body {
    margin: 0;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(black, midnightblue);
    overflow: hidden;
}

.spacecraft {
    width: 11em;
    height: 15em;
    position: relative;
}

.body {
    position: absolute;
    width: 7em;
    height: 11em;
    left: 2em;
    background: linear-gradient(whitesmoke, darkgray);
    border-radius: 50% / 70% 70% 5% 5%;
    z-index: 1;
}

.body::before {
    content: '';
    position: absolute;
    box-sizing: border-box;
    width: 4em;
    height: 4em;
    background-color: deepskyblue;
    border-radius: 50%;
    border: 0.5em solid lightslategray;
    box-shadow: inset -0.2em 0.2em white;
    top: 3em;
    left: 1.5em;
}

.engine {
    position: absolute;
    width: 6em;
    height: 2em;
    background-color: #444;
    border-radius: 20%;
    top: 10em;
    left: 2.5em;
}

.engine::before {
    content: '';
    position: absolute;
    box-sizing: border-box;
    width: 4em;
    height: 4em;
    background: gold;
    border-radius: 80% 0 50% 45% / 50% 0 80% 45%;
    transform: rotate(135deg);
    border: 0.5em solid orange;
    left: 1em;
    z-index: -1;
    animation: flame-spout 0.3s infinite;
}

@keyframes flame-spout {
    0%, 100% {
        filter: opacity(0.1);
    }

    50% {
        filter: opacity(1);
    }
}

.fins::before,
.fins::after {
    content: '';
    position: absolute;
    width: 2em;
    height: 6em;
    background: linear-gradient(tomato, darkred);
    top: 7em;
}

.fins::before {
    left: 0;
    border-radius: 3em 0 50% 100%;
}

.fins::after {
    right: 0;
    border-radius: 0 3em 100% 50%;
}

.stars span {
    position: absolute;
    width: calc(var(--size) * 1px);
    height: calc(var(--size) * 4px);
    border-radius: 50%;
    background-color: white;
    filter: opacity(var(--opacity));
    top: -5vh;
    left: calc(var(--left) * 1vw);
    animation: star-move linear infinite;
    animation-duration: calc(var(--duration) * 1s);
    animation-delay: calc(var(--delay) * 1s);
}

@keyframes star-move {
    to {
        top: 100vh;
    }
}