.slider_container {
  position: relative;
  padding-bottom: 400px;
}
.slider_container div {
  position: absolute;
  width: 100%;
  text-align: center;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  opacity: 0;
  filter: alpha(opacity=0);
  -webkit-animation: round 20s linear infinite;
  animation: round 20s linear infinite;
}
@-webkit-keyframes round {
  5% {
    opacity: 1;
    filter: alpha(opacity=100);
    /* 0-1秒淡入 */
  }
  25% {
    opacity: 1;
    filter: alpha(opacity=100);
    /* 1-5秒靜止 */
  }
  30% {
    opacity: 0;
    filter: alpha(opacity=0);
    /* 5-6秒淡出 */
  }
}
@keyframes round {
  5% {
    opacity: 1;
    filter: alpha(opacity=100);
    /* 0-1秒淡入 */
  }
  25% {
    opacity: 1;
    filter: alpha(opacity=100);
    /* 1-5秒靜止 */
  }
  30% {
    opacity: 0;
    filter: alpha(opacity=0);
    /* 5-6秒淡出 */
  }
}
.slider_container div:nth-child(1) {
  -webkit-animation-delay: 0s;
  animation-delay: 0s;
}
.slider_container div:nth-child(2) {
  -webkit-animation-delay: 5s;
  animation-delay: 5s;
}
.slider_container div:nth-child(3) {
  -webkit-animation-delay: 10s;
  animation-delay: 10s;
}
.slider_container div:nth-child(4) {
  -webkit-animation-delay: 15s;
  animation-delay: 15s;
}