.particles-container {
    position: fixed;
    top: 0;
    left: 0;
    pointer-events: none;
    width: 100%;
    height: 100%;
    z-index: -1;
}

.particle {
    position: absolute;
    border-radius: 50%;
    transform-origin: center center;
    animation: fadeInOut linear infinite;
}

@keyframes fadeInOut {
    0% {
        opacity: 0;
    }
    25% {
        opacity: 1;
    }
    75% {
        opacity: 1;
    }
    100% {
        opacity: 0;
    }
}