diff --git a/B06_Section/B06_Section_UI_Page.ts b/B06_Section/B06_Section_UI_Page.ts
index 3f2f28b7..0a3f68db 100644
--- a/B06_Section/B06_Section_UI_Page.ts
+++ b/B06_Section/B06_Section_UI_Page.ts
@@ -1,13 +1,10 @@
 import { writeCrossDesignChoice } from "./B06_Section_Cross_Design_Session";
 import { CURRENT_PROJECT_ID_KEY, ROUTES } from "@config/config_frontend";
 import { leaveForDashboard } from "../A00_Common/b_missing_data_guard";
-import { stateKey } from "../A00_Common/b_page_state";
+import { stateKey, storageOf } from "../A00_Common/b_page_state";
 import { navigateTo } from "../A00_Common/router";
 import { createButton, createInputField, showToast } from "@ui/ui_template_elements";
-import type {
-  StructureInstance,
-  StructureType,
-} from "../B05_Profile/B05_Profile_Api_Structures";
+import type { StructureInstance, StructureType } from "../B05_Profile/B05_Profile_Api_Structures";
 import { createWorkflowLayout } from "@ui/ui_template_workflow_layout";
 import { attachCollapsible } from "@ui/ui_template_collapsible";
 import { workflowSteps } from "../A00_Common/b_page_scaffold";
@@ -144,8 +141,7 @@ export async function renderB06ProfileCross(root: HTMLElement): Promise<void> {
   // 「구조물 배치」 — B05와 같은 컨테이너·하단 목록 템플릿(2026-08-29 일원화).
   // 하단 고정 dock 도 B05와 같은 구조: [구조물 목록][구분선][액션 버튼 행].
   let structureMarksSink:
-    | ((structures: StructureInstance[], types: StructureType[]) => void)
-    | null = null;
+    ((structures: StructureInstance[], types: StructureType[]) => void) | null = null;
   const structuresPanel = createB06StructuresPanel({
     projectId,
     // 횡단도·3D 넘김값에서 고른 것이 폼에 실릴 때 좌측 패널을 펼친다(2026-09-04 사용자).
@@ -533,7 +529,7 @@ export async function renderB06ProfileCross(root: HTMLElement): Promise<void> {
     const width = crossHalfWidth();
     if (!key || width === undefined) return;
     try {
-      window.sessionStorage.setItem(key, String(width));
+      storageOf(key).setItem(key, String(width));
     } catch {
       /* 무시 */
     }
@@ -712,7 +708,7 @@ export async function renderB06ProfileCross(root: HTMLElement): Promise<void> {
     // 세션에 보관된 표시 반폭이 있으면 그것이 우선한다(사용자가 마지막으로 지정한 값).
     const sessionDisplayKey = displaySessionKey();
     if (sessionDisplayKey) {
-      const sessionDisplay = Number(window.sessionStorage.getItem(sessionDisplayKey));
+      const sessionDisplay = Number(storageOf(sessionDisplayKey).getItem(sessionDisplayKey));
       if (Number.isFinite(sessionDisplay) && sessionDisplay > 0)
         crossHalfWidthField.input.value = sessionDisplay.toFixed(1);
     }
diff --git a/B06_Section/B06_Section_UI_Page_Persist.ts b/B06_Section/B06_Section_UI_Page_Persist.ts
index 5c90c6fa..ba03afb1 100644
--- a/B06_Section/B06_Section_UI_Page_Persist.ts
+++ b/B06_Section/B06_Section_UI_Page_Persist.ts
@@ -21,7 +21,7 @@ import { flushPendingPipes } from "../B05_Profile/B05_Profile_Api_Pipes_Draft";
 import { flushPendingStructures } from "../B05_Profile/B05_Profile_Api_Structures";
 import { flushUphillOverrides } from "../B05_Profile/B05_Profile_Api_Fetch";
 import { buildCrossPatches, type CrossPatchSources } from "./B06_Section_UI_Page_Patches";
-import { readState } from "../A00_Common/b_page_state";
+import { readState, storageOf } from "../A00_Common/b_page_state";
 import {
   applyStructureAreaRows,
   STRUCTURE_AREA_KEYS,
@@ -92,7 +92,7 @@ export function createRockBoundaryStore(options: {
     const storageKey = sessionKey();
     if (!storageKey) return;
     try {
-      window.sessionStorage.setItem(storageKey, JSON.stringify(Object.fromEntries(offsets)));
+      storageOf(storageKey).setItem(storageKey, JSON.stringify(Object.fromEntries(offsets)));
     } catch {
       /* 세션 저장 실패는 무시(용량 초과 등) — 값은 메모리에 유지된다. */
     }
@@ -105,7 +105,7 @@ export function createRockBoundaryStore(options: {
       const storageKey = sessionKey();
       if (!storageKey) return;
       try {
-        const raw = window.sessionStorage.getItem(storageKey);
+        const raw = storageOf(storageKey).getItem(storageKey);
         if (!raw) return;
         const parsed = JSON.parse(raw) as Record<string, number>;
         Object.entries(parsed).forEach(([chainage, offset]) => {