disable unfinished link in top nav

site/templates/layout.html

@@ -45,16 +45,13 @@
           <a href="/components">组件</a>
         </li>
         <li class="{%- if post.filename === 'design' %}current{%- endif %}">
-          <a href="/docs/design">设计</a>
+          <a class="disabled" href="/docs/design">设计</a>
         </li>
         <li class="{%- if post.filename === 'modes' %}current{%- endif %}">
-          <a href="/docs/modes">模式</a>
+          <a class="disabled" href="/docs/modes">模式</a>
         </li>
         <li class="{%- if post.filename === 'cases' %}current{%- endif %}">
-          <a href="/docs/cases">案例</a>
-        </li>
-        <li class="{%- if post.filename === 'download' %}current{%- endif %}">
-          <a href="/docs/download">下载</a>
+          <a class="disabled" href="/docs/cases">案例</a>
         </li>
       </ul>
     </nav>

static/style.css

@@ -247,6 +247,12 @@ a.logo {
   display: block;
 }
 
+.nav ul li a.disabled {
+  cursor: not-allowed;
+  color: #ddd !important;
+  pointer-events: none;
+}
+
 .nav ul li.current a {
   color: #71B5DE;
   font-weight: bold;