fix: 修复中国地图页面搜索栏不显示的问题

- 简化header布局结构，移除flex-col导致的布局问题
- 使用统一的水平flex布局：左侧(返回/Logo)、中间(搜索)、右侧(区域)
- 改用 style.display 直接控制显示隐藏，更可靠
- 优化响应式布局，确保PC端搜索框正常显示

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

index.html

@@ -744,10 +744,11 @@
 
         <!-- 地图界面 -->
         <div id="map-interface">
-            <header class="glass-header fixed top-0 w-full h-16 flex flex-col md:flex-row items-center justify-between px-4 md:px-8 z-50">
+            <header class="glass-header fixed top-0 w-full h-16 flex items-center justify-between px-4 md:px-8 z-50">
-                <div class="flex items-center justify-between w-full md:w-auto">
+                <!-- 左侧：返回按钮或Logo -->
+                <div class="flex items-center gap-4 flex-shrink-0">
                     <!-- 返回按钮（省级地图显示） -->
-                    <button id="map-back-btn" class="hidden flex items-center gap-1 md:gap-2 text-gray-400 hover:text-white transition flex-shrink-0" onclick="window.resetMapToChina()">
+                    <button id="map-back-btn" class="hidden items-center gap-1 md:gap-2 text-gray-400 hover:text-white transition" onclick="window.resetMapToChina()">
                         <svg class="w-4 h-4 md:w-5 md:h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                             <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M10 19l-7-7m0 0l7-7m-7 7h18"></path>
                         </svg>
@@ -755,7 +756,7 @@
                     </button>
                     
                     <!-- Logo区域 -->
-                    <div id="map-logo-area" class="flex items-center gap-2 cursor-pointer flex-shrink-0">
+                    <div id="map-logo-area" class="flex items-center gap-2 cursor-pointer">
                         <img src="https://ddcz-1315997005.cos.ap-nanjing.myqcloud.com/static/img/duoduo_logo/LOGO_1097x300.png"
                              alt="多多畅职" class="h-6 md:h-8 w-auto object-contain">
                         <div class="text-white font-bold text-xs md:text-sm tracking-wide hidden sm:block">多多畅职企业内推平台</div>
@@ -763,12 +764,12 @@
                     </div>
                 </div>
                 
-                <!-- 搜索框（PC端） -->
+                <!-- 中间：搜索框（PC端） -->
                 <div class="relative w-1/3 hidden md:block">
                     <input type="text" id="search-input" placeholder="搜索省份、城市、企业..." class="search-input w-full py-2 px-5 rounded-full text-center text-sm placeholder-gray-400">
                 </div>
                 
-                <!-- 当前区域显示 -->
+                <!-- 右侧：当前区域显示 -->
                 <div class="flex items-center gap-2 text-white text-xs md:text-sm flex-shrink-0">
                     <span class="text-gray-400 hidden sm:inline">当前区域:</span>
                     <span id="top-region-name" class="text-cyan-300 font-bold">全国</span>

js/ui/MapInterface.js

@@ -93,12 +93,11 @@ export class MapInterface {
             document.getElementById('breadcrumb-container').classList.add('hidden');
             const backBtn = document.getElementById('map-back-btn');
             if (backBtn) {
-                backBtn.classList.add('hidden');
+                backBtn.style.display = 'none';
-                backBtn.classList.remove('flex');
             }
             const logoArea = document.getElementById('map-logo-area');
             if (logoArea) {
-                logoArea.classList.remove('hidden');
+                logoArea.style.display = 'flex';
             }
             
             document.getElementById('top-region-name').innerText = '全国';
@@ -124,12 +123,11 @@ export class MapInterface {
                 // 显示返回按钮，隐藏logo
                 const backBtn = document.getElementById('map-back-btn');
                 if (backBtn) {
-                    backBtn.classList.remove('hidden');
+                    backBtn.style.display = 'flex';
-                    backBtn.classList.add('flex');
                 }
                 const logoArea = document.getElementById('map-logo-area');
                 if (logoArea) {
-                    logoArea.classList.add('hidden');
+                    logoArea.style.display = 'none';
                 }
                 
                 document.getElementById('top-region-name').innerText = provinceInfo.name;