style.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
.container {
    width: 100vw;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}
.loader {
    height: 40px;
    width: 140px;
}
.dot {
    width: 16px;
    height: 16px;
    position: relative;
    top: 12px;
    background: #000;
    border-radius: 50%;
    animation: dot 2.8s infinite;
}
.dots {
    margin-top: 12px;
    margin-left: 31px;
    animation: dots 2.8s infinite;
}
span {
    display: block;
    float: left;
    width: 16px;
    height: 16px;
    margin-left: 16px;
    background: #000;
    border-radius: 50%;
}
@keyframes dot { 
    50% { 
        transform: translateX(96px);
    }
}
@keyframes dots { 
    50% { 
        transform: translateX(-31px);
    }
}