:root {
  color-scheme: dark;
  --bg: #06081c;
  --ink: #eaf6ff;
  --muted: #9aa6d6;
  --accent: #5ee9ff;
  --violet: #7b5cff;
  --panel: rgba(12, 14, 44, 0.72);
  font-family:
    ui-rounded,
    system-ui,
    -apple-system,
    'Segoe UI',
    sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  background: var(--bg) url('./assets/backdrop.webp') center / cover fixed no-repeat;
  color: var(--ink);
}

.app {
  display: grid;
  gap: 10px;
  justify-items: center;
  max-width: 1040px;
  min-height: 100dvh;
  margin: 0 auto;
  padding: max(12px, env(safe-area-inset-top)) 16px max(16px, env(safe-area-inset-bottom));
  align-content: start;
}

.back {
  justify-self: start;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 2px;
  border-radius: 8px;
  color: var(--muted);
  text-decoration: none;
  font-size: 0.85rem;
  letter-spacing: 0.04em;
}

.back:hover {
  color: var(--ink);
}

.hud {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  gap: 12px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-size: clamp(1.15rem, 4.5vw, 1.5rem);
  letter-spacing: 0.03em;
  text-shadow: 0 0 18px rgba(94, 233, 255, 0.5);
}

.brand img {
  border-radius: 8px;
}

.stats {
  display: flex;
  gap: 16px;
  margin: 0;
}

.stats div {
  text-align: right;
}

.stats dt {
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.stats dd {
  margin: 0;
  font-size: 1.3rem;
  font-variant-numeric: tabular-nums;
}

.stage {
  position: relative;
  display: grid;
  place-items: center;
  width: 100%;
  height: min(64dvh, 620px);
  touch-action: none;
}

canvas {
  display: block;
  border-radius: 12px;
  box-shadow:
    0 0 0 1px rgba(94, 233, 255, 0.22),
    0 20px 60px rgba(0, 0, 0, 0.55),
    0 0 40px rgba(123, 92, 255, 0.15);
  cursor: crosshair;
}

canvas:focus-visible,
.back:focus-visible,
.btn:focus-visible,
select:focus-visible,
input:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

.intro {
  position: absolute;
  inset: 0;
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 10px;
  padding: 24px;
  text-align: center;
  border-radius: 12px;
  background: radial-gradient(circle at 50% 40%, rgba(6, 8, 28, 0.55), rgba(6, 8, 28, 0.88));
  backdrop-filter: blur(2px);
}

.intro[hidden] {
  display: none;
}

.intro img {
  width: clamp(88px, 22vmin, 140px);
  height: auto;
  border-radius: 22%;
  filter: drop-shadow(0 0 24px rgba(94, 233, 255, 0.35));
}

.intro h2 {
  margin: 0;
  font-size: clamp(1.4rem, 5vw, 2.2rem);
  text-shadow: 0 0 22px rgba(94, 233, 255, 0.55);
}

.intro p {
  margin: 0;
  max-width: 42ch;
  color: var(--muted);
}

.controls {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px 14px;
  align-items: center;
}

.btn {
  font: inherit;
  font-weight: 600;
  color: var(--ink);
  background: var(--panel);
  border: 1px solid rgba(94, 233, 255, 0.3);
  border-radius: 999px;
  padding: 8px 18px;
  min-height: 44px;
  cursor: pointer;
}

.btn.primary {
  background: linear-gradient(180deg, #7af4ff, #2bb6d9);
  color: #031420;
  border: 0;
  min-width: 96px;
}

.btn:disabled {
  opacity: 0.45;
  cursor: default;
}

.field {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  color: var(--muted);
}

select {
  font: inherit;
  color: var(--ink);
  background: var(--panel);
  border: 1px solid rgba(94, 233, 255, 0.3);
  border-radius: 10px;
  padding: 8px 10px;
  min-height: 40px;
}

input[type='range'] {
  accent-color: var(--accent);
  width: 120px;
}

input[type='checkbox'] {
  accent-color: var(--accent);
  width: 18px;
  height: 18px;
}

output {
  min-width: 3.5ch;
  font-variant-numeric: tabular-nums;
  color: var(--ink);
}

.hint {
  margin: 0;
  font-size: 0.8rem;
  color: var(--muted);
}

@media (pointer: coarse) {
  .hint {
    display: none;
  }
  .stage {
    height: min(56dvh, 620px);
  }
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition: none !important;
    animation: none !important;
  }
  .intro {
    backdrop-filter: none;
  }
}

@media (max-width: 420px) {
  .controls .btn {
    padding-inline: 13px;
  }
  .btn.primary {
    min-width: 80px;
  }
}