:root { color-scheme: dark; }

html,
body {
  width: 100%;
  min-height: 100%;
  margin: 0;
  overflow: hidden;
  background: var(--brand-pitch);
  font-family: var(--type-editorial);
}

body {
  min-height: 100vh;
  min-height: 100dvh;
}

#viz {
  display: block;
  width: 100vw;
  height: 100vh;
  height: 100dvh;
  touch-action: manipulation;
}

#toast {
  position: fixed;
  z-index: 10;
  bottom: calc(126px + env(safe-area-inset-bottom));
  left: 50%;
  max-width: calc(100vw - 32px);
  padding: 10px 14px;
  transform: translateX(-50%);
  overflow: hidden;
  background: rgba(36, 36, 36, 0.94);
  border: 1px solid var(--brand-concrete);
  color: var(--brand-paper);
  font-family: var(--type-utility);
  font-size: 11px;
  opacity: 0;
  pointer-events: none;
  text-overflow: ellipsis;
  transition: opacity 0.25s ease;
  white-space: nowrap;
}

#toast.show { opacity: 1; }

#controls {
  position: fixed;
  z-index: 10;
  right: 12px;
  bottom: calc(12px + env(safe-area-inset-bottom));
  left: 12px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
  padding: 10px;
  border-left: 5px solid var(--brand-concrete);
  background: rgba(234, 231, 225, 0.96);
  box-shadow: 8px 8px 0 rgba(116, 119, 122, 0.45);
  color: var(--brand-pitch);
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.25s ease, transform 0.25s ease;
}

body.running #controls {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

body.controls-idle #controls {
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
}

#controls button {
  min-height: 52px;
  padding: 8px 10px;
  border: 1px solid var(--brand-pitch);
  border-radius: 0;
  background: transparent;
  color: var(--brand-pitch);
  cursor: pointer;
  font-family: var(--type-utility);
  font-size: 11px;
  font-weight: 700;
  line-height: 1.2;
  text-transform: uppercase;
  touch-action: manipulation;
}

#controls button span,
#controls button strong {
  display: block;
}

#controls button strong {
  margin-top: 4px;
  font-size: 14px;
}

#controls button:active,
#controls button:focus-visible {
  background: var(--brand-pitch);
  color: var(--brand-paper);
}

#controls button:disabled {
  cursor: not-allowed;
  opacity: 0.35;
}

body.hyperspeed #hyperspeedBtn {
  background: var(--brand-pitch);
  color: var(--brand-paper);
}

#help {
  position: fixed;
  z-index: 20;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  background: rgba(11, 11, 11, 0.88);
  color: var(--brand-paper);
  text-align: center;
  transition: opacity 0.4s ease;
}

#help.hidden {
  opacity: 0;
  pointer-events: none;
}

#help .box {
  width: min(100%, 440px);
  max-height: calc(100vh - 32px);
  max-height: calc(100dvh - 32px);
  box-sizing: border-box;
  overflow: auto;
  padding: clamp(24px, 8vw, 42px);
  border-left: 6px solid var(--brand-concrete);
  background: var(--brand-paper);
  box-shadow: 8px 8px 0 rgba(116, 119, 122, 0.45);
  color: var(--brand-pitch);
}

#help .eyebrow {
  margin: 0 0 18px;
  color: var(--brand-charcoal);
  font-family: var(--type-utility);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

#help h1 {
  margin: 0;
  font-family: var(--type-display);
  font-size: clamp(2.4rem, 13vw, 4rem);
  font-weight: var(--weight-display);
  letter-spacing: -0.07em;
  line-height: 0.9;
}

#help p {
  margin: 16px 0 28px;
  color: var(--brand-charcoal);
  font-size: 14px;
  line-height: 1.5;
}

#help .go,
#startupStatus {
  color: var(--brand-pitch);
  font-family: var(--type-utility);
  font-size: 13px;
  font-weight: 700;
}

@media (min-width: 640px) {
  #controls {
    right: auto;
    left: 50%;
    width: min(640px, calc(100vw - 24px));
    grid-template-columns: repeat(4, minmax(0, 1fr));
    transform: translate(-50%, 12px);
  }

  body.running #controls { transform: translate(-50%, 0); }
  body.controls-idle #controls { transform: translate(-50%, 12px); }
}

@media (max-height: 440px) {
  #controls { padding: 6px; }
  #controls button { min-height: 44px; }
  #controls button strong { display: inline; margin: 0 0 0 4px; }
  #toast { bottom: calc(88px + env(safe-area-inset-bottom)); }
}

@media (prefers-reduced-motion: reduce) {
  #controls,
  #toast,
  #help { transition: none; }
}