admin 렌더링 방식 변경

frontend/components/layout/MainHeader.tsx

@@ -1,6 +1,5 @@
 import { Logo } from "./Logo";
 import { SideMenu } from "./SideMenu";
-import { AdminButton } from "./AdminButton";
 import { UserDropdown } from "./UserDropdown";
 
 interface MainHeaderProps {
@@ -19,8 +18,8 @@ export function MainHeader({ user, onSidebarToggle, onProfileClick, onLogout }:
       <div className="flex h-full w-full items-center justify-between px-6">
         {/* Left side - Side Menu + Logo */}
         <div className="flex h-8 items-center gap-2">
-          {/* 햄버거 메뉴 버튼 - 모바일에서만 표시 */}
-          <div className="md:hidden">
+          {/* 햄버거 메뉴 버튼 - 1024px 미만에서 표시 */}
+          <div className="lg:hidden">
             <SideMenu onSidebarToggle={onSidebarToggle} />
           </div>
           <Logo />
@@ -28,7 +27,6 @@ export function MainHeader({ user, onSidebarToggle, onProfileClick, onLogout }:
 
         {/* Right side - Admin Button + User Menu */}
         <div className="flex h-8 items-center gap-2">
-          <AdminButton user={user} />
           <UserDropdown user={user} onProfileClick={onProfileClick} onLogout={onLogout} />
         </div>
       </div>