body, html {
    height: 100%;
    margin: 0;
    overflow: hidden;
    font-family: Arial, sans-serif;
    background: #1a1a1a;
}
.content {
    position: relative;
    z-index: 1;
    color: white;
    text-align: center;
    padding-top: 20vh;
}
.bubble {
    position: absolute;
    border-radius: 50%;
    background: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0.4));
    animation: rise 15s infinite ease-in;
    opacity: 0;
}
@keyframes rise {
    0% {
        bottom: -100px;
        opacity: 0;
    }
    50% {
        opacity: 0.8;
    }
    100% {
        bottom: 100%;
        opacity: 0;
    }
}
.mouse-follower {
    position: fixed;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.5);
    pointer-events: none;
    mix-blend-mode: difference;
    transition: width 0.3s, height 0.3s;
    transform: translate(-50%, -50%);
}