.particle {
    left: 0px;
    top: 0px;
    position: fixed;

    background-repeat: no-repeat;
    background-size: contain;

    image-rendering: -moz-crisp-edges; /* Firefox */
	image-rendering: -o-crisp-edges; /* Opera */
	image-rendering: -webkit-optimize-contrast; /* Webkit (non-standard naming) */
	image-rendering: pixelated;
	-ms-interpolation-mode: nearest-neighbor;
    
    transition: transform linear 1s;
    z-index: -10;
}

.asteroid0 {
    background-image: url('../sprites/particles/asteroid_1.webp');
}

.asteroid1 {
    background-image: url('../sprites/particles/asteroid_2.webp');
}

.asteroid2 {
    background-image: url('../sprites/particles/asteroid_3.webp');
}

.asteroid3 {
    background-image: url('../sprites/particles/asteroid_4.webp');
}

.star0 {
    background-image: url('../sprites/particles/star_1.webp');
}

.star1 {
    background-image: url('../sprites/particles/star_2.webp');
}

.star2 {
    background-image: url('../sprites/particles/star_3.webp');
}

@keyframes starBlink {
    0% {
        opacity: .666;
    }
    50% {
        opacity: .15;
    }
    100% {
        opacity: .666;
    }
}