Update index.html

语义修复

index.html

@@ -98,7 +98,7 @@
                     <div id="download">
                         <a id="download_url" href="http://my-card.in/mycard/download" class="download_active">立即下载</a>
                         <a class="download_information">最新版本: <span id="download_version">Loading...</span></a>
-                        <p class="platform">支持的平台: <a href="http://my-card.in/mycard/download?platform=win32">Windows</a>, <a href="https://github.com/mycard/mycard/wiki/linux">Linux</a></p>
+                        <p id="platform">支持的平台: <a href="http://my-card.in/mycard/download?platform=win32">Windows</a>, <a href="https://github.com/mycard/mycard/wiki/linux">Linux</a></p>
                     </div>
                     <div id="download_sublist">
                         <a href="http://my-card.in/mycard/updates">更新补丁</a></br>
@@ -157,4 +157,4 @@
     </div>
 </footer>
 </body>
-</html>
\ No newline at end of file
+</html>