CSDN(当前页面中树右边的拖动条是怎么实现的?急!!!

这是CSDN 首页代码 看看不行吗？
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<HTML>
<HEAD>
  <META NAME="Robots" CONTENT="noindex">
  <META content="text/html;charset=gb2312" http-equiv="Content-Type">
  <TITLE>欢迎来到CSDN新版论坛</TITLE>
  <script src="/Expert/style/get_css.js"></script>
  <SCRIPT LANGUAGE="JavaScript">
  // this page should never load inside of another frame
  if (top.location != self.location)
    {
    top.location = self.location;
    }  function InitSync()
  {
      if( "object" == typeof( top.deeptree ) && "unknown" == typeof( top.deeptree.Sync ) )
      {
        top.deeptree.Sync();
      }
  }
  </SCRIPT>
</HEAD><FRAMESET onload="InitSync();" rows="81,*" border="1" FRAMESPACING="0" TOPMARGIN="0" LEFTMARGIN="0" MARGINHEIGHT="0" MARGINWIDTH="0">
  <FRAME name="fraToolbar" src="/Top_Expert_Forum.htm?csdnstyle=" scrolling="no" border="0" frameborder="no" noresize TOPMARGIN="0" LEFTMARGIN="0" MARGINHEIGHT="0" MARGINWIDTH="0" ></FRAME>

    <FRAMESET name="fstMain" cols="216,*" border="10" frameborder="1" FRAMESPACING="10"  TOPMARGIN="0"  LEFTMARGIN="0" MARGINHEIGHT="0" MARGINWIDTH="0" >
      <FRAME name="fraLeftFrame" src="/expert/Deeptree/leftframe.asp?url=/expert/deeptree/welcome.asp?1=1&frame=&xmlsrc=/Expert/deeptree/Rooms/List.xml&csdnstyle=&myie=ie" TOPMARGIN="0" LEFTMARGIN="0" MARGINHEIGHT="0" MARGINWIDTH="0" FRAMEBORDER="1" BORDER="1"></FRAME>
      <FRAME name="fraRightFrame" src="/Expert/deeptree/rightframe.asp?url=/expert/deeptree/welcome.asp?1=1&typenum=1&xmlsrc=/Expert/deeptree/Rooms/List.xml&csdnstyle=&hidetoc=false&whichpage=&myie=ie" FRAMEBORDER="no" bordercolor="#000000"></FRAME>    </FRAMESET>
    
</FRAMESET>
</HTML>