diff --git a/src/components/Sidebar.tsx b/src/components/Sidebar.tsx
index c9fd43f..3f5a713 100644
--- a/src/components/Sidebar.tsx
+++ b/src/components/Sidebar.tsx
@@ -30,7 +30,7 @@ const SidebarContent: Component<SidebarContentProps> = (props) => {
 
   return (
     <div class="flex flex-col h-full">
-      <div class="p-4 border-b">
+      <div class="p-4 border-b border-b-gray-200">
         <div class="flex items-center justify-between">
           <h2 class="text-lg font-bold text-gray-900">目录</h2>
           <Show when={!props.isDesktop}>
@@ -63,7 +63,7 @@ const SidebarContent: Component<SidebarContentProps> = (props) => {
 
       {/* 当前文件标题滚动区域 */}
       <Show when={currentFileHeadings().length > 0}>
-        <div class="flex-1 border-t overflow-y-auto p-4 min-h-0">
+        <div class="flex-1 border-t-gray-200 border-t overflow-y-auto p-4 min-h-0">
           <h3 class="text-xs font-semibold text-gray-500 uppercase mb-2 px-2">
             本页
           </h3>