img iframe{
  src:"https://pic.jschina.com.cn/0/21/82/84/21828447_062354.jpg"
}
#site_nav_under {
    display: none;
}
.c_ad_block, .ad_text_commentbox {
    display: none;
    margin: 0;
    padding: 0;
}
#ad_under_google {
    height: 0;
    overflow: hidden;
}
#ad_under_google a {
    display: none;
}