:root {
  --bg: #1e293b;
  --panel: #0f172a;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --correct: #4ade80;
  --wrong: #f87171;
  --key: #334155;
  --key-hover: #475569;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, sans-serif;
  min-height: 100dvh;
  display: flex;
  justify-content: center;
  padding: 12px 10px 20px;
}

.game {
  width: 100%;
  max-width: 440px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

h1 {
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-align: center;
}

/* ---------- Score bar ---------- */
.score {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--panel);
  border-radius: 10px;
  padding: 8px 16px;
  width: 100%;
}
.score-side {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 1;
}
.score-side:last-child { justify-content: flex-end; }
.score-label { color: var(--muted); font-size: 0.85rem; }
.score-num   { font-size: 1.4rem; font-weight: 700; min-width: 1.5ch; text-align: center; }
.score-vs    { color: var(--muted); font-size: 0.8rem; }

.name-btn {
  background: none;
  border: 1px solid var(--key);
  border-radius: 6px;
  color: var(--muted);
  cursor: pointer;
  font-size: 0.85rem;
  padding: 2px 8px;
}
.name-btn:hover { border-color: var(--accent); color: var(--accent); }

.name-input {
  background: var(--key);
  border: 1px solid var(--accent);
  border-radius: 6px;
  color: var(--text);
  font-size: 0.85rem;
  padding: 2px 8px;
  width: 100px;
}

.name-list {
  background: var(--panel);
  border: 1px solid var(--key);
  border-radius: 6px;
  list-style: none;
  padding: 4px 0;
  position: absolute;
  z-index: 10;
  min-width: 120px;
}
.name-list li {
  cursor: pointer;
  font-size: 0.85rem;
  padding: 4px 12px;
}
.name-list li:hover { background: var(--key); }

/* ---------- Level toggle ---------- */
.level-toggle {
  display: flex;
  gap: 6px;
}
.level-btn {
  background: var(--key);
  border: 2px solid transparent;
  border-radius: 20px;
  color: var(--text);
  cursor: pointer;
  font-size: 0.85rem;
  padding: 5px 14px;
  text-transform: capitalize;
  transition: border-color 0.15s;
}
.level-btn:hover  { border-color: var(--muted); }
.level-btn.active { border-color: var(--accent); color: var(--accent); }

/* ---------- Stats row ---------- */
.stats {
  color: var(--muted);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.85rem;
  width: 100%;
}
.stats strong { color: var(--text); font-variant-numeric: tabular-nums; }

.peek {
  width: 44px;
  height: 44px;
  border-radius: 6px;
  object-fit: cover;
  border: 2px solid var(--key);
}

.toggle {
  background: var(--key);
  border: 2px solid transparent;
  border-radius: 20px;
  color: var(--text);
  cursor: pointer;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 5px 12px;
  transition: border-color 0.15s, background 0.15s;
}
.toggle:hover { background: var(--key-hover); }
.toggle[aria-pressed="true"] {
  border-color: var(--accent);
  color: var(--accent);
}

/* ---------- Board ---------- */
.board {
  --size: 3;
  position: relative;
  width: min(100%, 420px);
  aspect-ratio: 1;
  background: var(--panel);
  border-radius: 8px;
  padding: 4px;
  touch-action: manipulation;
}

.tile {
  position: absolute;
  width: calc((100% - 8px) / var(--size));
  height: calc((100% - 8px) / var(--size));
  padding: 1.5px;
  cursor: pointer;
  transition: left var(--slide, 0.15s) ease, top var(--slide, 0.15s) ease;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}
.tile-face {
  width: 100%;
  height: 100%;
  border-radius: 4px;
  background-color: var(--key);
  background-repeat: no-repeat;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.25);
  position: relative;
}
.tile:hover .tile-face { filter: brightness(1.08); }

.tile-num {
  position: absolute;
  top: 3px;
  left: 3px;
  min-width: 1.5em;
  padding: 1px 4px;
  border-radius: 6px;
  background: rgba(15, 23, 42, 0.75);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 700;
  text-align: center;
}
.board:not(.show-numbers) .tile-num { display: none; }

/* Solved (or given up): close the gaps so it reads as one picture. */
.board.done .tile { padding: 0; cursor: default; }
.board.done .tile-face { border-radius: 0; box-shadow: none; filter: none; }
.board.done .tile-num { display: none; }
.board.done.won { box-shadow: 0 0 0 3px var(--correct); }

/* ---------- Result banner ---------- */
.result {
  background: var(--panel);
  border-radius: 10px;
  font-size: 1rem;
  font-weight: 600;
  padding: 10px 20px;
  text-align: center;
  white-space: pre-line;
  width: 100%;
}
.result.win  { color: var(--correct); }
.result.loss { color: var(--wrong); }
.result.solving { color: var(--accent); }

/* ---------- Buttons ---------- */
.actions {
  display: flex;
  gap: 10px;
  width: 100%;
}

.new-game {
  background: var(--accent);
  border: none;
  border-radius: 8px;
  color: #0f172a;
  cursor: pointer;
  flex: 1;
  font-size: 1rem;
  font-weight: 700;
  padding: 10px 16px;
}
.new-game:hover  { opacity: 0.9; }
.new-game:active { transform: scale(0.97); }

.give-up {
  background: var(--key);
  border: none;
  border-radius: 8px;
  color: var(--text);
  cursor: pointer;
  font-size: 1rem;
  font-weight: 600;
  padding: 10px 16px;
}
.give-up:hover    { background: var(--key-hover); }
.give-up:disabled { opacity: 0.4; cursor: default; }

/* ---------- Home logo ---------- */
.home-btn {
  display: block;
  margin: 1.5rem auto 0;
  max-width: 220px;
}
.home-btn img { display: block; width: 100%; }
.home-btn:hover { opacity: 0.8; }