h1 {
  font-family: sans-serif;
  font-size: 50px;
  font-weight: normal;
  text-align: center;
}

.container {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  margin-top: 50px;
}

.slider {
  width: 512px;
  height: 128px;
  border: 5px solid #0b99ff;
  overflow: hidden;
}

#img-list {
  width: 1024px;
  position: relative;
  left: 0;
  -webkit-transition: all ease 1s;
  transition: all ease 1s;
}
#img-list::after {
  content: "";
  display: block;
  clear: both;
}
#img-list img {
  float: left;
}