body {
    margin: 0;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: lightyellow;
}

.loader {
    width: 30em;
    height: 3em;
    font-size: 10px;
    position: relative;
}

.loader::before,
.loader::after {
    content: 'loading';
    position: absolute;
    width: 50%;
    height: inherit;
    border-radius: 1em;
    font-size: 2.5em;
    color: white;
    text-align: center;
    line-height: 1em;
    animation: 5s move ease-in-out infinite;
    mix-blend-mode: multiply;
}

.loader::before {
    left: 0;
    background-color: dodgerblue;
    --direction: 1;
}

.loader::after {
    right: 0;
    background-color: hotpink;
    --direction: -1;
}

@keyframes move {
    50% {
        transform: translateX(calc(100% * var(--direction)));
    }
}