:root {
  color-scheme: dark;
  --bg: #050018;
  --fg: #f5f7ff;
  --accent: #5c6bff;
  --accent-alt: #24e0ff;
  --card: rgba(10, 5, 32, 0.75);
  --card-border: rgba(180, 200, 255, 0.25);
  --safe: env(safe-area-inset-bottom, 16px);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: 'Inter', 'Segoe UI', system-ui, sans-serif;
  background: radial-gradient(circle at 20% 20%, rgba(44, 34, 94, 0.6), transparent),
              radial-gradient(circle at 80% 0%, rgba(12, 242, 255, 0.18), transparent),
              var(--bg);
  color: var(--fg);
  height: 100vh;
  overflow: hidden;
}

#app {
  position: relative;
  width: 100vw;
  height: 100vh;
  overflow: hidden;
}

.visualizer {
  position: absolute;
  inset: 0;
  overflow: hidden;
  touch-action: none;
}

.mode-layer {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.visual-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  mix-blend-mode: screen;
}

.hud {
  position: fixed;
  top: max(16px, env(safe-area-inset-top));
  left: 0;
  right: 0;
  padding: 0 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  pointer-events: none;
  z-index: 5;
}

.hud-row {
  display: flex;
  gap: 12px;
  justify-content: space-between;
}

.hud-card {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: 18px;
  padding: 10px 16px;
  min-width: 120px;
  backdrop-filter: blur(18px);
  pointer-events: auto;
}

.hud-label {
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  opacity: 0.75;
}

.hud-value {
  font-size: 1.6rem;
  font-weight: 600;
  margin-top: 4px;
}

.hud-small {
  font-size: 0.9rem;
  opacity: 0.8;
}

.hud-meter {
  position: relative;
  width: 100%;
  height: 6px;
  border-radius: 999px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.08);
  margin-top: 8px;
}

.hud-meter::after {
  content: '';
  position: absolute;
  inset: 0;
  transform-origin: left center;
  transform: scaleX(var(--level, 0));
  background: linear-gradient(90deg, var(--accent), var(--accent-alt));
  transition: transform 0.18s ease;
}

[data-hud="pulse"] {
  --level: var(--pulse-level, 0);
}

[data-hud="shield"] {
  --level: var(--shield-level, 1);
}

.toast {
  position: fixed;
  left: 50%;
  bottom: calc(80px + var(--safe));
  transform: translateX(-50%) translateY(40px);
  background: rgba(15, 12, 52, 0.8);
  border: 1px solid rgba(92, 107, 255, 0.45);
  padding: 12px 20px;
  border-radius: 999px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 6;
}

.toast.visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.controls {
  position: fixed;
  left: 0;
  right: 0;
  bottom: calc(16px + var(--safe));
  display: flex;
  justify-content: center;
  gap: 12px;
  pointer-events: none;
  z-index: 5;
}

.control-button {
  pointer-events: auto;
  border: 1px solid rgba(255, 255, 255, 0.15);
  background: rgba(15, 12, 52, 0.8);
  color: var(--fg);
  padding: 14px 18px;
  border-radius: 16px;
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  min-width: 120px;
  backdrop-filter: blur(18px);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.control-button:active {
  transform: translateY(2px);
  border-color: var(--accent);
}

@media (max-width: 768px) {
  .hud-row {
    flex-wrap: wrap;
  }
  .hud-card {
    flex: 1 1 calc(50% - 12px);
  }
  .control-button {
    min-width: 100px;
    font-size: 0.85rem;
  }
}

@media (max-width: 480px) {
  .hud-card {
    padding: 8px 12px;
    min-width: 100px;
  }
  .hud-value {
    font-size: 1.3rem;
  }
}