:root {
  --text: #f4f7ff;
  --board: #6e809b;
  --modal-ink: #e9f0ff;
  --modal-panel: var(--page-bg);
  --modal-button-color: #2f70dd;
  --modal-button-hover: #275fc0;
  --page-bg: #050d22;
  --sand: #c4a35a;
  --hud-color: var(--page-bg);
  --timer-color: var(--page-bg);
  --timer-track: rgba(5, 13, 34, 0.24);
  --button-color: #0079ff;
  --button-hover: #5c99ff;
  --button-text: white;
  --overlay-backdrop: rgba(7, 13, 30, 0.24);
  --viewport-inset-top: 0px;
  --viewport-inset-right: 0px;
  --viewport-inset-bottom: 0px;
  --viewport-inset-left: 0px;
  --safe-inset-top: max(env(safe-area-inset-top), var(--viewport-inset-top));
  --safe-inset-right: max(
    env(safe-area-inset-right),
    var(--viewport-inset-right)
  );
  --safe-inset-bottom: max(
    env(safe-area-inset-bottom),
    var(--viewport-inset-bottom)
  );
  --safe-inset-left: max(env(safe-area-inset-left), var(--viewport-inset-left));
  --app-padding-top: calc(var(--safe-inset-top) + 8px);
  --app-padding-bottom: calc(var(--safe-inset-bottom) + 8px);
  --app-padding-inline: 12px;
  --shell-gap: 10px;
  --footer-reserve: 28px;
  --board-inline-gutter: 10px;
  --board-top-gutter: 8px;
  --board-bottom-gutter: 18px;
  --font-sans:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial,
    sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html,
body {
  position: relative;
  width: 100%;
  min-height: 100%;
  overflow-x: hidden;
}

html {
  height: 100%;
  background: var(--page-bg);
}

body {
  --board-ui-reserve: calc(
    var(--app-padding-top) + var(--app-padding-bottom) + var(--shell-gap) +
      var(--footer-reserve) + var(--board-top-gutter) +
      var(--board-bottom-gutter)
  );
  overflow-y: auto;
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--page-bg);
}

#app {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 820px;
  margin: 0 auto;
  min-height: 100%;
  padding: var(--app-padding-top)
    calc(var(--app-padding-inline) + var(--safe-inset-right))
    var(--app-padding-bottom)
    calc(var(--app-padding-inline) + var(--safe-inset-left));
  display: grid;
  grid-template-rows: minmax(0, 1fr);
}

.overlay-card button {
  background: var(--modal-button-color);
}

.overlay-card button:hover {
  background: var(--modal-button-hover);
}

#game-container {
  position: relative;
  display: grid;
  place-items: start center;
  min-height: 0;
  padding: var(--board-top-gutter) 0 var(--board-bottom-gutter);
}
#game-shell {
  display: grid;
  width: 100%;
  grid-template-rows: auto auto;
  gap: var(--shell-gap);
  align-content: start;
  justify-items: center;
  opacity: 1;
  transition: opacity 140ms ease;
}


#canvas-wrap {
  position: relative;
  height: min(700px, calc(100vh - var(--board-ui-reserve)));
  height: min(700px, calc(100dvh - var(--board-ui-reserve)));
  height: min(700px, calc(100svh - var(--board-ui-reserve)));
  aspect-ratio: 39 / 70;
  width: auto;
  max-width: calc(100% - (var(--board-inline-gutter) * 2));
  margin-inline: auto;
  overflow: hidden;
  border: none;
  background: var(--board);
  touch-action: none;
}
header {
  text-align: center;
  margin-bottom: 0.5rem;
}

header h1 {
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text);
}

header h1::after {
  content: "";
  display: block;
  width: 24px;
  height: 2px;
  margin: 6px auto 0;
  background: var(--sand);
}

#game-canvas {
  display: block;
  width: 100%;
  height: 100%;
}
#score-display {
  position: absolute;
  top: auto;
  bottom: calc((58px - 1em) / 2 - 4px);
  right: 14px;
  font-size: 30px;
  line-height: 1;
  font-weight: 600;
  color: var(--hud-color);
  text-shadow: none;
  transition: color 260ms ease;
  pointer-events: none;
}

#timer-display {
  --timer-progress: 0;
  --timer-size: 28px;
  --timer-ring: 4px;
  position: absolute;
  top: auto;
  bottom: calc((58px - var(--timer-size)) / 2 - 4px);
  left: 14px;
  width: var(--timer-size);
  height: var(--timer-size);
  border-radius: 50%;
  overflow: hidden;
  background: conic-gradient(
    from -90deg,
    var(--timer-color) calc(var(--timer-progress) * 1turn),
    var(--timer-track) 0
  );
  border: none;
  -webkit-mask: radial-gradient(
    farthest-side,
    transparent calc(100% - var(--timer-ring)),
    #000 calc(100% - var(--timer-ring))
  );
  mask: radial-gradient(
    farthest-side,
    transparent calc(100% - var(--timer-ring)),
    #000 calc(100% - var(--timer-ring))
  );
  opacity: 0.86;
  transition:
    background 120ms linear,
    opacity 180ms ease;
  pointer-events: none;
}

button {
  border: none;
  border-radius: 8px;
  background: var(--button-color);
  color: var(--button-text);
  font-weight: 800;
  font-size: 16px;
  padding: 12px 32px;
}

button:hover {
  background: var(--button-hover);
}

button:active {
  transform: none;
}

button:focus-visible {
  outline: 2px solid rgba(187, 210, 255, 0.95);
  outline-offset: 2px;
}

.overlay {
  position: absolute;
  inset: 0;
  background: var(--overlay-backdrop);
  display: grid;
  place-items: center;
  padding: 16px 12px;
}

.overlay.hidden {
  display: none;
}

.hidden {
  display: none !important;
}

.overlay-card {
  width: min(370px, 100%);
  background: var(--modal-panel);
  color: var(--modal-ink);
  padding: 18px 14px 16px;
  text-align: center;
  border: none;
  border-radius: 0;
  box-shadow: none;
  display: grid;
  gap: 8px;
}

.overlay-card h2 {
  margin: 0 0 5px 0;
  font-size: 18px;
  line-height: 1.2;
  font-weight: 620;
}

.overlay-card h2:empty {
  display: none;
}

.overlay-card .overlay-description {
  margin: 0 2px 6px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.9);
  line-height: 1.35;
}

.overlay-card .overlay-score {
  margin: 0;
  font-size: 16px;
  font-weight: 550;
  color: rgba(233, 241, 255, 0.97);
}

.overlay-card button {
  margin-top: 6px;
  justify-self: center;
}

footer {
  text-align: center;
  margin-top: 0.25rem;
}

footer p {
  font-size: 0.7rem;
  font-weight: 300;
  color: var(--sand);
}

footer a {
  color: var(--sand);
  text-decoration: underline;
  text-decoration-style: dotted;
  text-decoration-color: var(--sand);
  text-underline-offset: 2px;
  transition:
    color 0.2s,
    text-decoration-color 0.2s;
}

footer a:hover {
  color: var(--sand);
  text-decoration-style: solid;
  text-decoration-color: var(--sand);
}

@media (max-width: 540px) {
  #score-display {
    font-size: 24px;
  }
  #timer-display {
    --timer-size: 24px;
  }
}