.loader{
    width: 200px;
    height: 100px;
    margin: 0 auto;
    position: relative;
}

.loader:after{
    content: "";
    width: 2px;
    height: 100px;
    margin-left: -1px;
    border-left: 2px dotted #000;
    position: absolute;
    left: 50%;
    z-index: 1;
}

.loader-box-left,
.loader-box-right{
    width: 100px;
    height: 100px;
    overflow: hidden;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 2;
}

.loader-box-right{
    left: auto;
    right: 0
}

.loader-circle-left,
.loader-circle-right{
    background: #e74c3c;
    width: 75px;
    height: 75px;
    margin-top: -37.5px;
    border-radius: 50%;
    border: 2px solid #000;
    position: absolute;
    top: 50%;
    right: 10px;
    z-index: 3;
    animation: leftAnim 1.3s ease-in-out alternate infinite;
}

 .loader-circle-right{
    background: #8e44ad;
    right: auto;
    left: 10px;
    z-index: 2;
    animation: rightAnim 1.3s ease-in-out alternate infinite;
}

 @keyframes leftAnim{
    0%{ transform: translateX(97px); }
    100%{ transform: translateX(0); }
}

 @keyframes rightAnim{
    0%{ transform: translateX(0); }
    100%{ transform: translateX(-93px); }
}