/* ============ Design tokens ============ */
/* Colour tokens. Every text colour below was checked against the page background,
   the translucent panels and the glowing background orbs (WCAG AA, 4.5:1 for normal text). */
:root {
  color-scheme: dark;
  --bg: #0b0f1a;
  --bg-soft: #121829;
  --panel: rgba(255, 255, 255, 0.05);
  --panel-strong: rgba(255, 255, 255, 0.09);
  --border: rgba(255, 255, 255, 0.14);
  --border-strong: rgba(255, 255, 255, 0.24);
  --text: #f1f4ff;
  /* headings, important text */
  --text-body: #cbd3ec;
  /* paragraphs and long reading */
  --text-dim: #b0bad6;
  /* secondary text */
  --text-faint: #a2adcb;
  /* small print (still readable) */
  --accent: #6d4cf5;
  /* buttons: white text on this is 5.2:1 */
  --accent-2: #22d3ee;
  --accent-3: #ff4d8d;
  --good: #34d399;
  --warn: #fbbf24;
  --bad: #fb8a8a;
  --on-accent: #ffffff;
  --grad: linear-gradient(120deg, #7c5cff 0%, #22d3ee 55%, #ff4d8d 100%);
  --shadow: 0 24px 60px -20px rgba(0, 0, 0, 0.75);
  --radius: 20px;
  --radius-sm: 13px;
  --font: "Space Grotesk", system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
}

/* Light theme: the bright cyan / green / amber / red used on dark are far too pale on a light
   page, so the light theme uses deeper versions of the same hues. */
[data-theme="light"] {
  color-scheme: light;
  --bg: #eef1f8;
  --bg-soft: #ffffff;
  --panel: rgba(15, 20, 40, 0.04);
  --panel-strong: rgba(15, 20, 40, 0.08);
  --border: rgba(15, 20, 40, 0.16);
  --border-strong: rgba(15, 20, 40, 0.3);
  --text: #12172b;
  --text-body: #2c3652;
  --text-dim: #3f4a68;
  --text-faint: #4f5b78;
  --accent: #5236e0;
  --accent-2: #086480;
  --accent-3: #b3124f;
  --good: #046c4e;
  --warn: #7a5000;
  --bad: #b42323;
  --grad: linear-gradient(120deg, #5236e0 0%, #086480 55%, #b3124f 100%);
  --shadow: 0 24px 60px -24px rgba(40, 50, 90, 0.4);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  -webkit-tap-highlight-color: transparent;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  transition: background 0.35s ease, color 0.35s ease;
}

::selection {
  background: var(--accent);
  color: var(--on-accent);
}

/* ============ Background orbs ============ */
.bg-orbs {
  position: fixed;
  inset: 0;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: 0.32;
}

.orb-1 {
  width: 460px;
  height: 460px;
  background: #7c5cff;
  top: -140px;
  left: -120px;
  animation: drift 24s ease-in-out infinite;
}

.orb-2 {
  width: 420px;
  height: 420px;
  background: #22d3ee;
  bottom: -160px;
  right: -100px;
  opacity: 0.26;
  animation: drift 30s ease-in-out infinite reverse;
}

.orb-3 {
  width: 340px;
  height: 340px;
  background: #ff4d8d;
  top: 40%;
  left: 55%;
  opacity: 0.2;
  animation: drift 36s ease-in-out infinite;
}

[data-theme="light"] .orb {
  opacity: 0.16;
}

[data-theme="light"] .orb-3 {
  opacity: 0.1;
}

@keyframes drift {

  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }

  50% {
    transform: translate(40px, -30px) scale(1.12);
  }
}

/* ============ Header ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px clamp(16px, 4vw, 44px);
  backdrop-filter: blur(14px);
  background: color-mix(in srgb, var(--bg) 72%, transparent);
  border-bottom: 1px solid var(--border);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}

.brand-mark {
  font-size: 1.4rem;
  filter: drop-shadow(0 4px 12px rgba(124, 92, 255, 0.6));
}

.brand-name {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.header-nav {
  display: flex;
  gap: 8px;
}

.ghost-btn {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  font-size: 1.1rem;
  display: grid;
  place-items: center;
  transition: transform 0.15s, background 0.2s, border-color 0.2s;
}

.ghost-btn:hover {
  background: var(--panel-strong);
  border-color: var(--border-strong);
  transform: translateY(-2px);
}

/* ============ Views ============ */
#app {
  flex: 1;
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: clamp(20px, 4vw, 40px) clamp(16px, 4vw, 44px) 60px;
}

.view {
  display: none;
  animation: fade-up 0.45s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.view.is-active {
  display: block;
}

@keyframes fade-up {
  from {
    opacity: 0;
    transform: translateY(16px);
  }

  to {
    opacity: 1;
    transform: none;
  }
}

/* ============ Hero ============ */
.hero {
  text-align: center;
  margin: 30px 0 44px;
}

.hero-kicker {
  color: var(--accent-2);
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.72rem;
  margin: 0 0 14px;
}

.hero-title {
  font-size: clamp(2.1rem, 6.5vw, 4rem);
  line-height: 1.02;
  margin: 0 0 16px;
  letter-spacing: -0.03em;
  font-weight: 700;
}

.hero-title .grad {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  color: var(--text-body);
  max-width: 520px;
  margin: 0 auto;
  font-size: clamp(0.95rem, 2.4vw, 1.1rem);
}

/* ============ Game grid ============ */
.game-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 20px;
}

.game-card {
  position: relative;
  text-align: left;
  cursor: pointer;
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: var(--radius);
  padding: 24px;
  color: var(--text);
  font-family: inherit;
  text-decoration: none;
  transition: transform 0.25s cubic-bezier(0.2, 0.8, 0.2, 1), border-color 0.25s, box-shadow 0.25s;
  backdrop-filter: blur(12px);
}

.game-card:hover,
.game-card:focus,
.game-card:visited {
  text-decoration: none;
  color: var(--text);
}

.game-card::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  background: radial-gradient(240px 140px at var(--mx, 50%) var(--my, 0%), rgba(255, 255, 255, 0.12), transparent 70%);
  opacity: 0;
  transition: opacity 0.3s;
}

.game-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-strong);
  box-shadow: var(--shadow);
}

.game-card:hover::after {
  opacity: 1;
}

.game-card:focus-visible {
  outline: 2px solid var(--accent-2);
  outline-offset: 2px;
}

.card-icon {
  font-size: 2.4rem;
  line-height: 1;
  margin-bottom: 14px;
  display: block;
  font-family: "Apple Color Emoji", "Segoe UI Emoji", "Noto Color Emoji", "Twemoji Mozilla", "EmojiOne Color", sans-serif;
  filter: drop-shadow(0 8px 18px rgba(0, 0, 0, 0.4));
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 0 0 6px;
  letter-spacing: -0.01em;
}

.card-desc {
  color: var(--text-body);
  font-size: 0.9rem;
  margin: 0 0 16px;
  line-height: 1.5;
}

.card-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.card-tag {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 5px 10px;
  border-radius: 999px;
  background: var(--panel-strong);
  color: var(--text-dim);
  border: 1px solid var(--border);
}

.card-best {
  font-size: 0.8rem;
  color: var(--text-dim);
  font-family: var(--mono);
}

.card-play {
  position: absolute;
  top: 22px;
  right: 22px;
  font-size: 1.1rem;
  opacity: 0;
  transform: translateX(-6px);
  transition: 0.25s;
  color: var(--accent-2);
}

.game-card:hover .card-play {
  opacity: 1;
  transform: none;
}

/* ============ Game view top bar ============ */
.game-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  padding: 10px 16px;
  border-radius: 12px;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.9rem;
  transition: 0.2s;
}

.back-btn:hover {
  background: var(--panel-strong);
  transform: translateX(-2px);
}

.back-arrow {
  font-size: 1.1rem;
}

.game-heading,
.game-head {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1;
  min-width: 180px;
}

.game-emoji {
  font-size: 2rem;
}

.game-heading h2,
.game-titles h1 {
  margin: 0;
  font-size: 1.3rem;
  letter-spacing: -0.02em;
}

.game-heading p,
.game-titles p {
  margin: 2px 0 0;
  color: var(--text-dim);
  font-size: 0.82rem;
}

.game-actions {
  display: flex;
  gap: 8px;
}

.pill-btn {
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  padding: 10px 16px;
  border-radius: 12px;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.86rem;
  transition: 0.2s;
}

.pill-btn:hover {
  background: var(--panel-strong);
  border-color: var(--border-strong);
  transform: translateY(-2px);
}

.pill-btn.primary {
  background: var(--accent);
  border-color: transparent;
  color: var(--on-accent);
  box-shadow: 0 10px 24px -10px var(--accent);
}

.pill-btn.primary:hover {
  filter: brightness(0.92);
}

/* ============ Score strip ============ */
.score-strip {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.score-chip {
  flex: 1;
  min-width: 96px;
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  transition: border-color 0.25s, box-shadow 0.25s;
}

.score-chip .label {
  display: block;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-dim);
  font-weight: 600;
}

.score-chip .value {
  font-family: var(--mono);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  display: inline-block;
}

.score-chip.accent .value {
  color: var(--accent-2);
}

.score-chip.bump {
  border-color: var(--accent-2);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent-2) 22%, transparent);
}

.score-chip.bump .value {
  animation: value-bump 0.35s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.score-chip.bump-down {
  border-color: var(--bad);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--bad) 22%, transparent);
}

.score-chip.bump-down .value {
  animation: value-bump-down 0.35s cubic-bezier(0.2, 0.8, 0.2, 1);
}

@keyframes value-bump {
  0% {
    transform: scale(1);
  }

  40% {
    transform: scale(1.35);
    color: var(--good);
  }

  100% {
    transform: scale(1);
  }
}

@keyframes value-bump-down {
  0% {
    transform: scale(1);
  }

  40% {
    transform: scale(1.3);
    color: var(--bad);
  }

  100% {
    transform: scale(1);
  }
}

/* ============ Stage ============ */
.stage {
  position: relative;
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: var(--radius);
  padding: clamp(16px, 3vw, 28px);
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow);
}

.stage.center {
  display: grid;
  place-items: center;
}

/* ============ Shared game bits ============ */
.board-status {
  text-align: center;
  font-weight: 600;
  margin-bottom: 16px;
  min-height: 24px;
  font-size: 1.05rem;
}

.board-status.win {
  color: var(--good);
}

.board-status.lose {
  color: var(--bad);
}

.board-status.draw {
  color: var(--warn);
}

.overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  text-align: center;
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: blur(6px);
  border-radius: var(--radius);
  z-index: 5;
  padding: 24px;
  animation: overlay-in 0.34s cubic-bezier(0.2, 0.9, 0.3, 1.15);
}

.overlay h3 {
  font-size: 1.6rem;
  margin: 0 0 8px;
  letter-spacing: -0.02em;
}

.overlay p {
  color: var(--text-dim);
  margin: 0 0 18px;
}

.overlay-actions {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}

@keyframes overlay-in {
  from {
    opacity: 0;
    transform: scale(0.86);
  }

  to {
    opacity: 1;
    transform: scale(1);
  }
}

.vs-btns {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-bottom: 18px;
  flex-wrap: wrap;
}

.seg {
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text-dim);
  padding: 8px 14px;
  border-radius: 10px;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.84rem;
  transition: 0.2s;
}

.seg:hover {
  color: var(--text);
}

.seg.active {
  background: var(--accent);
  color: #fff;
  border-color: transparent;
}

/* ============ Tic-Tac-Toe ============ */
.ttt-board {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  width: min(340px, 100%);
  margin: 0 auto;
  aspect-ratio: 1;
}

.ttt-cell {
  position: relative;
  border: 1px solid var(--border);
  background: var(--panel-strong);
  border-radius: 16px;
  font-size: clamp(2rem, 9vw, 3rem);
  font-weight: 700;
  color: var(--text);
  cursor: pointer;
  display: grid;
  place-items: center;
  font-family: var(--font);
  transition: transform 0.15s, background 0.2s;
  user-select: none;
}

.ttt-cell::after {
  content: attr(data-mark);
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s;
}

.ttt-cell:not(.taken):hover::after {
  opacity: 0.3;
}

.ttt-cell:hover:not(.taken) {
  background: var(--panel-strong);
  border-color: var(--border-strong);
  transform: scale(1.04);
}

.ttt-cell.taken {
  cursor: default;
}

.ttt-cell.x {
  color: var(--accent-2);
}

.ttt-cell.o {
  color: var(--accent-3);
}

.ttt-cell.win {
  background: color-mix(in srgb, var(--good) 26%, transparent);
  border-color: var(--good);
  animation: pop 0.4s;
}

@keyframes pop {

  0%,
  100% {
    transform: scale(1);
  }

  50% {
    transform: scale(1.1);
  }
}

/* ============ Memory ============ */
.mem-board {
  display: grid;
  gap: 10px;
  margin: 0 auto;
  width: min(520px, 100%);
}

.mem-card {
  position: relative;
  aspect-ratio: 3 / 4;
  perspective: 800px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 0;
}

.mem-inner {
  position: absolute;
  inset: 0;
  transition: transform 0.45s cubic-bezier(0.2, 0.8, 0.2, 1);
  transform-style: preserve-3d;
}

.mem-card.flipped .mem-inner,
.mem-card.matched .mem-inner {
  transform: rotateY(180deg);
}

.mem-face {
  position: absolute;
  inset: 0;
  border-radius: var(--radius-sm);
  display: grid;
  place-items: center;
  backface-visibility: hidden;
  border: 1px solid var(--border);
}

.mem-front {
  background: linear-gradient(145deg, var(--panel-strong), var(--panel));
  font-size: 1.6rem;
  color: var(--text-faint);
}

.mem-back {
  transform: rotateY(180deg);
  font-size: clamp(1.5rem, 6vw, 2.4rem);
  background: var(--panel-strong);
}

.mem-card.matched .mem-back {
  background: color-mix(in srgb, var(--good) 22%, transparent);
  border-color: var(--good);
}

.mem-card.matched {
  animation: pop 0.4s;
}

/* ============ Snake / canvas games ============ */
.canvas-wrap {
  position: relative;
  display: grid;
  place-items: center;
}

canvas.game-canvas {
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: #0a0e18;
  max-width: 100%;
  height: auto;
  touch-action: none;
  display: block;
}

.pad {
  display: grid;
  grid-template-columns: repeat(3, 56px);
  grid-template-rows: repeat(3, 56px);
  gap: 6px;
  margin: 18px auto 0;
  justify-content: center;
}

.pad button {
  border: 1px solid var(--border);
  background: var(--panel-strong);
  color: var(--text);
  border-radius: 12px;
  font-size: 1.3rem;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: 0.15s;
}

.pad button:active {
  background: var(--accent);
  transform: scale(0.94);
}

.pad .pad-up {
  grid-area: 1 / 2;
}

.pad .pad-left {
  grid-area: 2 / 1;
}

.pad .pad-center {
  grid-area: 2 / 2;
}

.pad .pad-right {
  grid-area: 2 / 3;
}

.pad .pad-down {
  grid-area: 3 / 2;
}

@media (hover: hover) and (pointer: fine) {
  .pad {
    display: none;
  }
}

/* ============ 2048 ============ */
.g2048-board {
  position: relative;
  display: grid;
  gap: 10px;
  padding: 10px;
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--bg) 60%, transparent);
  border: 1px solid var(--border);
  width: min(460px, 100%);
  aspect-ratio: 1;
  margin: 0 auto;
}

.g2048-cell {
  border-radius: 10px;
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-weight: 700;
  font-size: clamp(1rem, 4.4vw, 1.7rem);
  background: var(--panel);
  color: var(--text);
  transition: transform 0.12s;
  letter-spacing: -0.03em;
}

.g2048-cell.empty {
  background: color-mix(in srgb, var(--panel) 50%, transparent);
}

.g2048-cell.spawn {
  animation: pop 0.2s;
}

/* ============ Whack-a-mole ============ */
.wam-board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  width: min(430px, 100%);
  margin: 0 auto;
}

.hole {
  position: relative;
  aspect-ratio: 1;
  border-radius: 50%;
  background: radial-gradient(circle at 50% 35%, rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.75));
  border: 1px solid var(--border);
  overflow: hidden;
  cursor: pointer;
}

.hole::after {
  content: "";
  position: absolute;
  left: 12%;
  right: 12%;
  bottom: 8%;
  height: 22%;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.55);
}

.mole {
  position: absolute;
  left: 50%;
  bottom: 0;
  width: 72%;
  height: 82%;
  transform: translate(-50%, 105%);
  transition: transform 0.18s ease-out;
  font-size: clamp(1.8rem, 8vw, 3rem);
  display: grid;
  place-items: center;
  border-radius: 50% 50% 44% 44%;
  background: linear-gradient(160deg, #a8764f, #7c5236);
  z-index: 1;
}

.mole::before {
  content: "🐹";
}

.hole.up .mole {
  transform: translate(-50%, 8%);
}

.hole.bonk .mole::before {
  content: "💥";
}

.hole.gold .mole {
  background: linear-gradient(160deg, #ffe68a, #f2b730);
}

.hole.gold .mole::before {
  content: "🌟";
}

.hole.bomb .mole {
  background: linear-gradient(160deg, #5b6478, #363c4c);
}

.hole.bomb .mole::before {
  content: "💣";
}

.wam-timebar {
  height: 8px;
  border-radius: 999px;
  background: var(--panel-strong);
  overflow: hidden;
  margin: 0 auto 14px;
  width: min(430px, 100%);
  border: 1px solid var(--border);
}

.wam-timebar>i {
  display: block;
  height: 100%;
  width: 100%;
  background: linear-gradient(90deg, var(--good), var(--accent-2));
  transition: width 0.35s linear;
}

.wam-timebar.low>i {
  background: linear-gradient(90deg, var(--warn), var(--bad));
}

.hole.gold-flash {
  animation: gold-glow 0.5s ease;
}

@keyframes gold-glow {
  0% {
    box-shadow: 0 0 0 0 rgba(251, 191, 36, 0.8);
  }

  100% {
    box-shadow: 0 0 0 16px rgba(251, 191, 36, 0);
  }
}

/* ============ Tetris ============ */
.tetris-wrap {
  display: flex;
  gap: 18px;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  --tc: clamp(14px, min(4.6vw, 3.6vh), 22px);
}

.tetris-play {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

/* Tetris enhancements */
.tetris-cell {
  position: relative;
  border-radius: 3px;
  transition: background-color .06s linear;
}

/* Ghost piece — tinted outline in the piece's own colour */
.tetris-cell.ghost {
  background: transparent !important;
  box-shadow: inset 0 0 0 2px var(--tc, #fff);
  opacity: .38;
}

/* Row being cleared — bright flash before removal */
.tetris-cell.clearing {
  animation: tetris-flash .22s ease-out;
}

@keyframes tetris-flash {
  0% {
    transform: scale(1);
    filter: brightness(1);
  }

  40% {
    transform: scale(1.08);
    filter: brightness(2.4);
  }

  100% {
    transform: scale(1);
    filter: brightness(2);
  }
}

@media (prefers-reduced-motion: reduce) {
  .tetris-cell {
    transition: none;
  }

  .tetris-cell.clearing {
    animation: none;
    filter: brightness(1.8);
  }
}

.tetris-board {
  display: grid;
  grid-template-columns: repeat(10, var(--tc));
  grid-template-rows: repeat(20, var(--tc));
  gap: 2px;
  padding: 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--bg) 60%, transparent);
}

.tetris-side {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  padding-top: 4px;
}

.tetris-next-label {
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
  font-weight: 600;
}

.tetris-next {
  display: grid;
  grid-template-columns: repeat(4, var(--tc));
  grid-template-rows: repeat(4, var(--tc));
  gap: 2px;
  padding: 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--bg) 60%, transparent);
}

.tetris-controls {
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
}

.tetris-controls button {
  min-width: 54px;
  height: 48px;
  padding: 0 14px;
  border: 1px solid var(--border);
  background: var(--panel-strong);
  color: var(--text);
  border-radius: 12px;
  font-size: 1.05rem;
  font-weight: 700;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: 0.15s;
}

.tetris-controls button:active {
  background: var(--accent);
  transform: scale(0.94);
}

/* ============ Sliding Puzzle ============ */
.sl-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

.sl-board {
  display: grid;
  gap: 6px;
  padding: 8px;
  width: min(92vw, 360px);
  aspect-ratio: 1 / 1;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--bg) 60%, transparent);
}

.sl-tile {
  display: grid;
  place-items: center;
  aspect-ratio: 1 / 1;
  border: 1px solid var(--border);
  background: var(--panel-strong);
  color: var(--text);
  border-radius: 10px;
  font-family: inherit;
  font-weight: 700;
  font-size: clamp(1rem, 5vw, 1.7rem);
  cursor: pointer;
  transition: 0.12s;
}

.sl-tile:hover:not(.empty) {
  background: var(--accent);
  border-color: transparent;
  color: #fff;
}

.sl-tile:active:not(.empty) {
  transform: scale(0.96);
}

.sl-tile.empty {
  background: transparent;
  border-color: transparent;
  cursor: default;
}

/* ============ Interaction feedback ============ */
.play-hint {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 16px;
  z-index: 3;
  color: #eef2ff;
  font-weight: 600;
  background: rgba(6, 9, 18, 0.5);
  border-radius: var(--radius-sm);
  pointer-events: none;
  animation: hint-pulse 2s ease-in-out infinite;
}

@keyframes hint-pulse {

  0%,
  100% {
    opacity: 0.82;
  }

  50% {
    opacity: 1;
  }
}

.pop-text {
  position: absolute;
  z-index: 6;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 1.1rem;
  color: #ffffff;
  pointer-events: none;
  transform: translate(-50%, -50%);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.85), 0 2px 10px rgba(0, 0, 0, 0.7);
}

.pop-text.gain {
  color: #4ade80;
}

.pop-text.loss {
  color: #ff9a9a;
}

.pop-text.gold {
  color: #fcd34d;
}

.confetti-layer {
  position: fixed;
  inset: 0;
  z-index: 80;
  pointer-events: none;
  overflow: hidden;
}

.confetti {
  position: absolute;
  top: -22px;
  display: block;
  will-change: transform;
}

.shake {
  animation: shake 0.32s cubic-bezier(0.36, 0.07, 0.19, 0.97);
}

@keyframes shake {

  10%,
  90% {
    transform: translateX(-2px);
  }

  20%,
  80% {
    transform: translateX(4px);
  }

  30%,
  50%,
  70% {
    transform: translateX(-6px);
  }

  40%,
  60% {
    transform: translateX(6px);
  }
}

.g2048-cell.merge {
  animation: merge-pop 0.22s ease-out;
}

@keyframes merge-pop {
  0% {
    transform: scale(1);
  }

  50% {
    transform: scale(1.18);
  }

  100% {
    transform: scale(1);
  }
}

.pill-btn:active,
.back-btn:active,
.ghost-btn:active,
.seg:active {
  transform: translateY(1px) scale(0.98);
}

/* ============ Modal ============ */
.modal {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: none;
  place-items: center;
  padding: 20px;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(4px);
}

.modal.open {
  display: grid;
  animation: fade-up 0.25s;
}

.modal-card {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  max-width: 460px;
  width: 100%;
  box-shadow: var(--shadow);
}

.modal-card h3 {
  margin: 0 0 14px;
  font-size: 1.3rem;
}

.modal-card ul {
  margin: 0 0 20px;
  padding-left: 20px;
  color: var(--text-dim);
  line-height: 1.7;
}

.modal-card li::marker {
  color: var(--accent-2);
}

.modal-card kbd {
  font-family: var(--mono);
  font-size: 0.8em;
  background: var(--panel-strong);
  border: 1px solid var(--border);
  border-bottom-width: 2px;
  border-radius: 6px;
  padding: 1px 7px;
  color: var(--text);
}

/* ============ Toast ============ */
.toast {
  position: fixed;
  bottom: 26px;
  left: 50%;
  transform: translate(-50%, 120%);
  z-index: 70;
  background: var(--bg-soft);
  border: 1px solid var(--border-strong);
  color: var(--text);
  padding: 12px 20px;
  border-radius: 12px;
  font-weight: 600;
  box-shadow: var(--shadow);
  transition: transform 0.35s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.toast.show {
  transform: translate(-50%, 0);
}

/* ============ Footer ============ */
.site-footer {
  position: relative;
  z-index: 1;
  margin-top: auto;
  text-align: center;
  padding: 30px 20px calc(30px + env(safe-area-inset-bottom, 0px));
  color: var(--text-dim);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
}

.site-footer p {
  margin: 0;
}

.footer-copy {
  opacity: 0.9;
}

/* ============ SEO content / long-form ============ */
.skip-link {
  position: absolute;
  left: 12px;
  top: -64px;
  z-index: 100;
  background: var(--accent);
  color: #fff;
  padding: 10px 16px;
  border-radius: 10px;
  font-weight: 600;
  text-decoration: none;
  transition: top 0.2s;
}

.skip-link:focus {
  top: 12px;
}

.section-heading {
  font-size: clamp(1.4rem, 3.6vw, 1.9rem);
  letter-spacing: -0.02em;
  margin: 52px 0 22px;
}

.header-nav {
  align-items: center;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  height: 42px;
  padding: 0 14px;
  border-radius: 12px;
  text-decoration: none;
  color: var(--text-dim);
  font-weight: 600;
  font-size: 0.88rem;
  transition: 0.2s;
}

.nav-link:hover {
  color: var(--text);
  background: var(--panel);
}

.breadcrumbs {
  margin: 0 0 16px;
  font-size: 0.85rem;
  color: var(--text-dim);
}

.breadcrumbs ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  margin: 0;
  padding: 0;
}

.breadcrumbs li {
  display: flex;
  align-items: center;
}

.breadcrumbs li+li::before {
  content: "/";
  margin: 0 8px;
  color: var(--text-faint);
}

.breadcrumbs a {
  color: var(--text-dim);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--accent-2);
}

.breadcrumbs [aria-current] {
  color: var(--text);
  font-weight: 600;
}

/* ============ Policy table of contents ============ */
.policy-toc {
  margin: 4px 0 30px;
  padding: 20px 22px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--panel);
}

.policy-toc h2 {
  margin: 0 0 12px;
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.policy-toc ol {
  margin: 0;
  padding-left: 18px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 8px 26px;
  font-size: 0.9rem;
}

.policy-toc a {
  color: var(--text-dim);
  text-decoration: none;
}

.policy-toc a:hover {
  color: var(--accent-2);
  text-decoration: underline;
}

.content section {
  scroll-margin-top: 88px;
}

.content {
  max-width: 760px;
  margin: 48px auto 0;
  line-height: 1.75;
  color: var(--text-body);
}

.content>h2 {
  color: var(--text);
  font-size: clamp(1.25rem, 3.4vw, 1.6rem);
  margin: 44px 0 12px;
  letter-spacing: -0.02em;
}

.content>h2:first-child {
  margin-top: 0;
}

.content h3 {
  color: var(--text);
  font-size: 1.08rem;
  margin: 24px 0 8px;
}

.content p {
  margin: 0 0 14px;
}

.content ul,
.content ol {
  margin: 0 0 16px;
  padding-left: 22px;
}

.content li {
  margin: 6px 0;
}

.content a {
  color: var(--accent-2);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.content strong {
  color: var(--text);
}

.faq details {
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: var(--radius-sm);
  padding: 2px 18px;
  margin: 0 0 10px;
}

.faq details[open] {
  border-color: var(--border-strong);
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--text);
  padding: 15px 0;
  list-style: none;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq summary::after {
  content: "+";
  color: var(--accent-2);
  font-weight: 700;
  font-size: 1.2rem;
  line-height: 1;
}

.faq details[open] summary::after {
  content: "\2212";
}

.faq p {
  margin: 0 0 15px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 16px;
  margin: 20px 0 8px;
}

.feature {
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: var(--radius-sm);
  padding: 20px;
}

.feature h3 {
  margin: 0 0 6px;
  color: var(--text);
  font-size: 1rem;
}

.feature p {
  margin: 0;
  font-size: 0.9rem;
}

.guide-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.guide-list li {
  margin: 0 0 12px;
  padding-left: 0;
}

.game-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 34px;
}

.game-nav a {
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: 10px;
  padding: 10px 14px;
  text-decoration: none;
  color: var(--text);
  font-weight: 600;
  font-size: 0.85rem;
}

.game-nav a:hover {
  border-color: var(--border-strong);
}

.game-nav a[aria-current] {
  border-color: var(--accent);
  color: var(--accent-2);
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  justify-content: center;
  margin-bottom: 12px;
}

.site-footer nav a {
  color: var(--text-dim);
  text-decoration: none;
}

.site-footer nav a:hover {
  color: var(--accent-2);
}

.game-heading h1 {
  margin: 0;
  font-size: 1.3rem;
  letter-spacing: -0.02em;
}

a.back-btn {
  text-decoration: none;
}

/* ============ Responsive ============ */
@media (max-width: 640px) {
  .score-strip {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
  }

  .score-chip:last-child:nth-child(odd) {
    grid-column: 1 / -1;
  }

  .game-heading p {
    display: none;
  }

  .game-topbar {
    gap: 10px;
  }

  .back-btn {
    padding: 9px 13px;
    font-size: 0.82rem;
  }

  .pill-btn {
    padding: 9px 13px;
    font-size: 0.8rem;
  }
}

@media (prefers-reduced-motion: reduce) {

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.05ms !important;
  }
}

/* ============ Accessibility ============ */
:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--accent-2);
  outline-offset: 2px;
}

@media (prefers-contrast: more) {
  :root {
    --text-body: #e2e8fa;
    --text-dim: #d4daf0;
    --text-faint: #c3cbe4;
    --border: rgba(255, 255, 255, 0.34);
    --border-strong: rgba(255, 255, 255, 0.5);
  }

  [data-theme="light"] {
    --text-body: #151b30;
    --text-dim: #1f2742;
    --text-faint: #2c3552;
    --border: rgba(15, 20, 40, 0.45);
    --border-strong: rgba(15, 20, 40, 0.65);
  }
}