@media only screen and (max-width: 767px) {
  .content-section {
    margin-top: 0;
    padding: 65px 20px;
  }

  .about-img {
    width: 100%;
    background-image: url(https://hkgamestar.oss-cn-hongkong.aliyuncs.com/rongyao/assets/images/mobile/news-detail/bg3.png);
  }
}