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

.loader {
    width: 5em;
    height: 13em;
    font-size: 10px;
    display: flex;
    flex-direction: column;
}

/* ball */
.loader::before {
    content: '';
    width: 5em;
    height: 5em;
    background-color: orangered;
    border-radius: 50%;
    animation: ball-jumping 0.5s ease-in-out infinite alternate;
}

@keyframes ball-jumping {
    40% {
        transform: translateY(-2em);
    }

    100% {
        transform: translateY(calc((8em - 5em) / 2));
    }
}

/* rectangle */
.loader::after {
    content: '';
    width: 5em;
    height: 8em;
    background-color: orange;
    border-radius: 0.5em;
    animation: rect-rotating 1s ease-in-out infinite;
}

@keyframes rect-rotating {
    50% {
        transform: rotate(90deg);
    }

    100% {
        transform: rotate(180deg);
    }
}