body {
    margin: 0;
    height: 100vh;
    background-color: black;
}

.monster {
    width: 100vw;
    height: 50vh;
    background-color: lightcyan;
    position: relative;
    overflow: hidden;
}

.body {
    position: absolute;
    width: 32vmin;
    height: 32vmin;
    background-color: teal;
    border-radius: 43% 40% 43% 40%;
    bottom: calc(-1 * 32vmin / 2 - 4vmin);
    left: -2vmin;
    animation:
        wander 5s linear infinite alternate,
        wave 3s linear infinite,
        bounce 1s infinite alternate;
}

.eyes {
    width: 24vmin;
    height: 5vmin;
    position: absolute;
    bottom: 2vmin;
    left: calc(32vmin - 24vmin - 2vmin);
    animation: wander 5s linear infinite alternate;
}

.eyes::before,
.eyes::after {
    content: '';
    position: absolute;
    width: 5vmin;
    height: 5vmin;
    border: 1.25vmin solid white;
    box-sizing: border-box;
    border-radius: 50%;
    animation: blink 3s linear infinite;
}

.eyes::before {
    left: 4vmin;
}

.eyes::after {
    right: 4vmin;
}

@keyframes bounce {
    to {
        bottom: calc(-1 * 32vmin / 2 - 2vmin);
    }
}

@keyframes wave {
    to {
        transform: rotate(1turn);
    }
}

@keyframes wander {
    to {
        left: calc(100vw - 32vmin + 2vmin);
    }
}

@keyframes blink {
    4%, 10%, 34%, 40% {
        transform: scaleY(1);
    }

    7%, 37% {
        transform: scaleY(0);
    }
}