@keyframes bubbleRise {
    0% {
        bottom: 10%;
        opacity: 0.5;
    }
    100% {
        bottom: 100%;
        opacity: 0;
    }
}

body {
    overflow: hidden;
    position: relative;
    margin: 0;
    height: 100vh;
    background: linear-gradient(to bottom, #0099FF 0%, #0099FF 80%, #E0C080 80%, #E0C080 100%); /* 80% blue for ocean, 20% for sea floor */
}

/* Surface Waves */
body::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 10px;
    background: repeating-linear-gradient(45deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.2) 10px, transparent 10px, transparent 20px);
    z-index: 10;  /* make sure it's above the fish */
}

/* Bubbles */
body::after, .fish::before, .fish::after {
    content: '';
    position: absolute;
    bottom: 10%;
    background-color: #fff;
    border-radius: 50%;
    animation: bubbleRise 4s infinite;
    opacity: 0;
}

body::after {
    right: 10%;
    width: 20px;
    height: 20px;
}


.fish {
    position: absolute;
    transition: all 2s ease;
    width: 100px; /* this width can be adjusted to your base desired fish width */
    height: auto;
}

.fish img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}