body {
    background-color: #f3f4fa;
}

body::after {
    content: "";
    position: absolute;
    top: 42%;
    left: 50%;

    display: flex;
    flex-direction: column;
    justify-content: center;
    width: 38%;
    height: 1rem;

    transform: translate(-50%, -42%);
    background-color: #315ee3;

    overflow: hidden;
    text-align: center;
    white-space: nowrap;
    background-image: linear-gradient(45deg,hsla(0,0%,100%,.15) 25%,transparent 0,transparent 50%,hsla(0,0%,100%,.15) 0,hsla(0,0%,100%,.15) 75%,transparent 0,transparent);
    background-size: 1rem 1rem;
    animation: progress-bar-stripes 1s linear infinite;
    transition: width .6s ease;
    border-radius: 4px;
}