doc: 移除主题菜单

Author: ArgoZhang

src/BootstrapBlazor.Server/Components/Components/Header.razor

@@ -20,12 +20,12 @@
             <li class="nav-item">
                 <a class="nav-link" href="tutorials">@TutorialsText</a>
             </li>
-            @if (CultureInfo.CurrentUICulture.Name == "zh-CN")
+            @* @if (CultureInfo.CurrentUICulture.Name == "zh-CN")
             {
                 <li class="nav-item">
                     <a class="nav-link" href="https://theme.blazor.zone">主题</a>
                 </li>
-            }
+            } *@
         </ul>
     </div>
     <div class="d-flex flex-fill"></div>