계정 추가 폼이 작은 박스 안에서도 버튼까지 다 보이도록 조정

박스 크기를 살짝 키우고(25% 크기 기준 +45%) 입력 필드를 촘촘하게
(isDense, 작은 폰트/패딩) 만들어 스크롤 없이 등록 버튼까지 모두
보이도록 함.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

lib/ui/teacher_student_management_page.dart

@@ -397,10 +397,12 @@ class _TeacherStudentManagementPageState
     );
   }
 
-  // 📝 [정사각형 박스 1] 신규 학생 계정 추가 폼.
+  // 📝 [정사각형 박스 1] 신규 학생 계정 추가 폼. 박스가 작아도 버튼까지 다 보이도록 촘촘하게 배치.
   Widget _buildAddAccountBox() {
+    const InputDecoration Function(String, IconData) fieldDecoration =
+        _compactFieldDecoration;
     return Container(
-      padding: const EdgeInsets.all(20),
+      padding: const EdgeInsets.all(10),
       decoration: BoxDecoration(
         color: Colors.white,
         borderRadius: BorderRadius.circular(24),
@@ -418,35 +420,27 @@ class _TeacherStudentManagementPageState
             TextField(
               controller: _addIdController,
               keyboardType: TextInputType.number,
-              decoration: const InputDecoration(
-                labelText: '학번',
-                prefixIcon: Icon(Icons.badge),
+              style: const TextStyle(fontSize: 12),
+              decoration: fieldDecoration('학번', Icons.badge),
             ),
-            ),
-            const SizedBox(height: 12),
+            const SizedBox(height: 4),
             TextField(
               controller: _addNameController,
-              decoration: const InputDecoration(
-                labelText: '이름',
-                prefixIcon: Icon(Icons.person),
+              style: const TextStyle(fontSize: 12),
+              decoration: fieldDecoration('이름', Icons.person),
             ),
-            ),
-            const SizedBox(height: 12),
+            const SizedBox(height: 4),
             TextField(
               controller: _addPwController,
               obscureText: true,
-              decoration: const InputDecoration(
-                labelText: '초기 비밀번호',
-                prefixIcon: Icon(Icons.lock),
+              style: const TextStyle(fontSize: 12),
+              decoration: fieldDecoration('초기 비밀번호', Icons.lock),
             ),
-            ),
-            const SizedBox(height: 12),
+            const SizedBox(height: 4),
             DropdownButtonFormField<int>(
               initialValue: _selectedGrade,
-              decoration: const InputDecoration(
-                labelText: '학년 (선택)',
-                prefixIcon: Icon(Icons.class_),
-              ),
+              style: const TextStyle(fontSize: 12, color: Colors.black87),
+              decoration: fieldDecoration('학년 (선택)', Icons.class_),
               items: const [
                 DropdownMenuItem(value: 1, child: Text('1학년')),
                 DropdownMenuItem(value: 2, child: Text('2학년')),
@@ -454,26 +448,34 @@ class _TeacherStudentManagementPageState
               ],
               onChanged: (value) => setState(() => _selectedGrade = value),
             ),
-            const SizedBox(height: 20),
+            const SizedBox(height: 6),
             SizedBox(
               width: double.infinity,
-              height: 50,
+              height: 30,
               child: ElevatedButton(
                 onPressed: _controller.isWorking ? null : _addStudentAccount,
                 style: ElevatedButton.styleFrom(
                   backgroundColor: Colors.orange,
                   foregroundColor: Colors.white,
+                  padding: EdgeInsets.zero,
                   shape: RoundedRectangleBorder(
-                    borderRadius: BorderRadius.circular(12),
+                    borderRadius: BorderRadius.circular(10),
                   ),
                 ),
                 child: _controller.isWorking
-                    ? const CircularProgressIndicator(color: Colors.white)
+                    ? const SizedBox(
+                        width: 16,
+                        height: 16,
+                        child: CircularProgressIndicator(
+                          color: Colors.white,
+                          strokeWidth: 2,
+                        ),
+                      )
                     : const Text(
                         '학생 등록 완료',
                         style: TextStyle(
                           fontWeight: FontWeight.bold,
-                          fontSize: 15,
+                          fontSize: 12,
                         ),
                       ),
               ),
@@ -484,6 +486,16 @@ class _TeacherStudentManagementPageState
     );
   }
 
+  static InputDecoration _compactFieldDecoration(String label, IconData icon) {
+    return InputDecoration(
+      labelText: label,
+      labelStyle: const TextStyle(fontSize: 12),
+      prefixIcon: Icon(icon, size: 16),
+      isDense: true,
+      contentPadding: const EdgeInsets.symmetric(vertical: 4, horizontal: 8),
+    );
+  }
+
   // 📤 [정사각형 박스 2] 엑셀 일괄 등록 드롭존.
   Widget _buildExcelBox() {
     return DropTarget(
@@ -673,9 +685,9 @@ class _TeacherStudentManagementPageState
                 // 📐 학생 목록 타일은 "실시간 출석 확인" 목록의 타일(220x148)과 동일하게 맞춘다.
                 final bool isWide = constraints.maxWidth >= 800;
                 final double listWidth = constraints.maxWidth;
-                // 📉 계정 추가 / 엑셀 등록 칸: 정사각형 기본 크기의 25%로 축소.
+                // 📉 계정 추가 / 엑셀 등록 칸: 정사각형 기본 크기의 25%(+ 버튼까지 다 보이도록 확대).
                 final double formSquareSize =
-                    ((constraints.maxWidth - 20) / 2) * 0.25;
+                    ((constraints.maxWidth - 20) / 2) * 0.25 * 1.45;
 
                 final Widget addBoxColumn = Column(
                   crossAxisAlignment: CrossAxisAlignment.start,