agent=navigator.userAgent;

    if(agent.search(/Opera/)!=-1)
     document.write("<link href=\"style_opera.css\" rel=\"stylesheet\" type=\"text\/css\" media=\"all\" \/>");
    else
     if(agent.search(/Netscape/)!=-1)
      document.write("<link href=\"style_netscape.css\" rel=\"stylesheet\" type=\"text\/css\" media=\"all\" \/>");
     else
      if(agent.search(/MSIE/)!=-1)
       document.write("<link href=\"style_msie.css\" rel=\"stylesheet\" type=\"text\/css\" media=\"all\" \/>");
      else
       if(agent.search(/Safari/)!=-1)
        document.write("<link href=\"style_safari.css\" rel=\"stylesheet\" type=\"text\/css\" media=\"all\" \/>");
      else
       document.write("<link href=\"style_default.css\" rel=\"stylesheet\" type=\"text\/css\" media=\"all\" \/>");