = st.cell;
+  bar.focus();
+  bar.value = formula;
+  bar.dispatchEvent(new Event("input", { bubbles: true }));
+  bar.dispatchEvent(
+    new KeyboardEvent("keydown", { key: "Enter", ctrlKey: true, bubbles: true, cancelable: true }),
+  );
+  addr.value = at;
+  addr.dispatchEvent(
+    new KeyboardEvent("keydown", { key: "Enter", bubbles: true, cancelable: true }),
+  );
+}
+
+/** 편집기가 문서를 냄 — 선 받는 칸을 직접 고쳤으면 먼저 물음 */
+async function onBook(st: State, book: Workbook): Promise<void> {
+  if (st.busy) return;
+  const prev = st.sl;
+  const node = nodeOf(st);
+  const next: SheetLogic = { ...prev, workbook: { ...book, 활성: prev.workbook.활성 } };
+  const before = prev.workbook.시트.find((s) => s.id === node?.sheetId);
+  const after = book.시트.find((s) => s.id === node?.sheetId);
+  const hit = [...lockedCells(st)].find(
+    ([addr]) => JSON.stringify(before?.칸[addr]) !== JSON.stringify(after?.칸[addr]),
+  );
+  if (!hit) {
+    st.json = norm(book);
+    st.sl = next;
+    st.on.change(next);
+    return void setTimeout(() => refreshSnap(st), 0);
+  }
+  st.busy = true;
+  const ok = await showConfirmDialog(tp("BreakAsk"), tp("BreakOk"));
+  st.busy = false;
+  if (!ok) {
+    st.json = norm(shown(st));
+    return st.handle?.setDoc(structuredClone(shown(st)));
+  }
+  try {
+    const cut = disconnect(next, hit[1].id);
+    const sheet = cut.workbook.시트.find((s) => s.id === node?.sheetId);
+    const mine = after?.칸[hit[0]];
+    if (sheet) {
+      if (mine) sheet.칸[hit[0]] = mine;
+      else delete sheet.칸[hit[0]];
+    }
+    st.json = norm(cut.workbook);
+    st.sl = cut;
+    st.on.change(cut);
+    setTimeout(() => refreshSnap(st), 0);
+  } catch {
+    showToast(tp("Cannot"), "error");
+    st.handle?.setDoc(structuredClone(shown(st)));
+  }
+}
+
+async function mountSheet(st: State): Promise<void> {
+  const { createSpreadsheet } = await loadSheet();
+  if (!st.parts.sheet.isConnected || st.handle) return;
+  st.parts.sheet.replaceChildren();
+  const book = structuredClone(shown(st)); // 편집기가 제자리에서 고치므로 사본을 줌
+  st.json = norm(book);
+  st.handle = createSpreadsheet(st.parts.sheet, book, {
+    preview: true,
+    tabs: false,
+    readOnly: st.readOnly,
+    onChange: (b) => void onBook(st, b),
+    onSelect: (s) => {
+      st.cell = s.칸;
+      st.parts.cell.textContent = `${tp("Cell")} ${st.cell}`;
+      if (st.asking) drawBar(st);
+    },
+  });
+  st.observer = new MutationObserver(() => requestAnimationFrame(() => applyMarks(st)));
+  st.observer.observe(st.parts.sheet, {
+    childList: true,
+    subtree: true,
+    attributes: true,
+    attributeFilter: ["data-addr"],
+  });
+  refreshSnap(st);
+}
+
+/** 아래 시트 판 그리기 — 같은 상자면 편집기를 그대로 두고 알약 · 표시만 다시 */
+export function renderPanel(
+  host: HTMLElement,
+  sl: SheetLogic,
+  nodeId: string,
+  on: Handlers,
+  opts: { readOnly?: boolean } = {},
+): void {
+  const old = states.get(host);
+  const readOnly = !!opts.readOnly;
+  if (old && old.nodeId === nodeId && old.readOnly === readOnly) {
+    old.sl = sl;
+    old.on = on;
+    if (old.handle && norm(shown(old)) !== old.json) {
+      old.json = norm(shown(old));
+      old.handle.setDoc(structuredClone(shown(old)));
+      setTimeout(() => refreshSnap(old), 0);
+      return;
+    }
+    return old.redraw();
+  }
+  if (old) {
+    old.observer?.disconnect();
+    old.handle?.destroy();
+  }
+  const parts: State["parts"] = {
+    cell: el("span", { className: "m01-slpanel-cell", text: `${tp("Cell")} A1` }),
+    bar: el("div", { className: "m01-slpanel-bar" }),
+    msg: el("p", { className: "m01-slpanel-msg", attrs: { role: "status" } }),
+    sheet: el("div", { className: "m01-slpanel-sheet", text: tp("Loading") }),
+    pills: el("div", { className: "m01-slpanel-pills" }),
+    info: el("div", { className: "m01-slpanel-info" }),
+  };
+  const st: State = {
+    nodeId,
+    sl,
+    on,
+    readOnly,
+    handle: null,
+    snap: {},
+    json: "",
+    cell: "A1",
+    info: null,
+    asking: null,
+    busy: false,
+    parts,
+    observer: null,
+    redraw: () => {
+      drawBar(st);
+      drawPills(st);
+      applyMarks(st);
+    },
+  };
+  states.set(host, st);
+  const node = nodeOf(st);
+  host.classList.add("m01-slpanel");
+  host.replaceChildren(
+    el("div", {
+      className: "m01-slpanel-head",
+      children: [el("strong", { text: node?.name ?? "" }), parts.cell],
+    }),
+    parts.bar,
+    parts.msg,
+    parts.sheet,
+    parts.pills,
+    parts.info,
+  );
+  parts.msg.hidden = true;
+  st.redraw();
+  void mountSheet(st);
+}