Media queries containing '/' get minified wrong

[lukeapage]

See less/less.js#1349

the following css gets mangled when compressing with ycssmin

@media print,
       (-o-min-device-pixel-ratio: 5/4),
       (-webkit-min-device-pixel-ratio: 1.25),
       (min-resolution: 120dpi) {
    /* Style adjustments for high resolution devices */
    // a {
    //   font-size: 4rem;
    // }
}


/**===================================================**\
/**  PRINT STYLES
/**===================================================**/
@media only print {
  // *                             { background: @trans !important; box-shadow: none !important; color: @black !important; text-shadow: none !important; }
  a,
  a:visited                     { text-decoration: underline; }
  a[href]:after                 { content: " (" attr(href) ")"; }
  abbr[title]:after             { content: " (" attr(title) ")"; }

  /** MANUALLY TRUNCATED FOR BREVITY **/
}