Except for the IE browser, other browsers cannot recognize the html writing method_html/css_WEB-ITnose

When I was writing an html page recently, I found that after the top border margin-top was positioned, IE was different from other browsers, so I used a writing method to distinguish IE from other browsers

<!--[if !IE]>    <div class="clear-30"></div>这样写是错误的    <![endif]-->

Writing like the above is wrong. The correct writing should be like this:

<!--[if !IE]><-->    <div class="clear-30"></div>这样写才是正确的    <![endif]-->

This function applies to the top navigation of www.weixh.net