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

@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:wght@400;700&family=Source+Sans+3:wght@300;400;600&display=swap');

:root {
  --bg: #f0ede8;
  --surface: #faf8f5;
  --ink: #1a1814;
  --ink-muted: #8a8680;
  --accent: #7a1f2e;
  --accent-light: #f5e8e4;
  --given: #1a1814;
  --player: #2484c6;
  --highlight: #e8e4dc;
  --match: #ddd8cc;
  --error: #fce8e4;
  --border-thin: #ccc8c0;
  --border-thick: #1a1814;
  --navy: #0d2b55;
}

body {
  background: var(--bg);
  font-family: 'Source Sans 3', sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  gap: 1.5rem;
  padding-top: 80px;
}

header { text-align: center; }

h1 {
  font-family:'Playfair Display', serif;
  font-weight: 300;
  font-size: clamp(1.6rem, 5vw, 2.8rem);
  letter-spacing: 0.18em;
  color: var(--ink);
  text-transform: uppercase;
}

.subtitle {
  font-size: clamp(0.7rem, 2vw, 0.85rem);
  color: var(--ink-muted);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-top: 0.2rem;
}

.btn {
  font-family: 'Playfair Display', serif;
  font-size: clamp(0.65rem, 1.8vw, 0.8rem);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0.5em 1.2em;
  border: 1.5px solid var(--ink);
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  border-radius: 2px;
}

.btn:hover { background: var(--ink); color: var(--surface); }

.btn.accent {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.btn.accent:hover { 
  background: #a33a22; border-color: #a33a22;
  transform: translateY(-2px);
 }

.difficulty {
  display: flex;
  gap: 0.3rem;
  background: var(--surface);
  border: 1.5px solid var(--border-thin);
  border-radius: 2px;
  padding: 0.2rem;
}

.diff-btn {
  font-family: 'Playfair Display', serif;
  font-size: clamp(0.6rem, 1.6vw, 0.72rem);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.35em 0.9em;
  border: none;
  background: transparent;
  color: var(--ink-muted);
  cursor: pointer;
  border-radius: 1px;
  transition: background 0.15s, color 0.15s;
}

.diff-btn.active {
  background: var(--ink);
  color: var(--surface);
}

.grid-wrap {
  width: min(92vw, 92vh, 520px);
  aspect-ratio: 1;
}

.grid {
  width: 100%;
  height: 100%;
  display: grid;
  grid-template-columns: repeat(9, 1fr);
  grid-template-rows: repeat(9, 1fr);
  border: 2.5px solid var(--border-thick);
  background: var(--border-thick);
  gap: 1px;
  border-radius: 3px;
  overflow: hidden;
  box-shadow: 6px 6px 0 #ccc8c0;
}

.cell {
  background: var(--surface);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  cursor: pointer;
  transition: background 0.1s;
}

.cell[data-col="2"], .cell[data-col="5"] { border-right: 2px solid var(--border-thick); }
.cell[data-row="2"], .cell[data-row="5"] { border-bottom: 2px solid var(--border-thick); }

.cell.highlighted { background: var(--highlight); }
.cell.matched     { background: var(--match); }
.cell.selected    { background: var(--accent-light) !important; }
.cell.error       { background: var(--error) !important; }

.cell input {
  width: 100%;
  height: 100%;
  border: none;
  background: transparent;
  text-align: center;
  font-family: 'DM Mono', monospace;
  font-size: clamp(0.9rem, 3.5vmin, 1.6rem);
  font-weight: 400;
  color: var(--player);
  caret-color: transparent;
  cursor: pointer;
  outline: none;
  -webkit-appearance: none;
  padding: 0;
}

.cell input::-webkit-outer-spin-button,
.cell input::-webkit-inner-spin-button { -webkit-appearance: none; }

.cell.given input {
  color: var(--given);
  font-weight: 500;
  pointer-events: none;
}

.notes {
  position: absolute;
  inset: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(3, 1fr);
  padding: 1px;
  pointer-events: none;
}

.note {
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'DM Mono', monospace;
  font-size: clamp(0.35rem, 1vmin, 0.55rem);
  color: var(--ink-muted);
  line-height: 1;
}

.numpad {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  justify-content: center;
}

.num-btn {
  font-family: 'Playfair Display', serif;
  font-size: clamp(0.9rem, 3vw, 1.2rem);
  font-weight: 400;
  width: clamp(2.2rem, 7vw, 3rem);
  height: clamp(2.2rem, 7vw, 3rem);
  border: 1.5px solid var(--border-thin);
  background: var(--surface);
  color: var(--ink);
  cursor: pointer;
  border-radius: 2px;
  transition: background 0.12s, border-color 0.12s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.num-btn:hover { background: var(--highlight); border-color: var(--ink); }
.num-btn.erase { font-size: clamp(0.7rem, 2vw, 0.9rem); letter-spacing: 0.05em; }

.mode-toggle {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: clamp(0.65rem, 1.8vw, 0.78rem);
  color: var(--ink-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  user-select: none;
}

.toggle-track {
  width: 2.4em;
  height: 1.2em;
  background: var(--border-thin);
  border-radius: 99px;
  position: relative;
  transition: background 0.2s;
}

.toggle-track.on { background: var(--accent); }

.toggle-knob {
  position: absolute;
  top: 0.15em;
  left: 0.15em;
  width: 0.9em;
  height: 0.9em;
  background: white;
  border-radius: 50%;
  transition: transform 0.2s;
}

.toggle-track.on .toggle-knob { transform: translateX(1.2em); }

.status {
  font-family: 'Playfair Display', serif;
  font-size: clamp(0.65rem, 1.8vw, 0.78rem);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-muted);
  min-height: 1.2em;
  text-align: center;
}

.status.win {
  color: var(--olive-leaf);
  font-weight: 500;
  animation: pop 0.3s ease;
}

@keyframes pop {
  0%   { transform: scale(1); }
  50%  { transform: scale(1.08); }
  100% { transform: scale(1); }
}

.timer {
  font-family: 'Playfair Display', serif;
  font-size: clamp(0.75rem, 2vw, 0.9rem);
  color: var(--ink-muted);
  letter-spacing: 0.12em;
}

.top-row {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  flex-wrap: wrap;
  justify-content: center;
}