:root {
  color-scheme: light;
  --ink: oklch(22% 0.035 176);
  --ink-soft: oklch(38% 0.045 176);
  --paper: oklch(97% 0.01 176);
  --paper-deep: oklch(91% 0.018 176);
  --teal: oklch(56% 0.125 176);
  --teal-dark: oklch(42% 0.105 176);
  --teal-deep: oklch(28% 0.07 176);
  --yellow: oklch(84% 0.16 88);
  --coral: oklch(66% 0.19 30);
  --blue: oklch(64% 0.14 244);
  --green: oklch(66% 0.13 152);
  --cream: oklch(94% 0.04 88);
  --well: oklch(82% 0.025 176);
  --success: oklch(64% 0.14 150);
  --danger: oklch(58% 0.21 28);
  --focus: oklch(54% 0.18 252);
  --station-bg: var(--yellow);
  --key-ink: oklch(25% 0.03 176);
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4rem;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-snap: cubic-bezier(0.16, 1, 0.3, 1);
  --z-board-piece: 2;
  --z-screw: 3;
  --z-station: 15;
  --z-celebration: 20;
  --z-result: 30;
  --z-drag: 40;
  --z-skip: 50;
  --z-toast: 60;
  font-family: "Avenir Next", "PingFang SC", "Hiragino Sans GB", sans-serif;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --ink: oklch(93% 0.015 176);
  --ink-soft: oklch(74% 0.03 176);
  --paper: oklch(18% 0.022 176);
  --paper-deep: oklch(23% 0.03 176);
  --teal-dark: oklch(70% 0.09 176);
  --well: oklch(34% 0.03 176);
  --station-bg: oklch(31% 0.06 82);
}

* {
  box-sizing: border-box;
}

html {
  min-width: 20rem;
  background: var(--paper);
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  margin: 0;
  overflow-x: hidden;
  color: var(--ink);
  background:
    linear-gradient(90deg, color-mix(in oklch, var(--teal) 7%, transparent) 1px, transparent 1px) 0 0 / 3rem 3rem,
    linear-gradient(color-mix(in oklch, var(--teal) 7%, transparent) 1px, transparent 1px) 0 0 / 3rem 3rem,
    var(--paper);
  font-size: 1rem;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  padding:
    env(safe-area-inset-top)
    env(safe-area-inset-right)
    0
    env(safe-area-inset-left);
}

button,
summary,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  color: inherit;
  font: inherit;
}

button:focus {
  outline: none;
}

button:focus-visible,
summary:focus-visible,
a:focus-visible,
.share-challenge:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

button:disabled {
  cursor: not-allowed;
}

em {
  font-style: normal;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: var(--z-skip);
  padding: 0.75rem 1rem;
  clip-path: inset(50%);
  color: var(--cream);
  background: var(--teal-deep);
  opacity: 0;
  pointer-events: none;
  transform: translateY(-1rem);
  transition: opacity 150ms var(--ease-out), transform 180ms var(--ease-out);
}

.skip-link:focus {
  clip-path: none;
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.page-shell {
  width: min(100%, 100rem);
  margin-inline: auto;
}

.topbar {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: clamp(0.75rem, 2vw, 2rem);
  padding: clamp(0.6rem, 1.5vw, 1rem) clamp(1rem, 4vw, 4rem);
  border-bottom: 1px solid color-mix(in oklch, var(--ink) 18%, transparent);
  background: color-mix(in oklch, var(--paper) 94%, transparent);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  min-height: 3rem;
  color: var(--ink);
  text-decoration: none;
}

.brand strong {
  display: block;
  font-family: "DIN Alternate", "Avenir Next Condensed", "PingFang SC", sans-serif;
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  line-height: 1;
}

.brand small {
  display: block;
  margin-top: 0.3rem;
  color: var(--ink-soft);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.brand-cube {
  position: relative;
  display: grid;
  width: 2.4rem;
  height: 2.4rem;
  grid-template-columns: repeat(2, 1fr);
  grid-template-rows: repeat(2, 1fr);
  gap: 0.18rem;
  transform: rotate(-8deg);
}

.brand-cube i {
  display: block;
  background: var(--teal);
  border-radius: 0.2rem 0.55rem 0.2rem 0.2rem;
}

.brand-cube i:nth-child(2) {
  background: var(--yellow);
  border-radius: 0.55rem 0.2rem 0.2rem 0.2rem;
}

.brand-cube i:nth-child(3) {
  grid-column: 1 / -1;
  width: 48%;
  margin-left: 26%;
  background: var(--coral);
  border-radius: 0.2rem 0.2rem 0.55rem 0.55rem;
}

.mode-switcher {
  justify-self: center;
  display: flex;
  align-items: center;
  gap: 0.3rem;
  max-width: 100%;
  padding: 0.3rem;
  overflow-x: auto;
  border: 1px solid color-mix(in oklch, var(--ink) 20%, transparent);
  border-radius: 999px;
  background: var(--paper-deep);
}

.mode-button {
  min-height: 2.5rem;
  padding: 0.55rem 1rem;
  border: 0;
  border-radius: 999px;
  color: var(--ink-soft);
  background: transparent;
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 700;
  white-space: nowrap;
  transition: color 160ms var(--ease-out), background 160ms var(--ease-out), transform 120ms var(--ease-out);
}

.mode-button.is-active {
  color: var(--cream);
  background: var(--teal-deep);
}

.mode-button:active {
  transform: scale(0.97);
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2.75rem;
  min-height: 2.75rem;
  padding: 0.4rem;
  border: 1px solid color-mix(in oklch, var(--ink) 24%, transparent);
  border-radius: 0.6rem;
  color: var(--ink);
  background: transparent;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 800;
  transition: background 140ms var(--ease-out), transform 120ms var(--ease-out);
}

.icon-button:hover {
  background: color-mix(in oklch, var(--ink) 8%, transparent);
}

.icon-button:active {
  transform: scale(0.94);
}

#sound-button[aria-pressed="false"] {
  color: color-mix(in oklch, var(--ink) 42%, var(--paper));
  text-decoration: line-through;
}

.lang-button {
  font-size: 0.85rem;
}

.streak-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  min-height: 2.75rem;
  padding: 0.4rem 0.75rem;
  border: 1px solid color-mix(in oklch, var(--coral) 55%, transparent);
  border-radius: 999px;
  color: var(--ink);
  background: color-mix(in oklch, var(--coral) 12%, transparent);
  cursor: pointer;
  font-size: 0.85rem;
  transition: background 140ms var(--ease-out), transform 120ms var(--ease-out);
}

.streak-pill:hover {
  background: color-mix(in oklch, var(--coral) 22%, transparent);
}

.streak-pill strong {
  font-family: "DIN Alternate", "Avenir Next Condensed", sans-serif;
  font-variant-numeric: tabular-nums;
}

#main-content {
  padding: clamp(1rem, 2.5vw, 2rem) clamp(1rem, 4vw, 4rem) 2rem;
}

.share-challenge {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
  padding: 0.9rem 1rem;
  border: 1px solid color-mix(in oklch, var(--teal) 48%, var(--ink));
  border-left: 0.4rem solid var(--yellow);
  color: var(--cream);
  background: var(--teal-deep);
  box-shadow: 0 0.55rem 1.6rem oklch(20% 0.03 176 / 0.16);
}

.share-challenge[hidden] {
  display: none;
}

.share-challenge-copy > span {
  display: block;
  color: var(--yellow);
  font-size: 0.65rem;
  font-weight: 850;
  letter-spacing: 0.15em;
}

.share-challenge-copy strong {
  display: block;
  margin-top: 0.1rem;
  font-size: clamp(0.95rem, 2vw, 1.1rem);
}

.share-challenge-copy p {
  margin: 0.15rem 0 0;
  color: color-mix(in oklch, var(--cream) 78%, var(--teal));
  font-size: 0.8rem;
  text-wrap: pretty;
}

.share-challenge-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.5rem;
}

.share-challenge-actions button {
  min-height: 2.7rem;
  padding: 0.55rem 0.9rem;
  border: 1px solid color-mix(in oklch, var(--cream) 45%, transparent);
  color: var(--cream);
  background: transparent;
  cursor: pointer;
  font-size: 0.78rem;
  font-weight: 800;
}

#share-challenge-action {
  border-color: var(--yellow);
  color: var(--teal-deep);
  background: var(--yellow);
}

#share-challenge-action[hidden] {
  display: none;
}

.game-frame {
  container-type: inline-size;
}

.status-rail {
  display: grid;
  grid-template-columns: repeat(3, auto) minmax(13rem, 1fr);
  align-items: center;
  margin-bottom: -1px;
  border: 1px solid var(--teal-deep);
  background: var(--teal-deep);
  color: var(--cream);
}

.status-block,
.status-progress {
  min-height: 4.5rem;
  padding: 0.75rem clamp(1rem, 2vw, 2rem);
}

.status-block {
  display: flex;
  align-items: baseline;
  gap: 0.8rem;
  border-right: 1px solid color-mix(in oklch, var(--cream) 20%, transparent);
}

.status-block span,
.status-progress span {
  color: color-mix(in oklch, var(--cream) 72%, var(--teal));
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.status-block strong {
  font-family: "DIN Alternate", "Avenir Next Condensed", sans-serif;
  font-size: 1.45rem;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.06em;
}

.status-progress {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 0.9rem;
}

.status-progress strong {
  min-width: 2.75rem;
  text-align: right;
  font-family: "DIN Alternate", "Avenir Next Condensed", sans-serif;
  font-variant-numeric: tabular-nums;
}

.progress-track {
  height: 0.35rem;
  overflow: hidden;
  background: color-mix(in oklch, var(--cream) 18%, var(--teal-deep));
}

.progress-track i {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--yellow);
  transform-origin: left center;
  transform: scaleX(0);
  transition: transform 260ms var(--ease-out);
}

.machine-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.65fr) minmax(18rem, 0.75fr);
  align-items: stretch;
  border: 1px solid var(--teal-deep);
  background: var(--paper);
}

.console {
  display: grid;
  grid-template-columns: minmax(10rem, 0.55fr) minmax(22rem, 1fr);
  min-width: 0;
  padding: clamp(1rem, 2.5vw, 2.25rem);
  background:
    radial-gradient(circle at 15% 13%, color-mix(in oklch, var(--paper) 85%, transparent) 0 0.08rem, transparent 0.09rem) 0 0 / 0.8rem 0.8rem,
    var(--paper-deep);
}

.console-panel {
  display: flex;
  min-width: 0;
  flex-direction: column;
  padding: clamp(0.25rem, 1vw, 0.75rem) clamp(1rem, 2vw, 2rem) clamp(0.25rem, 1vw, 0.75rem) 0;
}

.prompt-screen {
  min-height: 14rem;
  padding: clamp(1rem, 2vw, 1.5rem);
  border: 0.45rem solid var(--teal-deep);
  border-radius: 0.5rem;
  color: oklch(85% 0.13 161);
  background: oklch(20% 0.05 175);
  box-shadow: inset 0 0 0 1px color-mix(in oklch, var(--cream) 15%, transparent);
}

.screen-topline {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.1rem;
  color: oklch(74% 0.1 161);
  font-family: "DIN Alternate", "Avenir Next Condensed", sans-serif;
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.14em;
}

#game-message {
  min-height: 3.5rem;
  margin: 0;
  color: oklch(94% 0.055 88);
  font-size: clamp(0.95rem, 1.2vw, 1.08rem);
  font-weight: 650;
  line-height: 1.65;
}

.piece-ledger {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 1rem;
}

.ledger-token {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  min-height: 1.8rem;
  padding: 0.3rem 0.5rem;
  border: 1px solid color-mix(in oklch, var(--cream) 22%, transparent);
  color: color-mix(in oklch, var(--cream) 72%, var(--teal));
  font-size: 0.68rem;
  font-weight: 800;
}

.ledger-token::before {
  content: "";
  width: 0.55rem;
  height: 0.55rem;
  background: var(--piece-color);
  transform: rotate(45deg);
}

.ledger-token.is-placed {
  color: oklch(82% 0.1 153);
  border-color: color-mix(in oklch, var(--green) 44%, transparent);
}

.ledger-token.is-placed::after {
  content: "✓";
}

.console-actions {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 0.65rem;
  margin-top: 1.3rem;
}

.machine-key {
  min-height: 4.2rem;
  padding: 0.55rem;
  border: 0;
  border-bottom: 0.35rem solid oklch(62% 0.03 176);
  border-radius: 0.7rem;
  color: var(--key-ink);
  background: var(--cream);
  cursor: pointer;
  font-size: 0.72rem;
  font-weight: 800;
  transition: transform 100ms var(--ease-out), filter 140ms var(--ease-out);
}

.machine-key span {
  display: block;
  margin-bottom: 0.15rem;
  font-size: 1.05rem;
  line-height: 1;
}

.machine-key.key-red {
  color: var(--cream);
  background: var(--coral);
  border-bottom-color: color-mix(in oklch, var(--coral) 65%, oklch(20% 0 0));
}

.machine-key:active {
  transform: translateY(0.25rem);
  border-bottom-width: 0.1rem;
}

.machine-key:disabled {
  filter: saturate(0.4) opacity(0.6);
}

@keyframes help-nudge {
  0%, 100% { box-shadow: 0 0 0 0 color-mix(in oklch, var(--yellow) 0%, transparent); }
  50% { box-shadow: 0 0 0 0.28rem color-mix(in oklch, var(--yellow) 48%, transparent); }
}

.machine-key.is-stall-suggested:not(:disabled) {
  outline: 0.16rem solid color-mix(in oklch, var(--yellow) 72%, var(--ink));
  outline-offset: 0.16rem;
  animation: help-nudge 1.8s ease-in-out infinite;
}

.mode-note {
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
  margin-top: auto;
  padding-top: 1.5rem;
}

.mode-note p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.78rem;
  line-height: 1.65;
}

.pulse-dot {
  flex: 0 0 auto;
  width: 0.6rem;
  height: 0.6rem;
  margin-top: 0.28rem;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 0.3rem color-mix(in oklch, var(--green) 18%, transparent);
}

.board-stage {
  position: relative;
  align-self: center;
  width: 100%;
  max-width: 40rem;
  padding: clamp(1rem, 3vw, 2rem);
  border: 1px solid color-mix(in oklch, var(--teal-deep) 26%, transparent);
  border-radius: clamp(1.2rem, 3vw, 2.4rem);
  background: color-mix(in oklch, var(--paper) 88%, var(--teal));
  box-shadow:
    0 1.3rem 3rem color-mix(in oklch, var(--teal-deep) 15%, transparent),
    inset 0 0 0 0.45rem color-mix(in oklch, var(--paper) 75%, var(--teal));
}

.screw {
  position: absolute;
  z-index: var(--z-screw);
  width: 0.55rem;
  height: 0.55rem;
  border: 1px solid color-mix(in oklch, var(--teal-deep) 40%, transparent);
  border-radius: 50%;
  background: var(--paper-deep);
}

.screw::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 14%;
  width: 72%;
  height: 1px;
  background: color-mix(in oklch, var(--teal-deep) 40%, transparent);
  transform: rotate(-25deg);
}

.screw-a { top: 0.72rem; left: 0.9rem; }
.screw-b { top: 0.72rem; right: 0.9rem; }
.screw-c { bottom: 0.72rem; left: 0.9rem; }
.screw-d { right: 0.9rem; bottom: 0.72rem; }

.game-board {
  position: relative;
  display: grid;
  aspect-ratio: 1;
  grid-template-columns: repeat(var(--board-size, 8), minmax(0, 1fr));
  grid-template-rows: repeat(var(--board-size, 8), minmax(0, 1fr));
  gap: clamp(0.18rem, 0.55vw, 0.36rem);
  width: 100%;
  padding: clamp(0.55rem, 1.4vw, 0.9rem);
  border: 0.32rem solid var(--teal-deep);
  border-radius: 1rem;
  background: oklch(29% 0.045 176);
  box-shadow:
    inset 0 0.4rem 1.2rem oklch(20% 0.03 176 / 0.55),
    0 0 0 0.28rem color-mix(in oklch, var(--teal-deep) 18%, transparent);
  touch-action: none;
  user-select: none;
}

.board-cell {
  position: relative;
  min-width: 0;
  min-height: 0;
  padding: 0;
  overflow: visible;
  border: 0;
  border-radius: 24%;
  background: color-mix(in oklch, var(--teal-deep) 76%, oklch(82% 0.025 176));
  cursor: crosshair;
  transition: transform 120ms var(--ease-out), background 140ms var(--ease-out), filter 140ms var(--ease-out);
}

.board-cell::before {
  content: "";
  position: absolute;
  inset: 23%;
  border: 1px solid oklch(97% 0.01 176 / 0.13);
  border-radius: 50%;
  background: oklch(18% 0.025 176);
  box-shadow: inset 0 0.15rem 0.3rem oklch(15% 0.02 176 / 0.7);
}

.board-cell.is-target {
  background: oklch(48% 0.06 176);
}

.board-cell.is-target::before {
  border-color: oklch(97% 0.05 90);
  background: oklch(95% 0.1 93);
  box-shadow:
    0 0 0.95rem color-mix(in oklch, var(--yellow) 85%, transparent),
    0 0 0.3rem color-mix(in oklch, var(--yellow) 60%, transparent),
    inset 0 0 0.22rem var(--cream);
}

.board-cell.is-filled {
  z-index: var(--z-board-piece);
  background: var(--piece-color);
  box-shadow:
    inset 0.08rem 0.08rem 0 color-mix(in oklch, var(--cream) 35%, transparent),
    inset -0.12rem -0.14rem 0 oklch(20% 0.02 176 / 0.17);
  cursor: grab;
}

.board-cell.is-filled::before {
  border-color: color-mix(in oklch, var(--cream) 48%, transparent);
  background: color-mix(in oklch, oklch(97% 0.01 176) 82%, var(--piece-color));
  box-shadow: inset 0 0.12rem 0.2rem oklch(20% 0.02 176 / 0.3);
}

.board-cell.is-preplaced {
  cursor: not-allowed;
  outline: 2px solid color-mix(in oklch, var(--cream) 72%, var(--teal-deep));
  outline-offset: -3px;
}

.board-cell.is-preplaced::after {
  content: "◆";
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: color-mix(in oklch, var(--teal-deep) 78%, var(--cream));
  font-size: 0.42em;
  text-shadow: 0 1px 0 color-mix(in oklch, var(--cream) 55%, transparent);
}

.board-cell.is-pinned {
  background: color-mix(in oklch, var(--yellow) 40%, var(--teal-deep));
  cursor: not-allowed;
}

.board-cell.is-pinned::before {
  border-color: color-mix(in oklch, var(--yellow) 75%, var(--cream));
  background: color-mix(in oklch, var(--yellow) 80%, var(--cream));
  box-shadow:
    0 0 0.55rem color-mix(in oklch, var(--yellow) 60%, transparent),
    inset 0 0 0.18rem var(--cream);
}

.board-cell.is-pinned::after {
  content: "✕";
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: color-mix(in oklch, var(--teal-deep) 80%, var(--yellow));
  font-size: 0.6em;
  font-weight: 800;
}

.board-cell.is-selected {
  filter: saturate(1.12) brightness(1.08);
  animation: selected-piece 900ms ease-in-out infinite alternate;
}

.board-cell.is-hint:not(.is-filled)::after {
  content: "";
  position: absolute;
  inset: 9%;
  border: 2px dashed color-mix(in oklch, var(--green) 82%, var(--cream));
  border-radius: 28%;
  animation: hint-pulse 1.1s ease-in-out infinite alternate;
}

.board-cell.is-preview-valid:not(.is-filled) {
  background: color-mix(in oklch, var(--green) 44%, var(--teal-deep));
  transform: scale(0.92);
}

.board-cell.is-preview-invalid:not(.is-filled) {
  background: color-mix(in oklch, var(--danger) 58%, var(--teal-deep));
  transform: scale(0.92);
}

.board-cell.is-just-placed {
  animation: cell-pop 420ms var(--ease-snap) var(--pop-delay, 0ms) backwards;
}

.board-cell.is-clear-wave {
  animation: clear-wave 720ms var(--ease-out) var(--pop-delay, 0ms) both;
}

.game-board.is-error {
  animation: board-error 260ms var(--ease-out);
}

.game-board.is-cleared {
  animation: board-clear 600ms var(--ease-out);
}

.board-instruction {
  margin: 1rem 0 0;
  color: var(--ink-soft);
  text-align: center;
  font-size: 0.75rem;
  font-weight: 650;
}

.result-banner {
  position: absolute;
  z-index: var(--z-result);
  right: clamp(0.8rem, 2vw, 1.5rem);
  bottom: clamp(0.8rem, 2vw, 1.5rem);
  left: clamp(0.8rem, 2vw, 1.5rem);
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.1rem;
  color: var(--cream);
  background: var(--teal-deep);
  box-shadow: 0 0.8rem 2.2rem oklch(20% 0.03 176 / 0.28);
  animation: result-in 420ms var(--ease-out);
}

.result-banner[hidden] {
  display: none;
}

.result-banner.is-over {
  background: color-mix(in oklch, var(--coral) 58%, var(--teal-deep));
}

.result-banner .result-info > span:first-child {
  display: block;
  margin-bottom: 0.1rem;
  color: color-mix(in oklch, var(--cream) 65%, var(--yellow));
  font-size: 0.62rem;
  font-weight: 800;
  letter-spacing: 0.16em;
}

.result-banner strong {
  display: block;
  font-size: 1.1rem;
}

.result-banner p {
  margin: 0.15rem 0 0;
  color: color-mix(in oklch, var(--cream) 75%, var(--teal));
  font-size: 0.75rem;
}

.result-banner .result-detail {
  display: block;
  margin-top: 0.15rem;
  color: color-mix(in oklch, var(--cream) 88%, var(--yellow));
  font-size: 0.7rem;
  font-weight: 750;
  text-wrap: pretty;
}

.result-banner .result-detail[hidden] {
  display: none;
}

.result-banner .result-mastery {
  color: var(--yellow);
}

.result-banner .result-best {
  color: color-mix(in oklch, var(--cream) 90%, var(--teal));
}

.result-stars {
  display: inline-flex;
  gap: 0.3rem;
  margin-top: 0.35rem;
}

.result-stars[hidden] {
  display: none;
}

.star {
  width: 1.05rem;
  height: 1.05rem;
  clip-path: polygon(50% 0%, 61% 35%, 98% 35%, 68% 57%, 79% 91%, 50% 70%, 21% 91%, 32% 57%, 2% 35%, 39% 35%);
  background: color-mix(in oklch, var(--cream) 26%, transparent);
}

.star.is-earned {
  background: var(--yellow);
  animation: star-pop 460ms var(--ease-snap) backwards;
}

.star.is-earned:nth-child(2) { animation-delay: 140ms; }
.star.is-earned:nth-child(3) { animation-delay: 280ms; }

.result-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.result-banner .result-buttons button {
  min-height: 2.8rem;
  padding: 0.6rem 1rem;
  border: 0;
  cursor: pointer;
  font-size: 0.8rem;
  font-weight: 850;
}

#result-action {
  color: var(--teal-deep);
  background: var(--yellow);
}

#share-button {
  color: var(--cream);
  border: 1px solid color-mix(in oklch, var(--cream) 55%, transparent) !important;
  background: transparent;
}

#share-button[hidden] {
  display: none;
}

.celebration {
  position: absolute;
  z-index: var(--z-celebration);
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.confetti-bit {
  position: absolute;
  top: 18%;
  left: 50%;
  width: 0.48rem;
  height: 0.8rem;
  background: var(--confetti-color);
  opacity: 0;
  transform: translate(-50%, -50%) rotate(var(--rotation));
  animation: confetti-fall 1.15s var(--ease-out) var(--delay) forwards;
}

.piece-station {
  min-width: 0;
  padding: clamp(1.25rem, 3vw, 2.5rem);
  border-left: 1px solid var(--teal-deep);
  background: var(--station-bg);
}

.station-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.station-heading h2 {
  margin: 0;
  font-size: clamp(1.65rem, 2.7vw, 2.4rem);
  letter-spacing: -0.055em;
  line-height: 1;
}

.station-heading > p {
  max-width: 8rem;
  margin: 0;
  color: color-mix(in oklch, var(--ink) 78%, var(--station-bg));
  text-align: right;
  font-size: 0.72rem;
  font-weight: 800;
}

.piece-tray {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  min-height: 17rem;
}

.piece-card {
  position: relative;
  display: grid;
  min-height: 8rem;
  place-items: center;
  padding: 1rem 0.6rem 1.6rem;
  overflow: hidden;
  border: 1px solid oklch(25% 0.03 176 / 0.26);
  border-radius: 0;
  color: var(--key-ink);
  background: color-mix(in oklch, var(--cream) 83%, var(--yellow));
  cursor: grab;
  touch-action: none;
  transition: transform 180ms var(--ease-out), background 180ms var(--ease-out), box-shadow 180ms var(--ease-out);
}

.piece-card::before {
  content: "";
  position: absolute;
  top: 0.55rem;
  right: 0.55rem;
  width: 0.45rem;
  height: 0.45rem;
  border-radius: 50%;
  background: oklch(25% 0.03 176 / 0.14);
}

.piece-card:hover {
  transform: translateY(-0.18rem);
  box-shadow: 0 0.5rem 0 color-mix(in oklch, var(--ink) 16%, var(--station-bg));
}

.piece-card:active {
  cursor: grabbing;
}

.piece-card.is-selected {
  color: var(--cream);
  background: var(--teal-deep);
  box-shadow: 0 0.45rem 0 color-mix(in oklch, var(--teal-deep) 70%, oklch(20% 0 0));
}

.piece-card.is-placed:not(.is-selected) {
  background: color-mix(in oklch, oklch(91% 0.018 176) 70%, var(--yellow));
}

.piece-card.is-placed:not(.is-selected) .mini-grid {
  filter: saturate(0.45);
  opacity: 0.62;
}

.piece-card-name {
  position: absolute;
  right: 0.65rem;
  bottom: 0.45rem;
  left: 0.65rem;
  display: flex;
  justify-content: space-between;
  gap: 0.5rem;
  font-size: 0.64rem;
  font-weight: 800;
}

.piece-card-name span:last-child {
  opacity: 0.62;
}

.mini-grid {
  display: grid;
  grid-template-columns: repeat(var(--piece-cols), 1.05rem);
  grid-template-rows: repeat(var(--piece-rows), 1.05rem);
  gap: 0.12rem;
  pointer-events: none;
}

.mini-cell {
  position: relative;
  width: 1.05rem;
  height: 1.05rem;
  border-radius: 0.18rem;
  background: var(--piece-color);
  box-shadow:
    inset 0.08rem 0.08rem 0 color-mix(in oklch, var(--cream) 30%, transparent),
    inset -0.1rem -0.12rem 0 oklch(20% 0.02 176 / 0.17);
}

.mini-cell::after {
  content: "";
  position: absolute;
  inset: 31%;
  border-radius: 50%;
  background: color-mix(in oklch, oklch(97% 0.01 176) 76%, var(--piece-color));
  box-shadow: inset 0 0.08rem 0.1rem oklch(20% 0.02 176 / 0.24);
}

.mini-cell.is-empty {
  visibility: hidden;
}

.transform-controls {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.5rem;
  margin-top: 1rem;
}

.transform-controls button {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 0.5rem;
  min-height: 3rem;
  padding: 0.6rem 0.75rem;
  border: 1px solid color-mix(in oklch, var(--ink) 38%, transparent);
  border-radius: 0;
  background: transparent;
  cursor: pointer;
  font-size: 0.75rem;
  font-weight: 800;
  transition: color 140ms var(--ease-out), background 140ms var(--ease-out), transform 120ms var(--ease-out);
}

.transform-controls button:not(:disabled):hover {
  color: var(--cream);
  background: var(--teal-deep);
}

.transform-controls button:not(:disabled):active {
  transform: scale(0.98);
}

.transform-controls button:disabled {
  color: color-mix(in oklch, var(--ink) 42%, var(--station-bg));
  border-color: color-mix(in oklch, var(--ink) 18%, transparent);
}

.transform-controls button > span {
  width: 1.2rem;
  font-size: 1rem;
}

kbd {
  margin-left: auto;
  padding: 0.08rem 0.28rem;
  border: 1px solid currentColor;
  font-family: inherit;
  font-size: 0.58rem;
  opacity: 0.55;
}

.coach-strip {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.45rem;
  margin-top: 1.4rem;
  padding-top: 1rem;
  border-top: 1px solid color-mix(in oklch, var(--ink) 26%, transparent);
  color: color-mix(in oklch, var(--ink) 78%, var(--station-bg));
  font-size: 0.62rem;
  font-weight: 800;
}

.coach-strip i {
  flex: 1;
  height: 1px;
  background: color-mix(in oklch, var(--ink) 28%, transparent);
}

.drag-ghost {
  position: fixed;
  z-index: var(--z-drag);
  display: grid;
  place-items: center;
  width: 6.5rem;
  height: 6.5rem;
  border: 1px solid oklch(25% 0.03 176 / 0.2);
  background: color-mix(in oklch, var(--cream) 90%, transparent);
  box-shadow: 0 1rem 2rem oklch(20% 0.03 176 / 0.25);
  pointer-events: none;
  transform: translate(-50%, -50%) rotate(-3deg);
}

.drag-ghost .mini-grid {
  transform: scale(1.35);
}

body.is-dragging,
body.is-dragging * {
  cursor: grabbing !important;
}

.help-panel {
  margin-top: 1.5rem;
  border-top: 1px solid color-mix(in oklch, var(--ink) 22%, transparent);
  border-bottom: 1px solid color-mix(in oklch, var(--ink) 22%, transparent);
}

.help-panel summary {
  min-height: 3.5rem;
  padding: 1rem 0;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 800;
}

.help-content {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(1rem, 3vw, 3rem);
  padding: 0.5rem 0 1.5rem;
}

.help-content p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.82rem;
  line-height: 1.7;
}

.page-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.5rem clamp(1rem, 4vw, 4rem) calc(2rem + env(safe-area-inset-bottom));
  color: color-mix(in oklch, var(--ink) 58%, var(--paper));
  font-size: 0.7rem;
  font-weight: 650;
}

.page-footer p {
  margin: 0;
}

/* --- Content pages (guide / about / privacy) --- */

.content-topbar {
  grid-template-columns: auto 1fr;
}

.play-link {
  justify-self: end;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  min-height: 2.75rem;
  padding: 0.5rem 1rem;
  border-radius: 0.6rem;
  color: var(--cream);
  background: var(--teal-deep);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 800;
  transition: transform 120ms var(--ease-out), filter 140ms var(--ease-out);
}

.play-link:hover {
  filter: brightness(1.15);
}

.play-link:active {
  transform: scale(0.96);
}

.content-page {
  max-width: 46rem;
  margin-inline: auto;
  padding: clamp(1.5rem, 4vw, 3rem) 1rem 3rem;
}

.content-page h1 {
  margin: 0 0 1rem;
  font-size: clamp(1.9rem, 4vw, 2.7rem);
  letter-spacing: -0.03em;
  line-height: 1.1;
}

.content-page .lede {
  color: var(--ink-soft);
  font-size: 1.08rem;
  line-height: 1.8;
}

.content-page h2 {
  margin: 2.4rem 0 0.75rem;
  font-size: 1.3rem;
  letter-spacing: -0.02em;
}

.content-page p,
.content-page li,
.content-page dd {
  line-height: 1.75;
}

.content-page ul,
.content-page ol {
  padding-left: 1.4rem;
}

.content-page li {
  margin-bottom: 0.55rem;
}

.content-page a {
  color: var(--teal-dark);
  font-weight: 650;
}

.content-page kbd {
  margin-left: 0;
  opacity: 0.8;
}

.policy-date {
  color: var(--ink-soft);
  font-size: 0.8rem;
  font-weight: 700;
}

.faq dt {
  margin-top: 1.1rem;
  font-weight: 800;
}

.faq dd {
  margin: 0.3rem 0 0;
  color: var(--ink-soft);
}

.content-cta {
  margin-top: 2.5rem;
}

.content-cta a {
  display: inline-block;
  padding: 0.85rem 1.5rem;
  color: var(--teal-deep);
  background: var(--yellow);
  text-decoration: none;
  font-weight: 850;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-nav a {
  color: inherit;
  font-weight: 700;
}

.footer-nav a[aria-current="page"] {
  color: var(--teal-dark);
}

/* --- Level map dialog --- */

.map-dialog {
  width: min(42rem, 92vw);
  max-height: 84vh;
  padding: clamp(1.25rem, 3vw, 2rem);
  border: 1px solid color-mix(in oklch, var(--ink) 25%, transparent);
  border-radius: 1rem;
  color: var(--ink);
  background: var(--paper);
  box-shadow: 0 1.5rem 4rem oklch(15% 0.03 176 / 0.35);
}

.map-dialog::backdrop {
  background: oklch(15% 0.03 176 / 0.55);
}

.map-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.map-head h2 {
  margin: 0;
  font-size: 1.5rem;
  letter-spacing: -0.03em;
}

.map-intro {
  margin: 0.4rem 0 1.25rem;
  color: var(--ink-soft);
  font-size: 0.85rem;
}

.chapter-nav {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
  padding: 0.5rem 0.6rem;
  border: 1px solid color-mix(in oklch, var(--ink) 16%, transparent);
  border-radius: 0.8rem;
  background: var(--paper-deep);
}

.chapter-title {
  text-align: center;
}

.chapter-title strong {
  display: block;
  font-size: 0.95rem;
  letter-spacing: -0.01em;
}

.chapter-title small {
  color: var(--ink-soft);
  font-size: 0.7rem;
}

.chapter-nav .icon-button:disabled {
  opacity: 0.35;
}

.level-map-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(4.1rem, 1fr));
  gap: 0.5rem;
}

.map-level {
  display: grid;
  gap: 0.15rem;
  justify-items: center;
  min-height: 4.6rem;
  padding: 0.55rem 0.25rem 0.4rem;
  border: 1px solid color-mix(in oklch, var(--ink) 22%, transparent);
  border-radius: 0.7rem;
  background: var(--paper-deep);
  cursor: pointer;
  font-size: 0.8rem;
  transition: transform 140ms var(--ease-out), background 140ms var(--ease-out);
}

.map-level:not(:disabled):hover {
  transform: translateY(-0.15rem);
  background: color-mix(in oklch, var(--yellow) 24%, var(--paper-deep));
}

.map-level strong {
  font-family: "DIN Alternate", "Avenir Next Condensed", sans-serif;
  font-variant-numeric: tabular-nums;
}

.map-level small {
  min-height: 1em;
  color: color-mix(in oklch, var(--yellow) 70%, var(--ink));
  font-size: 0.62rem;
  letter-spacing: 0.08em;
}

.map-bulb {
  width: 0.85rem;
  height: 0.85rem;
  border: 1px solid color-mix(in oklch, var(--ink) 30%, transparent);
  border-radius: 50%;
  background: color-mix(in oklch, var(--ink) 10%, var(--paper-deep));
}

.map-level.is-cleared .map-bulb {
  border-color: color-mix(in oklch, var(--yellow) 80%, var(--ink));
  background: var(--yellow);
  box-shadow: 0 0 0.55rem color-mix(in oklch, var(--yellow) 75%, transparent);
}

.map-level.is-mastered {
  border-color: color-mix(in oklch, var(--yellow) 75%, var(--teal-deep));
  background: color-mix(in oklch, var(--yellow) 14%, var(--paper-deep));
}

.map-level.is-mastered small {
  color: color-mix(in oklch, var(--yellow) 85%, var(--teal-deep));
}

.map-level.is-current {
  border-color: var(--teal);
  box-shadow: 0 0 0 2px color-mix(in oklch, var(--teal) 45%, transparent);
}

.map-level.is-current .map-bulb {
  animation: bulb-breathe 1.4s ease-in-out infinite alternate;
}

.map-level.is-locked {
  opacity: 0.45;
  cursor: not-allowed;
}

.map-subtitle {
  margin: 1.75rem 0 0.75rem;
  font-size: 1.05rem;
}

.achievement-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
  gap: 0.6rem;
}

.achievement {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 0.65rem 0.8rem;
  border: 1px solid color-mix(in oklch, var(--ink) 18%, transparent);
  border-radius: 0.7rem;
  opacity: 0.45;
  filter: saturate(0.2);
}

.achievement.is-unlocked {
  opacity: 1;
  filter: none;
  border-color: color-mix(in oklch, var(--yellow) 60%, var(--ink));
  background: color-mix(in oklch, var(--yellow) 14%, var(--paper));
}

.achievement-icon {
  display: grid;
  place-items: center;
  width: 2.2rem;
  height: 2.2rem;
  flex: 0 0 auto;
  border-radius: 50%;
  background: color-mix(in oklch, var(--yellow) 35%, var(--paper-deep));
  font-size: 1rem;
}

.achievement-body strong {
  display: block;
  font-size: 0.82rem;
}

.achievement-body small {
  color: var(--ink-soft);
  font-size: 0.72rem;
}

/* --- Toasts --- */

.toast-stack {
  position: fixed;
  top: var(--toast-top, calc(5rem + env(safe-area-inset-top)));
  right: calc(1rem + env(safe-area-inset-right));
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  pointer-events: none;
}

.toast {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  max-width: 20rem;
  padding: 0.7rem 0.95rem;
  border-radius: 0.7rem;
  color: var(--cream);
  background: var(--teal-deep);
  box-shadow: 0 0.7rem 1.8rem oklch(15% 0.03 176 / 0.35);
  animation: toast-in 320ms var(--ease-snap);
  border: 0;
  cursor: pointer;
  pointer-events: auto;
  text-align: left;
}

.toast.is-leaving {
  animation: toast-out 420ms var(--ease-out) forwards;
}

.toast-icon {
  display: grid;
  place-items: center;
  width: 2rem;
  height: 2rem;
  flex: 0 0 auto;
  border-radius: 50%;
  background: color-mix(in oklch, var(--yellow) 80%, var(--teal-deep));
  color: var(--teal-deep);
  font-size: 0.95rem;
}

.toast-body strong {
  display: block;
  font-size: 0.82rem;
}

.toast-body small {
  color: color-mix(in oklch, var(--cream) 75%, var(--teal));
  font-size: 0.7rem;
}

/* --- Animations --- */

@keyframes selected-piece {
  to { filter: brightness(1.16) saturate(1.16); }
}

@keyframes hint-pulse {
  to { opacity: 0.38; transform: scale(0.82); }
}

@keyframes cell-pop {
  0% { transform: scale(0.55); filter: brightness(2); }
  55% { transform: scale(1.12); filter: brightness(1.35); }
  100% { transform: scale(1); filter: none; }
}

@keyframes clear-wave {
  0% { transform: scale(1); }
  35% { transform: scale(1.14); filter: brightness(1.9) saturate(1.3); }
  100% { transform: scale(1); filter: none; }
}

@keyframes star-pop {
  0% { transform: scale(0); }
  60% { transform: scale(1.35) rotate(8deg); }
  100% { transform: scale(1); }
}

@keyframes bulb-breathe {
  from { box-shadow: 0 0 0.2rem color-mix(in oklch, var(--yellow) 40%, transparent); background: color-mix(in oklch, var(--yellow) 45%, var(--paper-deep)); }
  to { box-shadow: 0 0 0.7rem color-mix(in oklch, var(--yellow) 85%, transparent); background: var(--yellow); }
}

@keyframes toast-in {
  from { opacity: 0; transform: translateX(1.5rem); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes toast-out {
  to { opacity: 0; transform: translateX(1.5rem); }
}

@keyframes board-error {
  25% { transform: translateX(-0.35rem); }
  60% { transform: translateX(0.3rem); }
  100% { transform: translateX(0); }
}

@keyframes board-clear {
  45% { filter: brightness(1.35) saturate(1.15); transform: scale(1.012); }
  100% { filter: none; transform: scale(1); }
}

@keyframes result-in {
  from { opacity: 0; transform: translateY(1.5rem); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes confetti-fall {
  0% { opacity: 0; transform: translate(-50%, -50%) rotate(var(--rotation)); }
  10% { opacity: 1; }
  100% {
    opacity: 0;
    transform: translate(calc(-50% + var(--travel-x)), 18rem) rotate(calc(var(--rotation) + 540deg));
  }
}

/* --- Responsive --- */

@container (max-width: 73rem) {
  .machine-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .piece-station {
    border-top: 1px solid var(--teal-deep);
    border-left: 0;
  }

  .piece-tray {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    min-height: auto;
  }

  .transform-controls {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (max-width: 62rem) {
  .topbar {
    grid-template-columns: 1fr auto;
  }

  .mode-switcher {
    grid-column: 1 / -1;
    grid-row: 2;
    justify-self: stretch;
    justify-content: safe center;
  }

  .status-rail {
    grid-template-columns: repeat(3, 1fr);
  }

  .status-progress {
    grid-column: 1 / -1;
    border-top: 1px solid color-mix(in oklch, var(--cream) 20%, transparent);
  }

  .console {
    grid-template-columns: minmax(9rem, 0.62fr) minmax(20rem, 1fr);
  }
}

@media (max-width: 46rem) {
  #main-content {
    padding-top: 0.9rem;
  }

  .share-challenge {
    grid-template-columns: 1fr;
  }

  .share-challenge-actions {
    justify-content: stretch;
  }

  .share-challenge-actions button {
    flex: 1;
  }

  .console {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
  }

  .board-stage {
    order: -1;
  }

  .console-panel {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 0.8rem;
    padding: 0;
  }

  .prompt-screen {
    min-height: 0;
  }

  .console-actions {
    grid-template-columns: 1fr;
    margin-top: 0;
  }

  .machine-key {
    min-width: 4.8rem;
    min-height: 3.5rem;
  }

  .mode-note {
    grid-column: 1 / -1;
    margin-top: 0;
    padding-top: 0;
  }

  /* Sticky bottom tray: board and blocks share the screen. */
  .piece-station {
    position: sticky;
    bottom: 0;
    z-index: var(--z-station);
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    align-items: center;
    gap: 0.6rem;
    padding: 0.6rem 0.75rem calc(0.6rem + env(safe-area-inset-bottom));
    border-top: 2px solid var(--teal-deep);
    box-shadow: 0 -0.6rem 1.6rem oklch(20% 0.03 176 / 0.22);
  }

  .station-heading,
  .coach-strip {
    display: none;
  }

  .piece-tray {
    display: flex;
    gap: 0.5rem;
    min-height: 0;
    overflow-x: auto;
    padding-bottom: 0.15rem;
    scrollbar-width: thin;
  }

  .piece-card {
    flex: 1 0 3.75rem;
    width: auto;
    max-width: 5.4rem;
    min-height: 5.35rem;
    padding: 0.5rem 0.4rem 1.35rem;
    touch-action: pan-x;
  }

  .piece-card .mini-grid {
    grid-template-columns: repeat(var(--piece-cols), 0.72rem);
    grid-template-rows: repeat(var(--piece-rows), 0.72rem);
  }

  .piece-card .mini-cell {
    width: 0.72rem;
    height: 0.72rem;
  }

  .piece-card-name {
    right: 0.45rem;
    bottom: 0.35rem;
    left: 0.45rem;
    font-size: 0.56rem;
  }

  .transform-controls {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0.4rem;
    margin-top: 0;
  }

  .transform-controls button {
    min-height: 2.6rem;
    padding: 0.45rem 0.55rem;
    font-size: 0.66rem;
  }

  .transform-controls kbd {
    display: none;
  }

  .help-content {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }

  /* 10×10 chapters: shed chrome so each cell keeps a usable touch size. */
  body[data-board="10"] .board-stage {
    padding: 0.5rem;
    border-radius: 0.9rem;
  }

  body[data-board="10"] .game-board {
    gap: 0.14rem;
    padding: 0.35rem;
  }
}

@media (max-width: 34rem) {
  .topbar {
    padding-inline: 0.7rem;
    gap: 0.5rem;
  }

  .brand {
    min-height: 2.5rem;
    gap: 0.5rem;
  }

  .brand small {
    display: none;
  }

  .brand-cube {
    width: 2rem;
    height: 2rem;
  }

  .topbar-actions {
    gap: 0.2rem;
  }

  .icon-button {
    min-width: 2.25rem;
    min-height: 2.25rem;
    padding: 0.3rem;
  }

  .streak-pill {
    min-height: 2.25rem;
    padding-inline: 0.5rem;
    font-size: 0.78rem;
  }

  .mode-switcher {
    gap: 0.1rem;
  }

  .mode-button {
    flex: 1;
    min-height: 2.75rem;
    padding-inline: 0.45rem;
    font-size: 0.75rem;
  }

  #main-content {
    padding-inline: 0.75rem;
  }

  .status-block,
  .status-progress {
    min-height: 3.8rem;
    padding-inline: 0.65rem;
  }

  .status-block {
    display: grid;
    gap: 0.1rem;
  }

  .status-block strong {
    font-size: 1.15rem;
  }

  .console {
    padding: 0.75rem;
  }

  .console-panel {
    grid-template-columns: 1fr;
  }

  .console-actions {
    grid-template-columns: repeat(3, 1fr);
  }

  .machine-key {
    min-width: 0;
  }

  .board-stage {
    padding: 1rem;
    border-radius: 1.2rem;
  }

  .game-board {
    gap: 0.18rem;
    padding: 0.45rem;
  }

  .result-banner {
    grid-template-columns: 1fr;
  }

  .result-banner .result-buttons button {
    flex: 1;
  }

  .page-footer {
    flex-direction: column;
    padding-inline: 1rem;
  }
}

@media (max-width: 24rem) {
  .topbar {
    grid-template-columns: minmax(0, 1fr);
    padding-inline: 0.7rem;
  }

  .brand {
    grid-column: 1;
    grid-row: 1;
    justify-self: center;
  }

  .topbar-actions {
    grid-column: 1;
    grid-row: 2;
    justify-self: stretch;
    justify-content: space-between;
    min-width: 0;
  }

  .icon-button {
    min-width: 2.75rem;
    min-height: 2.75rem;
  }

  .streak-pill {
    min-height: 2.75rem;
  }

  .mode-switcher {
    grid-column: 1;
    grid-row: 3;
    justify-self: stretch;
    width: 100%;
    min-width: 0;
  }
}

@media (pointer: coarse) {
  .mode-button,
  .icon-button,
  .transform-controls button,
  .result-banner .result-buttons button,
  .share-challenge-actions button {
    min-height: 3rem;
  }

  .icon-button {
    min-width: 2.75rem;
  }

  .streak-pill {
    min-height: 2.75rem;
  }
}

@media (hover: none) {
  .piece-card:hover {
    transform: none;
    box-shadow: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}