( function ( window, doc, undef ) {
  // Takes a preloaded css obj (changes in different browsers) and injects it into the head
  yepnope.injectCss = function( href, cb, attrs, timeout, /* Internal use */ err, internal ) {

    // Create stylesheet link
    var link = document.createElement( "link" ),
        onload = function() {
          if ( ! done ) {
            done = 1;
            link.removeAttribute("id");
            setTimeout( cb, 0 );
          }
        },
        id = "yn" + new Date,
        ref, done, i;

    cb = internal ? yepnope.executeStack : ( cb || function(){} );
    timeout = timeout || yepnope.errorTimeout;
    // Add attributes
    link.href = href;
    link.rel  = "stylesheet";
    link.type = "text/css";
    link.id = id;

    // Add our extra attributes to the link element
    for ( i in attrs ) {
      link.setAttribute( i, attrs[ i ] );
    }


    if ( ! err ) {
      ref = document.getElementsByTagName('base')[0] || document.getElementsByTagName('script')[0];
      ref.parentNode.insertBefore( link, ref );
      link.onload = onload;

      function poll() {
        try {
            var sheets = document.styleSheets;
            for(var j=0, k=sheets.length; j<k; j++) {
                if(sheets[j].ownerNode.id == id) {
                    // this throws an exception, I believe, if not full loaded (was originally just "sheets[j].cssRules;")
                    if (sheets[j].cssRules.length)
                        return onload();
                }
            }
            // if we get here, its not in document.styleSheets (we never saw the ID)
            throw new Error;
        } catch(e) {
            // Keep polling
            setTimeout(poll, 20);
        }
      }
      poll();
    }
  }
})( this, this.document );

( function ( window, doc, undef ) {
  // Takes a preloaded css obj (changes in different browsers) and injects it into the head
  yepnope.injectCss = function( href, cb, attrs, timeout, /* Internal use */ err, internal ) {

    // Create stylesheet link
    var link = document.createElement( "link" ),
        onload = function() {
          if ( ! done ) {
            done = 1;
            link.removeAttribute("id");
            setTimeout( cb, 0 );
          }
        },
        id = "yn" + +new Date,
        ref, done, i;

    cb = internal ? yepnope.executeStack : ( cb || function(){} );
    timeout = timeout || yepnope.errorTimeout;
    // Add attributes
    link.href = href;
    link.rel  = "stylesheet";
    link.type = "text/css";
    link.id = id;

    // Add our extra attributes to the link element
    for ( i in attrs ) {
      link.setAttribute( i, attrs[ i ] );
    }


    if ( ! err ) {
      ref = document.getElementsByTagName('base')[0] || document.getElementsByTagName('script')[0];
      ref.parentNode.insertBefore( link, ref );
      link.onload = onload;

      function poll() {
        try {
            var sheets = document.styleSheets;
            for(var j=0, k=sheets.length; j<k; j++) {
                if(sheets[j].ownerNode.id == id) {
                    // this throws an exception, I believe, if not full loaded (was originally just "sheets[j].cssRules;")
                    if (sheets[j].cssRules.length)
                        return onload();
                }
            }
            // if we get here, its not in document.styleSheets (we never saw the ID)
            throw new Error;
        } catch(e) {
            // Keep polling
            setTimeout(poll, 20);
        }
      }
      poll();
    }
  }
})( this, this.document );

use number instead of string for time based ID of injected link elemented