:root {
  --ink: oklch(28% 0.04 55);
  --ink-soft: oklch(45% 0.03 55);
  --apricot: oklch(74% 0.14 50);
  --coral: oklch(66% 0.15 35);
  --night: oklch(32% 0.05 240);
  --mint: oklch(78% 0.08 145);
  --font-display: "ZCOOL KuaiLe", "Fredoka", system-ui, sans-serif;
  --font-body: "Fredoka", system-ui, sans-serif;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --surface: oklch(99% 0.01 90 / 0.82);
  --line: oklch(60% 0.03 55 / 0.14);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  min-height: 100dvh;
  font-family: var(--font-body);
  color: var(--ink);
  background:
    radial-gradient(120% 80% at 10% 0%, oklch(92% 0.05 85), transparent 55%),
    radial-gradient(90% 70% at 100% 20%, oklch(90% 0.04 220), transparent 50%),
    oklch(96% 0.02 95);
  padding: 20px 16px 40px;
  overflow-x: hidden;
}

.bg {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

.blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(40px);
  opacity: 0.45;
  animation: float 12s ease-in-out infinite;
}

.b1 {
  width: 280px;
  height: 280px;
  background: oklch(82% 0.1 55);
  top: -60px;
  left: -40px;
}

.b2 {
  width: 220px;
  height: 220px;
  background: oklch(80% 0.07 230);
  bottom: 10%;
  right: -50px;
  animation-delay: -4s;
}

.b3 {
  width: 160px;
  height: 160px;
  background: oklch(84% 0.08 145);
  top: 40%;
  left: 40%;
  animation-delay: -7s;
  opacity: 0.3;
}

@keyframes float {
  0%,
  100% { transform: translateY(0); }
  50% { transform: translateY(-18px); }
}

.hub {
  position: relative;
  z-index: 1;
  width: min(100%, clamp(320px, 92vw, 1040px));
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: clamp(10px, 1.5vw, 18px);
  animation: rise 0.55s var(--ease) both;
}

@keyframes rise {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: none; }
}

.hero {
  text-align: center;
  margin-bottom: 1.1rem;
}

.brand-logo {
  display: block;
  width: clamp(112px, 28vw, 168px);
  height: auto;
  margin: 0 auto 0.2rem;
  animation: logo-bob 3.2s ease-in-out infinite;
}

@keyframes logo-bob {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-5px); }
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.lead {
  margin-top: 0.15rem;
  font-size: 0.98rem;
  font-weight: 500;
  color: var(--ink-soft);
}

/* Category filter */
.cat-bar {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding: 2px 2px 10px;
  margin-bottom: 0.35rem;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.cat-chip {
  appearance: none;
  border: 1.5px solid var(--line);
  background: var(--surface);
  color: var(--ink-soft);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.88rem;
  padding: 0.55em 0.85em;
  border-radius: 14px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  white-space: nowrap;
  transition: background 0.2s, color 0.2s, border-color 0.2s, transform 0.2s var(--ease);
}

.cat-chip:hover {
  transform: translateY(-1px);
  color: var(--ink);
  border-color: oklch(70% 0.08 55 / 0.45);
}

.cat-chip.active {
  color: oklch(99% 0.02 90);
  background: linear-gradient(165deg, oklch(72% 0.12 50), var(--coral));
  border-color: transparent;
  box-shadow: 0 4px 0 oklch(48% 0.12 40);
}

.cat-count {
  font-size: 0.72rem;
  font-weight: 700;
  min-width: 1.35em;
  padding: 0.1em 0.4em;
  border-radius: 999px;
  background: oklch(50% 0.03 55 / 0.1);
  text-align: center;
}

.cat-chip.active .cat-count {
  background: oklch(100% 0.02 90 / 0.22);
  color: inherit;
}

.filter-hint {
  font-size: 0.9rem;
  color: var(--ink-soft);
  margin: 0 0 0.85rem;
  padding: 0.65rem 0.85rem;
  border-radius: 14px;
  background: oklch(99% 0.015 90 / 0.65);
  border: 1px solid var(--line);
}

.shelf {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.group-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 12px;
  margin-bottom: 0.75rem;
}

.group-title {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 4vw, 1.7rem);
  line-height: 1.15;
  letter-spacing: 0.02em;
}

.group-hint {
  margin-top: 0.2rem;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--ink-soft);
}

.group-more {
  appearance: none;
  border: none;
  background: transparent;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--coral);
  cursor: pointer;
  white-space: nowrap;
  padding: 0.35em 0.2em;
}

.group-more:hover {
  text-decoration: underline;
}

.games {
  display: grid;
  gap: 0.85rem;
}

@media (min-width: 640px) {
  .games {
    grid-template-columns: 1fr 1fr;
  }
}

@media (min-width: 960px) {
  .games {
    grid-template-columns: 1fr 1fr 1fr;
  }
}

.game {
  display: grid;
  grid-template-columns: 88px 1fr auto;
  align-items: start;
  gap: 0.85rem;
  padding: 0.9rem 1rem;
  text-decoration: none;
  color: inherit;
  border-radius: 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  box-shadow: 0 10px 28px oklch(40% 0.04 55 / 0.08);
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.game:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 34px oklch(40% 0.04 55 / 0.12);
}

.game:active {
  transform: translateY(1px);
}

.preview {
  width: 88px;
  height: 88px;
  border-radius: 16px;
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
}

.meta {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding-top: 0.1rem;
}

.name {
  font-family: var(--font-display);
  font-size: 1.28rem;
  line-height: 1.15;
}

.desc {
  font-size: 0.9rem;
  font-weight: 600;
  color: oklch(38% 0.04 55);
}

.how {
  font-size: 0.82rem;
  color: var(--ink-soft);
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.skills {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
  margin-top: 0.25rem;
}

.skill {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: oklch(42% 0.05 55);
  background: oklch(94% 0.025 80);
  padding: 0.2em 0.5em;
  border-radius: 999px;
}

.go {
  align-self: center;
  font-weight: 700;
  font-size: 0.88rem;
  color: var(--coral);
  white-space: nowrap;
  padding: 0.45em 0.15em;
}

.empty {
  color: var(--ink-soft);
  padding: 1rem;
}

@media (max-width: 520px) {
  .game {
    grid-template-columns: 72px 1fr;
    grid-template-rows: auto auto;
  }

  .preview {
    width: 72px;
    height: 72px;
    grid-row: span 2;
  }

  .go {
    grid-column: 2;
    justify-self: start;
    padding: 0;
  }

  .how {
    -webkit-line-clamp: 3;
  }
}

@media (prefers-reduced-motion: reduce) {
  .blob,
  .brand-logo,
  .hub,
  .game,
  .fish,
  .kitty,
  .runner-kitty,
  .bobber {
    animation: none !important;
    transition: none !important;
  }
}



.mole .preview { background: linear-gradient(180deg, #f7e0c0, #c4a574); }
.mole-hole {
  position: absolute; left: 28px; right: 28px; bottom: 10px; height: 28px;
  background: #3d2a1a; border-radius: 50%;
}
.mole-head {
  position: absolute; left: 50%; bottom: 22px; width: 26px; height: 24px;
  transform: translateX(-50%);
  background: #e8913a; border-radius: 50% 50% 40% 40%;
}
.mole .go { color: oklch(48% 0.1 55); }

.breakout .preview { background: linear-gradient(180deg, #2a3548, #1f2a44); }
.brk, .brk2 {
  position: absolute; height: 10px; border-radius: 2px; top: 16px;
}
.brk { left: 14px; width: 28px; background: #e76f51; }
.brk2 { left: 46px; width: 28px; background: #4d9de0; top: 30px; }
.paddle {
  position: absolute; left: 30px; right: 30px; bottom: 14px; height: 8px;
  background: #f4d35e; border-radius: 4px;
}
.breakout .go { color: oklch(70% 0.1 250); }

.maze .preview { background: linear-gradient(145deg, #dff5e6, #8fcf9f); }
.maze-wall {
  position: absolute; inset: 12px; border: 8px solid #3f8f5a; border-radius: 6px;
  border-right-width: 14px; border-bottom-width: 14px;
}
.maze-dot {
  position: absolute; left: 22px; top: 22px; width: 10px; height: 10px;
  background: #e8913a; border-radius: 50%;
}
.maze-star {
  position: absolute; right: 18px; bottom: 16px; color: #e9c46a; font-size: 14px;
}
.maze .go { color: oklch(42% 0.1 145); }

.sudoku .preview { background: linear-gradient(145deg, #efeaff, #b8a6f5); }
.su {
  position: absolute; width: 22px; height: 22px; border-radius: 6px;
  background: #fff; display: grid; place-items: center;
  font-size: 11px; font-weight: 800; color: #5b4db0;
  left: 18px; top: 16px;
}
.su.s2 { left: 44px; top: 16px; }
.su.s3 { left: 18px; top: 42px; }
.sudoku .go { color: oklch(45% 0.12 290); }

.connect4 .preview { background: linear-gradient(145deg, #7eb6ef, #3d7ec9); }
.c4 {
  position: absolute; width: 16px; height: 16px; border-radius: 50%;
  background: #e76f51; top: 22px;
}
.c4.a { left: 22px; }
.c4.b { left: 42px; background: #f4d35e; }
.c4.c { left: 62px; top: 40px; }
.connect4 .go { color: oklch(45% 0.12 250); }


.pinyin .preview { background: linear-gradient(145deg, #d6ecff, #5dade2); }
.py-hz {
  position: absolute; left: 16px; top: 14px;
  font-family: var(--font-display); font-size: 1.6rem; color: #1f4e79;
}
.py-py {
  position: absolute; right: 12px; bottom: 12px;
  background: #fff; padding: 0.15em 0.4em; border-radius: 8px;
  font-weight: 700; font-size: 0.85rem; color: #2874a6;
}
.pinyin .go { color: oklch(45% 0.1 240); }

.hanzi .preview { background: linear-gradient(145deg, #ffe6d5, #e8a87c); }
.hz-char {
  position: absolute; left: 16px; top: 12px;
  font-family: var(--font-display); font-size: 1.7rem; color: #6e2c00;
}
.hz-word {
  position: absolute; right: 12px; bottom: 14px;
  background: #fff; border-radius: 8px; padding: 0.2em 0.45em;
  font-weight: 700; font-size: 0.85rem; color: #a04000;
}
.hanzi .go { color: oklch(48% 0.1 50); }

.timestable .preview { background: linear-gradient(145deg, #fff0cc, #f5b041); }
.tt-q {
  position: absolute; left: 14px; top: 16px;
  font-family: var(--font-display); font-size: 1.2rem; color: #6e2c00;
}
.tt-a {
  position: absolute; right: 16px; bottom: 14px;
  width: 30px; height: 30px; border-radius: 8px; background: #fff;
  display: grid; place-items: center; font-weight: 800; color: #b9770e;
}
.timestable .go { color: oklch(48% 0.12 70); }

.units .preview { background: linear-gradient(145deg, #d5f5e3, #58d68d); }
.un-q {
  position: absolute; left: 14px; top: 18px; font-weight: 800; color: #145a32; font-size: 1rem;
}
.un-a {
  position: absolute; right: 12px; bottom: 14px;
  background: #fff; border-radius: 8px; padding: 0.2em 0.4em;
  font-weight: 800; font-size: 0.8rem; color: #196f3d;
}
.units .go { color: oklch(42% 0.12 145); }

.poetry .preview { background: linear-gradient(145deg, #f5eef8, #af7ac5); }
.po-line {
  position: absolute; left: 12px; top: 16px;
  font-family: var(--font-display); font-size: 0.95rem; color: #4a235a;
}
.po-ans {
  position: absolute; right: 12px; bottom: 14px;
  background: #fff; border-radius: 8px; padding: 0.2em 0.45em;
  font-weight: 700; font-size: 0.8rem; color: #6c3483;
}
.poetry .go { color: oklch(45% 0.12 320); }

.mathrush .preview { background: linear-gradient(145deg, #ffe4c4, #f0a35a); }
.math-q {
  position: absolute; left: 14px; top: 18px;
  font-family: var(--font-display); font-size: 1.1rem; color: #6a3f1f;
}
.math-a {
  position: absolute; right: 16px; bottom: 14px;
  width: 28px; height: 28px; border-radius: 8px; background: #fff;
  display: grid; place-items: center; font-weight: 800; color: #c45c2a;
}
.mathrush .go { color: oklch(48% 0.12 50); }

.catch .preview {
  background: linear-gradient(180deg, #b8dff0, #d4e8a8);
}

.run .preview {
  background: linear-gradient(180deg, #2a3548, #4a5d78 55%, #3d4f3a);
}

.lake .preview {
  background: linear-gradient(180deg, #f0d8a8 0%, #8ec0d4 45%, #3d8aab 100%);
}

.wave {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 34px;
  background: #3d8aab;
}

.bobber {
  position: absolute;
  top: 22px;
  right: 22px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: linear-gradient(180deg, #e76f51 50%, #fff8e7 50%);
  animation: bob 1.8s ease-in-out infinite;
  box-shadow: 0 -6px 0 -3px #2c2418;
}

.fisher {
  position: absolute;
  bottom: 10px;
  left: 14px;
  width: 26px;
  height: 20px;
  background: #f0a85a;
  border-radius: 50% 50% 40% 40%;
}

.fisher::before {
  content: "";
  position: absolute;
  width: 7px;
  height: 9px;
  background: #e8913a;
  border-radius: 40% 40% 0 0;
  top: -5px;
  left: 3px;
  transform: rotate(-18deg);
  box-shadow: 11px 1px 0 #e8913a;
}

.fisher::after {
  content: "";
  position: absolute;
  left: 20px;
  top: -18px;
  width: 2px;
  height: 28px;
  background: #5a4030;
  transform: rotate(35deg);
  border-radius: 2px;
}

.lake .go {
  color: oklch(45% 0.1 230);
}

.gomoku .preview {
  background: linear-gradient(145deg, #e0c49a, #b8956a);
}

.grid-mini {
  position: absolute;
  inset: 10px;
  background:
    linear-gradient(rgba(55, 40, 25, 0.35) 1px, transparent 1px) 0 0 / 14px 14px,
    linear-gradient(90deg, rgba(55, 40, 25, 0.35) 1px, transparent 1px) 0 0 / 14px 14px;
  border-radius: 4px;
}

.stone {
  position: absolute;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  box-shadow: 0 2px 3px rgba(0, 0, 0, 0.2);
}

.stone.s-black {
  background: radial-gradient(circle at 35% 30%, #555, #1a1a1a);
  left: 28px;
  top: 26px;
}

.stone.s-white {
  background: radial-gradient(circle at 35% 30%, #fff, #e8e0d0);
  right: 26px;
  bottom: 20px;
}

.gomoku .go {
  color: oklch(48% 0.08 55);
}


.weiqi .preview {
  background: linear-gradient(145deg, #e4c89a, #b08a55);
}

.wq-grid {
  position: absolute;
  inset: 10px;
  background:
    linear-gradient(rgba(55, 40, 25, 0.4) 1px, transparent 1px) 0 0 / 12px 12px,
    linear-gradient(90deg, rgba(55, 40, 25, 0.4) 1px, transparent 1px) 0 0 / 12px 12px;
  border-radius: 4px;
}

.stone.wq-b {
  left: 22px;
  top: 22px;
}

.stone.wq-w {
  right: 22px;
  bottom: 18px;
}

.weiqi .go {
  color: oklch(42% 0.06 55);
}


.memory .preview {
  background: linear-gradient(145deg, #d7ecff, #9ec9f5);
}
.mem-card {
  position: absolute;
  width: 28px;
  height: 36px;
  border-radius: 6px;
  box-shadow: 0 3px 0 rgba(60, 100, 160, 0.25);
}
.mem-card.a {
  left: 22px;
  top: 16px;
  background: linear-gradient(160deg, #7ec8ff, #5aa6f0);
  transform: rotate(-8deg);
}
.mem-card.b {
  right: 20px;
  bottom: 14px;
  background: #fff8ee;
  transform: rotate(10deg);
}
.mem-card.b::after {
  content: "🍓";
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-size: 14px;
}
.memory .go { color: oklch(45% 0.1 240); }

.simon .preview {
  background: linear-gradient(145deg, #f3e3ff, #d7b6f0);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  padding: 14px;
}
.simon-pad {
  border-radius: 8px;
  opacity: 0.9;
}
.simon-pad.g { background: #4caf71; }
.simon-pad.r { background: #e76f51; }
.simon-pad.y { background: #f4d35e; }
.simon-pad.b { background: #4d9de0; }
.simon .go { color: oklch(45% 0.12 320); }

.snake .preview {
  background: linear-gradient(145deg, #dff5d8, #a8d9a0);
}
.snake-body {
  position: absolute;
  left: 18px;
  top: 28px;
  width: 46px;
  height: 14px;
  border-radius: 8px;
  background: linear-gradient(90deg, #6fbf73, #3f8f4a);
  box-shadow: 14px -12px 0 #8fd18a;
}
.snake-food {
  position: absolute;
  right: 22px;
  top: 18px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #e76f51;
}
.snake .go { color: oklch(42% 0.1 145); }

.merge .preview {
  background: linear-gradient(145deg, #f0e0c8, #d7b48a);
}
.m2, .m4, .m8 {
  position: absolute;
  width: 26px;
  height: 26px;
  border-radius: 6px;
  display: grid;
  place-items: center;
  font-size: 11px;
  font-weight: 800;
  color: #776e65;
}
.m2 { left: 16px; top: 18px; background: #eee4da; }
.m4 { left: 36px; top: 28px; background: #ede0c8; }
.m8 { right: 18px; bottom: 14px; background: #f2b179; color: #fff; }
.merge .go { color: oklch(45% 0.1 55); }

.sliding .preview {
  background: linear-gradient(145deg, #dfe8ff, #aebff5);
}
.slide-n {
  position: absolute;
  width: 22px;
  height: 22px;
  border-radius: 6px;
  background: linear-gradient(160deg, #8eb0ff, #6a8ef0);
  color: #fff;
  font-size: 11px;
  font-weight: 800;
  display: grid;
  place-items: center;
  box-shadow: 0 2px 0 #4f6fc4;
}
.slide-n.n1 { left: 18px; top: 16px; }
.slide-n.n2 { left: 44px; top: 16px; }
.slide-n.n3 { left: 18px; top: 40px; }
.sliding .go { color: oklch(45% 0.1 270); }

.vocab .preview {
  background: linear-gradient(145deg, #fff6e8, #f0d9b5);
}

.vocab-card {
  position: absolute;
  left: 16px;
  top: 14px;
  width: 48px;
  height: 36px;
  background: #fff;
  border-radius: 6px;
  box-shadow: 0 3px 0 #e8c89a;
  transform: rotate(-8deg);
}

.vocab-card::before,
.vocab-card::after {
  content: "";
  position: absolute;
  left: 8px;
  right: 8px;
  height: 3px;
  background: #f0c090;
  border-radius: 2px;
}

.vocab-card::before {
  top: 10px;
}

.vocab-card::after {
  top: 18px;
  right: 16px;
}

.vocab-abc {
  position: absolute;
  right: 12px;
  bottom: 10px;
  font-family: var(--font-display);
  font-size: 1.15rem;
  color: #e8913a;
  animation: bob 2.4s ease-in-out infinite;
}

.vocab .go {
  color: oklch(52% 0.12 45);
}

.fish {
  position: absolute;
  width: 22px;
  height: 12px;
  background: #5eb1e8;
  border-radius: 50%;
  top: 14px;
  left: 14px;
  animation: bob 2.2s ease-in-out infinite;
}

.fish::after {
  content: "";
  position: absolute;
  right: -6px;
  top: 1px;
  border: 5px solid transparent;
  border-left-color: #5eb1e8;
}

.kitty {
  position: absolute;
  bottom: 8px;
  left: 34px;
  width: 28px;
  height: 22px;
  background: #f0a85a;
  border-radius: 50% 50% 45% 45%;
  animation: bob 2.2s ease-in-out infinite 0.2s;
}

.kitty::before,
.kitty::after {
  content: "";
  position: absolute;
  width: 8px;
  height: 10px;
  background: #e8913a;
  border-radius: 50% 50% 0 0;
  top: -6px;
}

.kitty::before {
  left: 4px;
  transform: rotate(-18deg);
}

.kitty::after {
  right: 4px;
  transform: rotate(18deg);
}

.roof {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 22px;
  background: #5a6b52;
}

.roof::before {
  content: "";
  position: absolute;
  left: 10px;
  bottom: 18px;
  width: 36px;
  height: 16px;
  background: #6d7f64;
  clip-path: polygon(0 100%, 50% 0, 100% 100%);
}

.runner-kitty {
  position: absolute;
  bottom: 20px;
  left: 48px;
  width: 26px;
  height: 20px;
  background: #f0a85a;
  border-radius: 50% 50% 40% 40%;
  animation: leap 1.6s var(--ease) infinite;
}

.runner-kitty::before {
  content: "";
  position: absolute;
  width: 7px;
  height: 9px;
  background: #e8913a;
  border-radius: 40% 40% 0 0;
  top: -5px;
  left: 3px;
  transform: rotate(-20deg);
  box-shadow: 12px 1px 0 #e8913a;
}

@keyframes bob {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-5px);
  }
}

@keyframes leap {
  0%,
  100% {
    transform: translate(0, 0);
  }
  40% {
    transform: translate(6px, -14px);
  }
  70% {
    transform: translate(10px, -2px);
  }
}


.run .go {
  color: oklch(48% 0.08 230);
}

.spot .preview { background: linear-gradient(145deg, #d6ecff, #5dade2); }
.spot-a, .spot-b {
  position: absolute; font-size: 1.35rem; top: 28px;
}
.spot-a { left: 18px; }
.spot-b { right: 18px; }
.spot .go { color: oklch(45% 0.1 240); }

.numtap .preview { background: linear-gradient(145deg, #d5f5e3, #48c78e); }
.nt-1, .nt-2, .nt-3 {
  position: absolute; width: 22px; height: 22px; border-radius: 6px;
  background: #fff; color: #1e8449; font-weight: 800; font-size: 0.75rem;
  display: grid; place-items: center;
}
.nt-1 { left: 16px; top: 18px; }
.nt-2 { left: 42px; top: 34px; }
.nt-3 { left: 28px; top: 54px; }
.numtap .go { color: oklch(42% 0.12 150); }

.oddone .preview { background: linear-gradient(145deg, #fdebd0, #f4a261); }
.odd-a, .odd-b { position: absolute; font-size: 1.4rem; top: 30px; }
.odd-a { left: 20px; }
.odd-b { right: 18px; }
.oddone .go { color: oklch(48% 0.12 55); }

.lights .preview { background: linear-gradient(145deg, #2c2440, #9b59b6); }
.lg {
  position: absolute; width: 18px; height: 18px; border-radius: 6px;
  background: #1a1428; top: 28px; left: 22px;
}
.lg.on { background: #f4d35e; box-shadow: 0 0 8px #f4d35e88; }
.lg.l2 { left: 48px; top: 48px; }
.lights .go { color: oklch(70% 0.12 310); }

.hanoi .preview { background: linear-gradient(145deg, #fdebd0, #e67e22); }
.hn-d {
  position: absolute; left: 50%; transform: translateX(-50%);
  height: 10px; border-radius: 5px; background: #e76f51;
}
.hn-d.d1 { width: 50px; bottom: 18px; background: #e9c46a; }
.hn-d.d2 { width: 38px; bottom: 30px; background: #f4a261; }
.hn-d.d3 { width: 26px; bottom: 42px; }
.hanoi .go { color: oklch(48% 0.12 50); }

.mines .preview { background: linear-gradient(145deg, #5d6d7e, #34495e); }
.mn {
  position: absolute; width: 20px; height: 20px; border-radius: 4px;
  background: #ecf0f1; color: #2980b9; font-size: 0.7rem; font-weight: 800;
  display: grid; place-items: center; left: 16px; top: 20px;
}
.mn.m2 { left: 40px; top: 36px; background: #e67e22; color: #fff; font-size: 0.55rem; }
.mn.m3 { left: 58px; top: 54px; color: #c0392b; }
.mines .go { color: oklch(70% 0.05 250); }

.tictactoe .preview { background: linear-gradient(145deg, #fadbd8, #e74c3c); }
.tt-x, .tt-o {
  position: absolute; font-family: var(--font-display); font-size: 1.6rem; font-weight: 700;
}
.tt-x { left: 18px; top: 16px; color: #c0392b; }
.tt-o { right: 18px; bottom: 14px; color: #2980b9; }
.tictactoe .go { color: oklch(48% 0.14 25); }

.reversi .preview { background: linear-gradient(145deg, #58d68d, #1e8449); }
.rv-b, .rv-w {
  position: absolute; width: 22px; height: 22px; border-radius: 50%;
  top: 32px;
}
.rv-b { left: 22px; background: #111; }
.rv-w { right: 22px; background: #fff; box-shadow: 0 1px 3px #0003; }
.reversi .go { color: oklch(42% 0.12 150); }

.boxes .preview { background: linear-gradient(145deg, #e8daef, #8e44ad); }
.bx-dot {
  position: absolute; width: 8px; height: 8px; border-radius: 50%;
  background: #5d4e6d; left: 22px; top: 22px;
  box-shadow: 36px 0 #5d4e6d, 0 36px #5d4e6d, 36px 36px #5d4e6d;
}
.bx-line {
  position: absolute; left: 26px; top: 24px; width: 32px; height: 4px;
  background: #e74c3c; border-radius: 2px;
}
.bx-box {
  position: absolute; left: 22px; top: 22px; width: 36px; height: 36px;
  background: #e74c3c22; border-radius: 2px;
}
.boxes .go { color: oklch(45% 0.12 310); }

.hub-foot {
  margin: 36px auto 8px;
  max-width: 720px;
  text-align: center;
  display: grid;
  gap: 10px;
  justify-items: center;
}

.hub-foot-text {
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.4;
}

.hub-clear-btn {
  appearance: none;
  border: 1px solid oklch(70% 0.03 55 / 0.35);
  background: oklch(99% 0.01 90 / 0.75);
  color: var(--ink-soft);
  font-family: var(--font-body);
  font-size: 0.88rem;
  font-weight: 600;
  padding: 0.55em 1.1em;
  border-radius: 999px;
  cursor: pointer;
  transition: transform 0.2s var(--ease), color 0.2s, border-color 0.2s;
}

.hub-clear-btn:hover {
  color: var(--ink);
  border-color: oklch(55% 0.08 35 / 0.45);
  transform: translateY(-1px);
}