body {
    font-family: 'Noto Sans JP', sans-serif;
    color: #e2e8f0;
    background-color: #050510;
    display: flex;
    flex-direction: column;
    height: 100dvh;
    overflow: hidden;
}

@keyframes cosmicFlow {
    0% { transform: scale(1) translate(0, 0); opacity: 0.3; }
    50% { transform: scale(1.1) translate(3%, 3%); opacity: 0.5; }
    100% { transform: scale(1) translate(0, 0); opacity: 0.3; }
}

@keyframes deepAbyss {
    0% { transform: rotate(0deg) scale(1); }
    50% { transform: rotate(180deg) scale(1.2); }
    100% { transform: rotate(360deg) scale(1); }
}

.nebula-layer {
    position: fixed;
    inset: -50%;
    background: 
        radial-gradient(circle at 30% 30%, rgba(88, 28, 135, 0.4) 0%, transparent 40%),
        radial-gradient(circle at 70% 60%, rgba(2, 66, 82, 0.4) 0%, transparent 45%),
        radial-gradient(circle at 50% 80%, rgba(15, 23, 42, 0.8) 0%, transparent 60%);
    z-index: -30;
    animation: deepAbyss 40s linear infinite;
    pointer-events: none;
}

.star-dust {
    position: fixed;
    inset: 0;
    z-index: -20;
    background-image: url('data:image/svg+xml,%3Csvg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg"%3E%3Cfilter id="noise"%3E%3CfeTurbulence type="fractalNoise" baseFrequency="0.8" numOctaves="3" stitchTiles="stitch"/%3E%3C/filter%3E%3Crect width="100%25" height="100%25" filter="url(%23noise)" opacity="0.3"/%3E%3C/svg%3E');
    mix-blend-mode: color-dodge;
    opacity: 0.15;
    pointer-events: none;
}

.cosmic-card {
    position: relative;
    overflow: hidden;
    background: rgba(15, 20, 35, 0.4);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-top: 1px solid rgba(255, 255, 255, 0.15);
    border-left: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 16px;
    box-shadow: 
        0 15px 35px rgba(0, 0, 0, 0.6),
        inset 0 0 20px rgba(0, 0, 0, 0.5);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.cosmic-card::before {
    content: '';
    position: absolute;
    top: -50%; left: -50%; width: 200%; height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.05) 0%, transparent 60%);
    animation: cosmicFlow 10s infinite alternate ease-in-out;
    pointer-events: none;
}

.cosmic-card:active, .museum-item:active {
    transform: translateY(2px) scale(0.97);
    background: rgba(20, 25, 45, 0.6);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.8);
    border-color: rgba(255, 255, 255, 0.2);
}

.plasma-sphere {
    position: relative;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 
        0 0 15px currentColor,
        inset 0 2px 5px rgba(255, 255, 255, 0.6),
        inset 0 -5px 15px rgba(0, 0, 0, 0.5);
    transition: transform 0.3s ease, filter 0.3s ease;
}

.plasma-sphere::after {
    content: '';
    position: absolute;
    top: 8%; left: 15%; width: 35%; height: 35%;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.8) 0%, transparent 100%);
    border-radius: 50%;
    filter: blur(1px);
}

.group:hover .plasma-sphere {
    transform: scale(1.08);
    filter: brightness(1.2);
}

.icon-glow {
    filter: drop-shadow(0 0 6px white) drop-shadow(0 0 12px currentColor);
}
.museum-item.active {
    background: rgba(40, 50, 80, 0.7);
    border-color: rgba(100, 120, 255, 0.5);
    transform: scale(1.02);
}