banner-container {
   width: 1200px;
   height: 400px;
   margin: 1rem auto;
   overflow: hidden;
   position: relative;
}
banner-container .banner-img-container {
   width: 6000px; /* 假设有5张图片 */
   height: 400px;
   position: absolute;
   display: flex;
}
@keyframes run {
   0%, 10% { transform: translateX(0); }
   20%, 30% { transform: translateX(-1200px); }
   /* 更多关键帧 */
   100% { transform: translateX(0); }
}