.hero { text-align: center; padding: 24px 0 12px; }
.hero h1 {
  font-size: clamp(48px, 10vw, 80px);
  font-weight: 900;
  color: var(--red);
  text-shadow: 3px 3px 0 var(--gold), 6px 6px 0 var(--ink);
  letter-spacing: 2px;
  transform: rotate(-2deg);
  line-height: 1;
}
.tagline { color: var(--ink-2); font-weight: 700; margin-top: 8px; }

.numerkle-shell {
  max-width: 520px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
  align-items: center;
}

/* Wordle-like board, 6 digit columns */
.board {
  display: grid;
  grid-template-rows: repeat(6, 1fr);
  gap: 6px;
  width: 100%;
  max-width: 360px;
}
.board-row {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 5px;
}
.cell {
  aspect-ratio: 1;
  background: white;
  border: 3px solid var(--ink);
  border-radius: 8px;
  display: grid;
  place-items: center;
  font-size: clamp(18px, 5vw, 26px);
  font-weight: 900;
  color: var(--ink);
  box-shadow: 0 3px 0 var(--ink);
  transition: background 0.3s, color 0.3s, transform 0.15s;
}
.cell--filled { background: var(--paper); animation: pop 0.12s ease-out; }
.cell--current { border-color: var(--red); }
.cell--correct { background: #4caf50; color: white; border-color: #1b5e20; }
.cell--present { background: var(--gold); color: var(--ink); border-color: var(--gold-d); }
.cell--absent  { background: #666; color: #ccc; border-color: #333; }

@keyframes pop {
  0%   { transform: scale(0.8); }
  60%  { transform: scale(1.1); }
  100% { transform: scale(1); }
}

/* Equation hint strip */
.eq-hint {
  background: var(--paper);
  border: 3px solid var(--ink);
  border-radius: 12px;
  padding: 10px 18px;
  font-size: clamp(22px, 5vw, 28px);
  font-weight: 900;
  letter-spacing: 3px;
  color: var(--ink-2);
  box-shadow: 0 3px 0 var(--ink);
}
.eq-hint .op {
  color: var(--red);
  margin: 0 8px;
}

/* Holes canvas */
.holes-wrap {
  width: 100%;
  max-width: 520px;
  aspect-ratio: 5 / 3;
  background: radial-gradient(ellipse at top, #ffe5b0, #ffb86b);
  border: 4px solid var(--ink);
  border-radius: 16px;
  box-shadow: var(--shadow-hard);
  overflow: hidden;
}
#game {
  display: block;
  width: 100%;
  height: 100%;
  touch-action: none;
  cursor: none;
}

.hud-row { display: flex; gap: 10px; flex-wrap: wrap; justify-content: center; }
.hud-pill {
  background: rgba(0,0,0,0.8);
  color: var(--cream);
  padding: 8px 14px;
  border-radius: 999px;
  border: 2px solid var(--gold);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 1px;
}

.controls {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
}
.controls .zx-btn { padding: 10px 16px; font-size: 14px; }

.mode-tag {
  background: var(--gold);
  color: var(--ink);
  padding: 4px 12px;
  border-radius: 999px;
  border: 2px solid var(--ink);
  font-weight: 900;
  font-size: 11px;
  letter-spacing: 1px;
  box-shadow: 0 2px 0 var(--ink);
}
.mode-tag--practice { background: #8ed0ff; }

.info { text-align: center; color: var(--ink-2); font-weight: 700; min-height: 24px; padding: 0 12px; }
.info--warn { color: var(--red); animation: shake 0.3s; }
@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  75% { transform: translateX(6px); }
}

/* Overlay */
.overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(8px);
  display: grid; place-items: center;
  z-index: 100;
  padding: 20px;
}
.overlay[hidden] { display: none; }
.panel {
  background: var(--paper);
  border: 5px solid var(--red);
  border-radius: 20px;
  box-shadow: 0 12px 40px rgba(0,0,0,0.6);
  padding: 28px 32px;
  max-width: 440px;
  width: 100%;
  text-align: center;
  max-height: 90vh;
  overflow-y: auto;
}
.panel h2 {
  font-size: 32px;
  color: var(--red);
  text-shadow: 2px 2px 0 var(--gold);
  letter-spacing: 1px;
  margin-bottom: 8px;
}
.result-eq {
  font-size: 36px;
  font-weight: 900;
  letter-spacing: 4px;
  margin: 14px 0;
  color: var(--ink);
}
.share-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 3px;
  max-width: 240px;
  margin: 12px auto;
}
.share-grid div {
  aspect-ratio: 1;
  border-radius: 3px;
  background: #666;
}
.share-grid .s-correct { background: #4caf50; }
.share-grid .s-present { background: var(--gold); }

.how-list { text-align: left; padding-left: 20px; margin: 16px 0; line-height: 1.6; color: var(--ink-2); }
.how-list b { color: var(--red); }
.next-puzzle { color: var(--ink-2); font-size: 13px; margin: 12px 0; }
.panel .zx-btn { display: block; width: 100%; margin-top: 10px; }