修正

frontend/opening_balance.html

@@ -39,10 +39,23 @@
 
     <br />
 
-    <button onclick="saveOpeningBalances()">保存</button>
     <button
-      onclick="location.href = 'trial-balance.html'"
-      class="back-button"
+      onclick="saveOpeningBalances()"
+      style="
+        margin: 0 10px 0 0;
+        padding: 8px 16px;
+        background: #28a745;
+        color: white;
+        border: none;
+        border-radius: 4px;
+        cursor: pointer;
+        font-size: 14px;
+      "
+    >
+      保存
+    </button>
+    <button
+      onclick="location.href = 'index.html'"
       style="
         margin: 0 0 20px 0;
         padding: 8px 16px;
@@ -54,7 +67,7 @@
         font-size: 14px;
       "
     >
-      ← 試算表に戻る
+      ← メインメニューに戻る
     </button>
 
     <script src="js/api.js"></script>