/* ============================================================
   MachineDog · EFFECTS — glass, glow, shadows, motion
   The Apple-glass + cyber-glow system. These are the brand's
   signature surface treatments.
   ============================================================ */
:root {
  /* ---- Glass primitives ---------------------------------- */
  --glass-bg:        hsl(0 0% 100% / 0.03);   /* faint frost fill */
  --glass-bg-strong: hsl(0 0% 100% / 0.05);
  --glass-ring:      hsl(0 0% 100% / 0.10);   /* inset hairline */
  --glass-highlight: hsl(0 0% 100% / 0.05);   /* top specular line */
  --glass-blur: 20px;
  --glass-saturate: 150%;

  /* ---- Shadows ------------------------------------------- */
  --shadow-sm: 0 2px 12px -1px hsl(220 60% 2% / 0.4);
  --shadow-md: 0 4px 24px -1px hsl(220 60% 2% / 0.5);
  --shadow-lg: 0 8px 32px -1px hsl(220 60% 2% / 0.6);
  --shadow-xl: 0 24px 64px -12px hsl(220 60% 2% / 0.7);
  --shadow-inset-top: inset 0 1px 0 var(--glass-highlight);

  /* ---- Cyber glow ---------------------------------------- */
  --glow-cyan-sm: 0 0 0 1px hsl(200 90% 60% / 0.35), 0 0 18px hsl(200 90% 60% / 0.45);
  --glow-cyan:    0 0 0 1px hsl(200 90% 60% / 0.35), 0 12px 60px -10px hsl(200 90% 60% / 0.45), 0 4px 18px -6px hsl(200 90% 60% / 0.5);
  --glow-violet:  0 0 0 1px hsl(254 95% 75% / 0.3), 0 0 32px -2px hsl(254 95% 75% / 0.4);
  --ring-cyan:    0 0 0 1px hsl(200 90% 60% / 0.4), 0 0 28px -2px hsl(200 90% 60% / 0.45);

  /* ---- Motion -------------------------------------------- */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1); /* @kind other */
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1); /* @kind other */
  --duration-fast: 150ms; /* @kind other */
  --duration: 300ms; /* @kind other */
  --duration-slow: 500ms; /* @kind other */
}

/* ---- Glass surface utilities ----------------------------- */
.md-glass {
  background: var(--glass-bg);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  box-shadow: inset 0 0 0 1px var(--glass-ring), var(--shadow-md), var(--shadow-inset-top);
  position: relative;
  overflow: hidden;
}
.md-glass-strong {
  background: var(--glass-bg-strong);
  -webkit-backdrop-filter: blur(28px) saturate(200%);
  backdrop-filter: blur(28px) saturate(200%);
  box-shadow: inset 0 0 0 1px hsl(0 0% 100% / 0.14), var(--shadow-lg), var(--shadow-inset-top);
  position: relative;
  overflow: hidden;
}
.md-glass-input {
  background: hsl(0 0% 100% / 0.04);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  box-shadow: inset 0 0 0 1px var(--glass-ring), inset 0 2px 6px hsl(220 60% 2% / 0.4);
}

/* ---- Background washes ----------------------------------- */
.md-bg-aurora {
  background-image: var(--gradient-aurora);
}
.md-bg-grid {
  background-image:
    radial-gradient(hsl(210 30% 92% / 0.10) 1px, transparent 1px),
    radial-gradient(hsl(210 30% 92% / 0.10) 1px, transparent 1px);
  background-size: 40px 40px;
  background-position: 0 0, 20px 20px;
}

/* ---- Husky eye pulse — the brand's one signature loop ----- */
@keyframes md-eye-pulse {
  0%, 100% { opacity: 0.55; filter: blur(0.5px); }
  50%      { opacity: 1;    filter: blur(0); }
}
.md-eye-pulse { animation: md-eye-pulse 2.4s var(--ease-in-out) infinite; will-change: opacity, filter; }

@keyframes md-aurora-drift {
  0%   { transform: scale(1) translate(0, 0); }
  50%  { transform: scale(1.1) translate(2%, -2%); }
  100% { transform: scale(1) translate(0, 0); }
}

@media (prefers-reduced-motion: reduce) {
  .md-eye-pulse { animation: none; opacity: 0.85; }
}