/* ==========================================================================
   Nova Effects (Physical Mechanics & Space Distortions)
   ========================================================================== */

:root {
    --bh-core-color: #000000;
    --bh-theme-filter: invert(0);
}

@media (prefers-color-scheme: light) {
    :root {
        --bh-core-color: #ffffff;
        --bh-theme-filter: invert(1);
    }
}

/* --- Gemini Black Hole Visuals --- */
.nova-blackhole-container {
    position: absolute;
    transform: translate(-50%, -50%);
    z-index: 50;
    transition: opacity var(--duration-slow) var(--curve-smooth);
    width: 120px;
    height: 120px;
}

.central-mass { 
    fill: var(--bh-core-color); 
}

.inflow {
    fill: none;
    stroke-linecap: round;
    /* Dash array simulates clumpy matter, dash offset simulates flow */
    stroke-dasharray: 15 45;
    stroke-dashoffset: 0;
    animation: flowInward 10s linear infinite;
}

/* Animate flow inward along the spiral paths */
@keyframes flowInward {
    0% { stroke-dashoffset: 0; opacity: 0.8; }
    100% { stroke-dashoffset: 200; opacity: 0; }
}

/* Slow overall rotation of the system */
.rotating-disc {
    transform-origin: center;
    animation: rotateDisc 60s linear infinite;
}

@keyframes rotateDisc {
    to { transform: rotate(360deg); }
}

/* --- Supernova Explosion Flashes --- */
.nova-explosion {
    position: absolute;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #fff;
    transform: translate(-50%, -50%);
    pointer-events: none;
    z-index: 50;
    animation: explodeNova 0.4s cubic-bezier(0.1, 0.8, 0.2, 1) forwards;
}

@keyframes explodeNova {
    0% { transform: translate(-50%, -50%) scale(1); box-shadow: 0 0 20px 10px rgba(255,255,255,0.9); opacity: 1; }
    50% { transform: translate(-50%, -50%) scale(8); box-shadow: 0 0 50px 30px rgba(150,200,255,0.8); opacity: 0.9; }
    100% { transform: translate(-50%, -50%) scale(12); box-shadow: 0 0 100px 50px rgba(150,200,255,0); opacity: 0; }
}

/* --- Persistent Remnant Nebula --- */
.nova-remnant {
    position: absolute;
    width: 150px;
    height: 150px;
    border-radius: 50%;
    pointer-events: none;
    z-index: 5;
    transform: translate(-50%, -50%);
    animation: fadePulseRemnant 8s infinite alternate ease-in-out;
}

.nova-remnant::before {
    content: '';
    position: absolute;
    inset: -30px;
    border-radius: 50%;
    background: inherit;
    filter: blur(20px);
    opacity: 0.8;
}

.nova-remnant::after {
    content: '';
    position: absolute;
    top: 50%; left: 50%;
    width: 6px; height: 6px;
    background: #fff;
    border-radius: 50%;
    transform: translate(-50%, -50%);
    box-shadow: 0 0 15px 3px rgba(255,255,255,0.9), 0 0 30px 10px rgba(150,200,255,0.5);
    animation: twinkleStar 3s infinite alternate ease-in-out;
}

@keyframes twinkleStar {
    0% { transform: translate(-50%, -50%) scale(0.8); opacity: 0.7; }
    100% { transform: translate(-50%, -50%) scale(1.2); opacity: 1; }
}

@keyframes fadePulseRemnant {
    0% { transform: translate(-50%, -50%) scale(0.9) rotate(0deg); opacity: 0.6; }
    100% { transform: translate(-50%, -50%) scale(1.1) rotate(25deg); opacity: 1; }
}

@media (prefers-color-scheme: light) {
    .nova-explosion { background: #000; animation-name: explodeNovaLight; }
    @keyframes explodeNovaLight {
        0% { transform: translate(-50%, -50%) scale(1); box-shadow: 0 0 20px 10px rgba(0,0,0,0.9); opacity: 1; }
        50% { transform: translate(-50%, -50%) scale(8); box-shadow: 0 0 50px 30px rgba(50,50,50,0.8); opacity: 0.9; }
        100% { transform: translate(-50%, -50%) scale(12); box-shadow: 0 0 100px 50px rgba(50,50,50,0); opacity: 0; }
    }
}