.scroll-img {
  width: 1100px;
  height: 400px;
  overflow: hidden;
  font-size: 0;
}
.scroll-img ul {
  width: 700px;
  height: 400px;
  margin: 0;
}
.scroll-img ul li {
  display: inline-block;
  margin: 10px 0 10px 10px;
}
#demo4.scroll-img ul {
  width: 1200px;
}