/* --- Ensure HTML and Body use full size of the viewport --- */
html {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
    overscroll-behavior: none;
}

/* --- Subtle Background Color Animation --- */
@keyframes subtle-color-shift {
    0% { background-color: #000000; }
    25% { background-color: #0C0618; }
    50% { background-color: #040C18; }
    75% { background-color: #180C04; }
    100% { background-color: #000000; }
}

body {
    height: 100vh;
    width: 100%;
    min-height: 100vh;
    margin: 0;
    padding: 0;

    font-family: 'Inter', sans-serif;
    background-color: #000000;
    animation: subtle-color-shift 60s infinite alternate;
    overflow: hidden;
    overscroll-behavior: none;
    cursor: default;
    position: relative;
}

@supports (height: 100dvh) {
    body {
        height: 100dvh;
        min-height: 100dvh;
    }
}

/* --- Layout & Core --- */
#void-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

#star-canvas {
    position: absolute;
    top: 0;
    left: 0;
    z-index: 5;
    pointer-events: none;
    opacity: 1;
    image-rendering: -webkit-optimize-contrast;
}

#splash-screen {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    background-color: rgba(0, 0, 0, 0.95);
    z-index: 1000;
    transition: opacity 2.8s ease-out;
    pointer-events: none;
}

#splash-icon {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 1.25em;
    line-height: 1;

    font-size: clamp(2rem, 10vw, 8rem);
    color: #ffffff;
    animation: pulse 2s infinite;
    z-index: 1001;
    cursor: pointer;

    will-change: transform, opacity;
    transition: transform 3s ease, opacity 1s ease-out;
}

@media (hover: none), (pointer: coarse) {
    #splash-icon {
        width: 0.95em;
    }
}

#splash-icon.corner-toggle-hover {
    opacity: 0.2;
    transition: transform 3s ease, opacity 0.2s ease-in-out;
}

#splash-icon.corner-toggle-hover.no-transition {
    transition: opacity 0.2s ease-in-out;
}

@media (hover: hover) and (pointer: fine) {
    #splash-icon.corner-toggle-hover:hover {
        opacity: 1.0;
    }
}

#splash-icon.corner-toggle-hover.tap-active {
    opacity: 1.0;
}

@keyframes pulse {
    0% { transform: translate(-50%, -50%) scale(1); opacity: 0.8; }
    50% { transform: translate(-50%, -50%) scale(1.1); opacity: 1.0; }
    100% { transform: translate(-50%, -50%) scale(1); opacity: 0.8; }
}

#volume-control {
    position: fixed;
    left: 0;
    top: 0;
    z-index: 1002;
    opacity: 0;
    transform: translate(-50%, calc(-100% + 8px));
    transition: opacity 0.35s ease, transform 0.35s ease;
    pointer-events: none;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 10px 8px;
    background: rgba(0, 0, 0, 0.35);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 999px;
    backdrop-filter: blur(4px);
}

#volume-control.visible {
    opacity: 0.7;
    transform: translate(-50%, -100%);
    pointer-events: auto;
}

#volume-control:hover,
#volume-slider:focus-visible {
    opacity: 1;
}

#volume-slider {
    width: 4px;
    height: clamp(80px, 15vh, 120px);
    accent-color: #ffffff;
    cursor: pointer;
    writing-mode: bt-lr;
    appearance: slider-vertical;
    -webkit-appearance: slider-vertical;
}

@media (hover: none), (pointer: coarse) {
    #volume-control {
        display: none !important;
    }
}