*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body{
    display: flex;
    justify-content: center;
    align-items: center;
    background: #edf1f4;
    min-height: 100vh;
}
.loader{
    display: flex;
    flex-direction: row;
}
.loader .box{
    position: relative;
    height: 200px;
    width: 40px;
    margin: 30px;
    overflow: hidden;
    border-radius: 40px;
    border: 2px solid #edf1f4;
    background: linear-gradient(to bottom, rgba(0,0,0,0.05), #edf1f4);
    box-shadow: 15px 15px 15px rgba(0, 0, 0,0.1),
                -15px -15px 20px #ffffff,
                inset -5px -5px 5px rgba(255,255, 255,0.5),
                inset 5px 5px 5px rgba(0, 0, 0, 0.05);
}
.loader .box::before{
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 10;
    border-radius: 40px;
    box-shadow: 15px 15px 15px rgba(0, 0, 0, 0.1),
                -15px -15px 20px #ffffff,
                inset -5px -5px 5px rgba(255, 255, 255, 0.5),
                inset 5px 5px 5px rgba(0, 0, 0, 0.05); ;
}
.loader .box::after{
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 36px;
    height: 36px;
    background-color: #ffffff;
    border-radius: 50%;
    box-shadow: inset -5px -5px 5px rgba(0, 0, 0, 0.2),
                0 420px 0 400px #2196f3;
    animation: animate 2.5s ease-in-out infinite;
    transform: translateY(160px);
    animation-delay:calc(-0.3s * var(--i)) ;
}
@keyframes animate{
    0% {
            transform: translateY(160px);
                filter: hue-rotate(180deg);
        }
                 50% {
                     transform: translateY(0px);
                 }
                                  100% {
                                      transform: translateY(160px);
                                        filter: hue-rotate(0deg);
                                  }
}