diff --git a/packages/admin/src/components/app.css b/packages/admin/src/components/app.css
index b29a6c7dd9..0290c5817b 100644
--- a/packages/admin/src/components/app.css
+++ b/packages/admin/src/components/app.css
@@ -176,7 +176,11 @@ body {
     font: inherit;
 }
 
-.admin-actions button {
+/* 「← 一覧に戻る」など詳細画面の戻るボタンもアクションボタンと同一ルールに
+   統合して見た目を完全一致させる（font を指定すると UA 既定より大きくなり
+   一回り大きく見えたため、両者で font 未指定=UA 既定に揃える）。 */
+.admin-actions button,
+.admin-back-button {
     padding: 0.4rem 0.9rem;
     border: 1px solid hsl(220, 15%, 75%);
     border-radius: 0.4rem;
@@ -184,6 +188,14 @@ body {
     cursor: pointer;
 }
 
+.admin-back-button {
+    margin-bottom: 1rem;
+}
+
+.admin-back-button:hover {
+    background: hsl(220, 15%, 96%);
+}
+
 .admin-confirm {
     display: inline-flex;
     align-items: center;
diff --git a/packages/admin/src/components/bug-reports-view.jsx b/packages/admin/src/components/bug-reports-view.jsx
index bf2b1a4c6d..d077f8fc08 100644
--- a/packages/admin/src/components/bug-reports-view.jsx
+++ b/packages/admin/src/components/bug-reports-view.jsx
@@ -116,6 +116,7 @@ const BugReportDetail = ({reportId, stage, onBack, onChanged}) => {
     return (
         <div data-testid="bug-admin-detail">
             <button
+                className="admin-back-button"
                 data-testid="bug-admin-back"
                 type="button"
                 onClick={onBack}
diff --git a/packages/admin/src/components/classrooms-view.jsx b/packages/admin/src/components/classrooms-view.jsx
index 50c2cee64f..694576e926 100644
--- a/packages/admin/src/components/classrooms-view.jsx
+++ b/packages/admin/src/components/classrooms-view.jsx
@@ -211,6 +211,7 @@ const ClassroomDetail = ({classroomId, onBack, onChanged}) => {
     return (
         <div data-testid="classroom-admin-detail">
             <button
+                className="admin-back-button"
                 data-testid="classroom-admin-back"
                 type="button"
                 onClick={onBack}
@@ -360,6 +361,7 @@ const RestorePanel = ({classroomId, onBack}) => {
                     </p>
                 )}
                 <button
+                    className="admin-back-button"
                     data-testid="restore-admin-done-back"
                     type="button"
                     onClick={onBack}
@@ -373,6 +375,7 @@ const RestorePanel = ({classroomId, onBack}) => {
             <div data-testid="restore-admin-alive">
                 <p>{'このクラスはまだ存在しています。アーカイブからの復旧は先生自身のクラス管理画面から行えます。'}</p>
                 <button
+                    className="admin-back-button"
                     data-testid="restore-admin-back"
                     type="button"
                     onClick={onBack}
@@ -384,6 +387,7 @@ const RestorePanel = ({classroomId, onBack}) => {
     return (
         <div data-testid="restore-admin-plan">
             <button
+                className="admin-back-button"
                 data-testid="restore-admin-back"
                 type="button"
                 onClick={onBack}
diff --git a/packages/admin/src/components/shared-assignments-view.jsx b/packages/admin/src/components/shared-assignments-view.jsx
index d933fb1ece..8497bd5ed6 100644
--- a/packages/admin/src/components/shared-assignments-view.jsx
+++ b/packages/admin/src/components/shared-assignments-view.jsx
@@ -13,6 +13,15 @@ import {
     setSharedStatus
 } from '../lib/admin-api.js';
 
+// 限定公開は属性・著者名・教科などを省略できる（#1109）。データ欠損では
+// なく「先生が未入力」なので、運営が見て意味がわかるよう undefined を
+// そのまま出さず「未指定」と明示する。
+const UNSPECIFIED = '未指定';
+const orUnspecified = value => {
+    if (typeof value === 'undefined' || value === null || value === '') return UNSPECIFIED;
+    return value;
+};
+
 const StatusBadge = ({status}) => (
     <span className={`admin-badge ${status === 'published' ? 'admin-badge-ok' : 'admin-badge-muted'}`}>
         {status === 'published' ? '公開中' : '非公開'}
@@ -117,6 +126,7 @@ const SharedDetail = ({sharedId, onBack, onChanged}) => {
     return (
         <div data-testid="shared-admin-detail">
             <button
+                className="admin-back-button"
                 data-testid="shared-admin-back"
                 type="button"
                 onClick={onBack}
@@ -134,11 +144,13 @@ const SharedDetail = ({sharedId, onBack, onChanged}) => {
                 className="admin-meta"
                 data-testid="shared-admin-credit"
             >
-                {`© ${detail.authorName}${detail.authorAffiliation ? `（${detail.authorAffiliation}）` : ''} / CC BY 4.0`}
-                {` ・ 取り込み ${detail.reuseCount} 回`}
+                {`© ${orUnspecified(detail.authorName)}`}
+                {detail.authorAffiliation ? `（${detail.authorAffiliation}）` : ''}
+                {` / CC BY 4.0 ・ 取り込み ${detail.reuseCount} 回`}
             </p>
             <p className="admin-meta">
-                {`${detail.schoolLevel} / ${detail.subject} / タグ: ${(detail.tags || []).join(', ') || '-'}`}
+                {`${orUnspecified(detail.schoolLevel)} / ${orUnspecified(detail.subject)}`}
+                {` / タグ: ${(detail.tags || []).join(', ') || UNSPECIFIED}`}
             </p>
             {detail.supplementUrl ? (
                 <p
@@ -388,7 +400,8 @@ const SharedAssignmentsView = () => {
                                 <VisibilityBadge visibility={item.visibility} />
                                 <RecommendedBadge recommended={item.recommended} />
                                 <span className="admin-meta">
-                                    {`${item.authorName} ・ 取り込み ${item.reuseCount} 回 ・ ${item.createdAt}`}
+                                    {`${orUnspecified(item.authorName)} ・ 取り込み ${item.reuseCount} 回`}
+                                    {` ・ ${item.createdAt}`}
                                 </span>
                             </button>
                         </li>
diff --git a/packages/admin/test/unit/shared-assignments-view.test.jsx b/packages/admin/test/unit/shared-assignments-view.test.jsx
index 0bb892bf0f..ffcdc1511d 100644
--- a/packages/admin/test/unit/shared-assignments-view.test.jsx
+++ b/packages/admin/test/unit/shared-assignments-view.test.jsx
@@ -148,4 +148,27 @@ describe('SharedAssignmentsView (issue #1083)', () => {
         expect(mockSetStatus).not.toHaveBeenCalled();
         expect(screen.queryByTestId('shared-admin-confirm')).not.toBeInTheDocument();
     });
+
+    test('限定公開で未入力の属性は undefined でなく「未指定」と表示する (レビュー指摘)', async () => {
+        // 限定公開は authorName / schoolLevel / subject 等を省略できる
+        // （キーそのものが無い＝undefined になる）。
+        mockFetchDetail.mockResolvedValue({
+            sharedId: 's1',
+            title: 'smoke限定公開',
+            status: 'published',
+            visibility: 'limited',
+            tags: [],
+            reuseCount: 0,
+            pages: [{text: 'ページ1', imageUrl: null}],
+            starterUrl: null
+        });
+        render(<SharedAssignmentsView />);
+        await waitFor(() => screen.getByTestId('shared-admin-queue-item-s1'));
+        fireEvent.click(screen.getByTestId('shared-admin-queue-item-s1'));
+        await waitFor(() => screen.getByTestId('shared-admin-detail'));
+
+        const detailEl = screen.getByTestId('shared-admin-detail');
+        expect(detailEl.textContent).not.toContain('undefined');
+        expect(screen.getByTestId('shared-admin-credit').textContent).toContain('未指定');
+    });
 });