.underwater-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: 9999;
    overflow: hidden;
    contain: strict;
}

.underwater-bg {
    position: absolute;
    top: 0; left: 0; width: 100vw; height: 100vh;
    background: linear-gradient(180deg, rgba(0, 105, 148, 0.1) 0%, rgba(0, 48, 143, 0.4) 100%);
    pointer-events: none;
    z-index: 10;
}

.underwater-symbol {
    position: absolute;
    animation-timing-function: linear;
    animation-iteration-count: infinite;
    font-size: 3rem;
    opacity: 0.9;
    z-index: 20;
}

.underwater-symbol img {
    width: 6vh;
    height: auto;
    max-width: 60px;
    object-fit: contain;
}

.underwater-seaweed {
    will-change: transform, opacity;
    position: absolute;
    bottom: -1vh;
    font-size: 4rem;
    transform-origin: bottom center;
    animation: underwater-sway 4s ease-in-out infinite alternate;
    z-index: 30;
    opacity: 0.8;
}

.underwater-seaweed img {
    height: 12vh;
    width: auto;
    object-fit: contain;
    max-height: 120px;
}

.underwater-bubble {
    will-change: transform;
    position: absolute;
    bottom: -5vh;
    border-radius: 50%;
    border: 1px solid rgba(255, 255, 255, 0.4);
    background: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0.1));
    box-shadow: inset 0 0 5px rgba(255, 255, 255, 0.5);
    animation: underwater-bubble-rise linear infinite;
    z-index: 40;
}

@keyframes underwater-traverse-right {
    0% { left: -25vw; }
    100% { left: 125vw; }
}

@keyframes underwater-traverse-left {
    0% { left: 125vw; }
    100% { left: -25vw; }
}

@keyframes underwater-traverse-up {
    0% { top: 0;  translate: 0 120vh; }
    100% { top: 0;  translate: 0 -20vh; }
}

@keyframes underwater-traverse-down {
    0% { top: 0;  translate: 0 -20vh; }
    100% { top: 0;  translate: 0 120vh; }
}

@keyframes underwater-sway-y {
    0% { transform: translateY(-2vh); }
    100% { transform: translateY(2vh); }
}

@keyframes underwater-sway {
    0% { transform: rotate(-10deg); }
    100% { transform: rotate(10deg); }
}

@keyframes underwater-bubble-rise {
    0% { transform: translateY(0) translateX(0); opacity: 0; }
    10% { opacity: 0.7; }
    50% { transform: translateY(-55vh) translateX(-20px); }
    90% { opacity: 0; }
    100% { transform: translateY(-110vh) translateX(10px); opacity: 0; }
}

.underwater-god-rays {
    will-change: transform;
    position: absolute;
    top: 0;
    left: -50vw;
    width: 200vw;
    height: 200vh;
    background: repeating-linear-gradient(
        15deg,
        rgba(255, 255, 255, 0.02) 0px,
        rgba(255, 255, 255, 0.05) 100px,
        transparent 100px,
        transparent 300px
    );
    animation: god-rays-sway 20s ease-in-out infinite alternate;
    pointer-events: none;
    z-index: 12;
    transform-origin: top center;
    mix-blend-mode: overlay;
    filter: blur(5px);
    translate: 0 -50vh;
}

@keyframes god-rays-sway {
    0% { transform: rotate(-3deg) translateX(-5%); opacity: 0.4; }
    50% { opacity: 0.8; }
    100% { transform: rotate(3deg) translateX(5%); opacity: 0.4; }
}