:root {
  --bg: #000;
  --nr: 57;
  --ng: 255;
  --nb: 20;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  overflow: hidden;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Inter, Arial, sans-serif;
}

/* Fondo neón fijo (sin movimiento) */
.bg-glow {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(50vmin 50vmin at 25% 25%, rgba(var(--nr),var(--ng),var(--nb),.25), transparent 80%),
    radial-gradient(45vmin 45vmin at 75% 75%, rgba(var(--nr),var(--ng),var(--nb),.2), transparent 80%),
    radial-gradient(60vmin 60vmin at 85% 20%, rgba(var(--nr),var(--ng),var(--nb),.15), transparent 90%);
  filter: blur(8px) saturate(120%);
  will-change: filter;
  z-index: 0;
}

/* Contenedor general */
main {
  position: relative;
  z-index: 1;
  width: 100%;
  height: 100vh;
  display: grid;
  place-items: center;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

/* Logo centrado */
.logo-wrap {
  display: grid;
  place-items: center;
  padding: clamp(6px, 2vmin, 16px);
  border-radius: 20px;
  box-shadow:
    0 0 0 2px rgba(57,255,20,.25) inset,
    0 0 16px rgba(57,255,20,.25),
    0 0 40px rgba(57,255,20,.15);
}

.logo {
  width: clamp(140px, 28vmin, 300px);
  height: auto;
  filter:
    drop-shadow(0 0 5px rgba(57,255,20,.2))
    drop-shadow(0 0 12px rgba(57,255,20,.15));
  z-index: 2;
  position: relative;
}

/* Canvas de pelotas */
#scene {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  cursor: grab;
  z-index: 3;
}