:root {
    --bg: #ffffff;
    --node: 0,150,255;
    --glow: rgba(0,150,255,.35);
}

body.dark {
    --bg: #0d1117;
    --node: 0,200,255;
    --glow: rgba(0,200,255,.6);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background: var(--bg);
    overflow: hidden;
    font-family: system-ui, sans-serif;
    transition: background .3s ease;
}

canvas {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
}

#bg { z-index: 0; }
#network { z-index: 1; }

.container {
    position: relative;
    z-index: 3;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.logo {
    width: 320px;
    max-width: 80vw;
    transition: transform .2s ease, filter .3s ease;
}

.logo:hover {
    filter: drop-shadow(0 0 30px var(--glow));
}

/* Toggle */

#theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 5;
    background: rgba(255,255,255,.6);
    backdrop-filter: blur(8px);
    border: none;
    border-radius: 30px;
    padding: 8px 12px;
    font-size: 16px;
    cursor: pointer;
    transition: .2s ease;
}

body.dark #theme-toggle {
    background: rgba(20,20,20,.6);
    color: white;
}

#theme-toggle:hover {
    transform: scale(1.05);
}

/* Preloader */

#preloader {
    position: fixed;
    inset: 0;
    background: var(--bg);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    transition: opacity .6s ease;
}

#preloader img {
    width: 160px;
    animation: pulse 1.5s infinite ease-in-out;
}

@keyframes pulse {
    0% { transform: scale(1); opacity: .6; }
    50% { transform: scale(1.05); opacity: 1; }
    100% { transform: scale(1); opacity: .6; }
}