I have wrote my own embed-server, which can generate response to web browsers. The generated "main page" is like the following html.
<!DOCTYPE html>
<html><head><link rel="stylesheet" href="styles.css"><title>ABC Inc. Web Configurator</title></head><body>
<nav><p>[<b>Home</b>]</p></nav>
<table>
<tr><td><a href=Config>Config</a></td></tr>
<tr><td><a href=Logger>Logger</a></td></tr>
</table>
<footer>Web Configurator © ABC Inc. 2014 - 2015</footer></body></html>And the generated CSS file is
.even{
 background-color: #EFF;
}
.odd{
 background-color: #FFE;
}
.title{
 background-color: #226;
 color: #EEF;
}
a{
 color: #36C;
 text-decoration: none;
}
a:hover{
 text-decoration: underline;
}
body{
 font-family: Tahoma;
 font-size: 100%;
}
footer{
 color: #999;
 font-size: 0.7rem;
}
nav{
 background-color: #DDF;
 font-size: 1.1rem;
}
td{
 min-width: 60px;
}When I browse the main page by Chrome 43 or Firefox 39, they're both okay. However, when I use IE11, the CSS not apply to the html, even though that I can make sure IE11 have access the CSS file from my server. If I press F12 in IE, the DOM manager shows no stylesheet in this page.
BTW, my URL is http://localhost:8888/, and need a basic authentication. Any idea how can I fix it?
UPDATE
- I've read the stackoverflow thread before, and I'm sure my problem is not about browser caching. Thanks Mauro for notification. 
- I've tried Chrome + IE tab2, the CSS works, but not apply to nav and footer tag. I guess IE tab not support HTML5. 
UPDATE
- I've try both of closed and non-closed link tag, both of them are not solve my problem with IE11. 
- I've try to disable Basic Authentication, still not working. 
UPDATE
- The CSS also works in Firefox 39. 
- The CSS works with IE11 + Compatible mode (but HTML5 tags will be ignored). 
 
     
     
     
    