diff --git a/src/gui/panels/step7_inversion_panel.py b/src/gui/panels/step7_inversion_panel.py
index e92ff3a..56404a0 100644
--- a/src/gui/panels/step7_inversion_panel.py
+++ b/src/gui/panels/step7_inversion_panel.py
@@ -153,42 +153,56 @@ class Step7InversionPanel(QWidget):
         right_layout.setContentsMargins(0, 0, 0, 0)
         right_layout.setSpacing(8)
 
-        # 按钮工具栏
-        btn_layout = QHBoxLayout()
-        btn_layout.setContentsMargins(0, 0, 0, 0)
-        btn_layout.setSpacing(10)
+        # 按钮工具栏（拆分为两行，防止控件挤在一行撑宽面板）
+        btn_wrapper = QVBoxLayout()
+        btn_wrapper.setContentsMargins(0, 0, 0, 0)
+        btn_wrapper.setSpacing(5)
 
-        btn_layout.addWidget(QLabel("按类别筛选:"))
+        # 第1行：[按类别筛选:] [下拉框] [全选] [清空]
+        row1 = QHBoxLayout()
+        row1.setContentsMargins(0, 0, 0, 0)
+        row1.setSpacing(10)
+
+        row1.addWidget(QLabel("按类别筛选:"))
         self.category_combo = QComboBox()
         self.category_combo.setStyleSheet("""
             QComboBox { padding: 4px 8px; border: 1px solid #C0C0C0; border-radius: 4px; min-height: 24px; }
         """)
         self.category_combo.currentIndexChanged.connect(self._on_category_changed)
-        btn_layout.addWidget(self.category_combo)
-        btn_layout.addSpacing(10)
+        row1.addWidget(self.category_combo)
+        row1.addSpacing(10)
 
         self.btn_select_all = QPushButton("全选")
         self.btn_select_none = QPushButton("清空")
+        for btn in [self.btn_select_all, self.btn_select_none]:
+            btn.setStyleSheet(ModernStylesheet.get_button_stylesheet('normal'))
+            btn.setFixedHeight(30)
+            row1.addWidget(btn)
+        row1.addStretch()
+
+        # 第2行：[仅比值型] [仅浓度型] [重新加载库] [已选: N]
+        row2 = QHBoxLayout()
+        row2.setContentsMargins(0, 0, 0, 0)
+        row2.setSpacing(10)
+
         self.btn_select_ratio = QPushButton("仅比值型")
         self.btn_select_conc = QPushButton("仅浓度型")
         self.btn_reload = QPushButton("重新加载库")
-
-        for btn in [self.btn_select_all, self.btn_select_none,
-                    self.btn_select_ratio, self.btn_select_conc, self.btn_reload]:
-            base_style = ModernStylesheet.get_button_stylesheet('normal')
-            btn.setStyleSheet(base_style + "\nQPushButton { padding-left: 14px; padding-right: 14px; }")
+        for btn in [self.btn_select_ratio, self.btn_select_conc, self.btn_reload]:
+            btn.setStyleSheet(ModernStylesheet.get_button_stylesheet('normal') +
+                              "\nQPushButton { padding-left: 14px; padding-right: 14px; }")
             btn.setFixedHeight(30)
-            btn.setSizePolicy(QSizePolicy.Minimum, QSizePolicy.Fixed)
-            btn_layout.addWidget(btn)
-
-        btn_layout.addStretch()
+            row2.addWidget(btn)
 
         self.formula_count_label = QLabel("已选: 0 | 显示: 0 / 共 0 个")
         self.formula_count_label.setStyleSheet(
             "color: #666666; font-size: 13px; font-weight: bold; padding-right: 10px;")
-        btn_layout.addWidget(self.formula_count_label)
+        row2.addWidget(self.formula_count_label)
+        row2.addStretch()
 
-        right_layout.addLayout(btn_layout)
+        btn_wrapper.addLayout(row1)
+        btn_wrapper.addLayout(row2)
+        right_layout.addLayout(btn_wrapper)
 
         # 列表框
         self.formula_list = NoScrollPassListWidget()