CodePen

HTML

            
              <h1>I'll be blue in IE 10 and black in everything else.</h1>
            
          
!

CSS

            
              html[data-useragent*='MSIE 10.0'] h1 {
  color: blue;
}

h1 {
  text-align: center;
  padding: 20px;
}
            
          
!

JavaScript

            
              var b = document.documentElement;
b.setAttribute('data-useragent',  navigator.userAgent);
b.setAttribute('data-platform', navigator.platform );

// IE 10 == Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Trident/6.0)
            
          
!
999px
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