/* Holi Sudoku – base layout, palette & grid (Phase 1) + Phase 6 polish */

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
  overflow-y: auto;
}

/* 1.1 – 9-color Holi palette (maximally distinct hues & contrast) */
:root {
  --holi-1: #ff0b0b;   /* red – deep red */
  --holi-2: #0164bb;   /* blue */
  --holi-3: #43a047;   /* green */
  --holi-4: #fdd835;   /* yellow */
  --holi-5: #ec407a;   /* pink – cooler, more magenta */
  --holi-6: #f57c00;   /* orange */
  --holi-7: #00ff1a;   /* purple */
  --holi-8: #02d1ec;   /* cyan */
  --holi-9: #880e4f;   /* magenta / deep fuchsia */
  --holi-bg: #fff8e1;
  --holi-surface: #ffffff;
  --holi-text: #1a1a1a;
  --holi-cell-empty: #f5f5f5;
  --holi-border: #e0e0e0;
  --holi-box-border: #6d6d6d;
  --holi-box-tint: rgba(0, 0, 0, 0.03);
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;
  font-size: 16px;
  color: var(--holi-text);
  /* Phase 6: Holi-themed gradient background */
  background: linear-gradient(160deg, #fff8e1 0%, #ffe0b2 25%, #ffecb3 50%, #e8f5e9 75%, #e3f2fd 100%);
  background-attachment: fixed;
  /* Respect safe-area insets (notch, home indicator, etc.) */
  padding-top: env(safe-area-inset-top);
  padding-right: env(safe-area-inset-right);
  padding-bottom: env(safe-area-inset-bottom);
  padding-left: env(safe-area-inset-left);
}

#app {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  padding-top: max(1rem, env(safe-area-inset-top));
  padding-bottom: max(1rem, env(safe-area-inset-bottom));
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
  overflow: auto;
}

/* Phase 6: festive title */
.app-title {
  margin: 0 0 0.75rem;
  font-size: clamp(1.5rem, 5vw, 2rem);
  font-weight: 800;
  letter-spacing: 0.02em;
  background: linear-gradient(90deg, var(--holi-1), var(--holi-5), var(--holi-7), var(--holi-6));
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.btn-rules {
  font-size: 0.875rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  margin-bottom: 0.5rem;
  border-radius: 8px;
  border: 2px solid var(--holi-border);
  background: var(--holi-surface);
  color: var(--holi-text);
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}
.btn-rules:hover,
.btn-rules:focus {
  transform: scale(1.02);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}
.btn-rules:active {
  transform: scale(0.98);
}

.stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  margin-bottom: 0.5rem;
  min-height: 1.5rem;
}

.timer {
  font-variant-numeric: tabular-nums;
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--holi-text);
}

.completeness {
  font-variant-numeric: tabular-nums;
  font-size: 1rem;
  font-weight: 600;
  color: var(--holi-text);
  opacity: 0.85;
}

.mistakes {
  font-variant-numeric: tabular-nums;
  font-size: 1rem;
  font-weight: 600;
  color: var(--holi-text);
  opacity: 0.85;
}

.mistakes[aria-live] {
  min-width: 3.5em;
}

.btn-sound {
  font-size: 0.875rem;
  font-weight: 600;
  padding: 0.25rem 0.5rem;
  border-radius: 6px;
  border: 1px solid var(--holi-border);
  background: var(--holi-surface);
  color: var(--holi-text);
  cursor: pointer;
  min-height: 2rem;
}

.btn-sound:hover {
  background: var(--holi-cell-empty);
}

.btn-sound.btn-sound--muted {
  opacity: 0.7;
}

/* 1.2 – Touch targets ≥ 44×44px for cells */
/* 1.3 – 9×9 grid layout */
.board {
  display: grid;
  grid-template-columns: repeat(9, 1fr);
  grid-template-rows: repeat(9, 1fr);
  gap: 0;
  /* Fit within viewport so board is fully visible; cap size on large screens */
  width: min(90vmin, 85vh, 400px);
  aspect-ratio: 1;
  flex-shrink: 0;
  background: var(--holi-box-border);
  border: 3px solid var(--holi-box-border);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08), 0 0 0 1px rgba(255, 255, 255, 0.5) inset;
}

.cell {
  min-width: 0;
  min-height: 0;
  aspect-ratio: 1;
  background: var(--holi-cell-empty);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 0;
  border-right: 1px solid var(--holi-border);
  border-bottom: 1px solid var(--holi-border);
}

/* Thicker, darker borders between 3×3 boxes so they are clearly distinguishable */
.cell[data-col="2"],
.cell[data-col="5"] {
  border-right-width: 4px;
  border-right-color: var(--holi-box-border);
}

.cell[data-row="2"],
.cell[data-row="5"] {
  border-bottom-width: 4px;
  border-bottom-color: var(--holi-box-border);
}

.cell[data-col="8"] {
  border-right: none;
}

.cell[data-row="8"] {
  border-bottom: none;
}

/* Alternating subtle tint per 3×3 box (boxes 1, 3, 5, 7 get a light shade) */
.cell[data-box="1"],
.cell[data-box="3"],
.cell[data-box="5"],
.cell[data-box="7"] {
  background: color-mix(in srgb, var(--holi-cell-empty) 92%, var(--holi-box-tint));
}

/* Phase 2: selection and highlight */
.cell--selected {
  box-shadow: inset 0 0 0 3px var(--holi-text);
  z-index: 1;
}

/* Phase 3: duplicate conflict styling */
.cell--conflict {
  box-shadow: inset 0 0 0 3px var(--holi-1);
  z-index: 1;
}
.cell--conflict.cell--selected {
  box-shadow: inset 0 0 0 3px var(--holi-text), inset 0 0 0 6px var(--holi-1);
}

/* Wrong value (doesn't match solution); distinct from conflict (duplicate in row/col/box) */
.cell--incorrect {
  box-shadow: inset 0 0 0 3px #b71c1c;
  z-index: 1;
  filter: brightness(0.92) saturate(1.1);
}
.cell--incorrect.cell--selected {
  box-shadow: inset 0 0 0 3px var(--holi-text), inset 0 0 0 6px #b71c1c;
}

/* Color palette (Phase 2) */
.palette {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.5rem;
  margin-top: 1rem;
  padding: 0.75rem;
}

.palette-swatch {
  width: 44px;
  height: 44px;
  min-width: 44px;
  min-height: 44px;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.palette-swatch:hover,
.palette-swatch:focus {
  transform: scale(1.08);
  box-shadow: 0 2px 6px rgba(0,0,0,0.25);
}

.palette-swatch:active {
  transform: scale(0.98);
}

.palette-swatch--active {
  box-shadow: 0 0 0 3px var(--holi-text);
  outline: none;
}

/* Tick for completed colors in palette */
.palette-swatch--completed {
  position: relative;
}
.palette-swatch--completed::after {
  content: "✓";
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: bold;
  color: rgba(255, 255, 255, 0.95);
  text-shadow: 0 0 2px rgba(0, 0, 0, 0.6), 0 1px 2px rgba(0, 0, 0, 0.5);
  pointer-events: none;
}

.btn-clear-cell {
  min-height: 44px;
  margin-top: 0.75rem;
  padding: 0.5rem 1.25rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--holi-text);
  background: var(--holi-surface);
  border: 2px solid var(--holi-box-border);
  border-radius: 12px;
  cursor: pointer;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.08);
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}
.btn-clear-cell:hover,
.btn-clear-cell:focus {
  transform: scale(1.02);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.12);
  background: var(--holi-cell-empty);
}
.btn-clear-cell:active {
  transform: scale(0.98);
}
.btn-clear-cell:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.btn-new-puzzle {
  min-height: 44px;
  margin-top: 1rem;
  padding: 0.5rem 1.25rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--holi-surface);
  background: linear-gradient(135deg, var(--holi-6), var(--holi-4));
  border: none;
  border-radius: 12px;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(239, 108, 0, 0.35);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.btn-new-puzzle:hover,
.btn-new-puzzle:focus {
  transform: scale(1.03);
  box-shadow: 0 4px 12px rgba(239, 108, 0, 0.45);
}
.btn-new-puzzle:active {
  transform: scale(0.98);
}

/* Phase 3 + 6: win message (modal) – Holi-style, safe-area */
.win-message {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: max(1rem, env(safe-area-inset-top)) max(1rem, env(safe-area-inset-right)) max(1rem, env(safe-area-inset-bottom)) max(1rem, env(safe-area-inset-left));
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(4px);
  z-index: 100;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}
.win-message.win-message--visible {
  opacity: 1;
  visibility: visible;
}
.win-message__content {
  background: var(--holi-surface);
  padding: 1.5rem;
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2), 0 0 0 4px var(--holi-4);
  text-align: center;
  max-width: 320px;
  border: 3px solid var(--holi-5);
}
.win-message__title {
  margin: 0 0 0.5rem;
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--holi-text);
}
.win-message__text {
  margin: 0 0 1rem;
  font-size: 1rem;
  color: var(--holi-text);
}
.win-message__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-top: 1rem;
}
.win-message__btn {
  min-width: 44px;
  min-height: 44px;
  padding: 0.5rem 1rem;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.win-message__btn--primary {
  color: var(--holi-surface);
  background: linear-gradient(135deg, var(--holi-6), var(--holi-5));
  box-shadow: 0 2px 8px rgba(236, 64, 122, 0.4);
}
.win-message__btn--primary:hover,
.win-message__btn--primary:focus {
  transform: scale(1.02);
  box-shadow: 0 4px 12px rgba(236, 64, 122, 0.5);
}
.win-message__btn--secondary {
  color: var(--holi-text);
  background: var(--holi-cell-empty);
  border: 2px solid var(--holi-border);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}
.win-message__btn--secondary:hover,
.win-message__btn--secondary:focus {
  background: var(--holi-border);
  transform: scale(1.02);
}
.win-message__btn:active {
  transform: scale(0.98);
}

/* Game over overlay – same pattern as win message */
.game-over-message {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: max(1rem, env(safe-area-inset-top)) max(1rem, env(safe-area-inset-right)) max(1rem, env(safe-area-inset-bottom)) max(1rem, env(safe-area-inset-left));
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  z-index: 100;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}
.game-over-message.game-over-message--visible {
  opacity: 1;
  visibility: visible;
}
.game-over-message__content {
  background: var(--holi-surface);
  padding: 1.5rem;
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.25), 0 0 0 4px var(--holi-1);
  text-align: center;
  max-width: 320px;
  border: 3px solid var(--holi-1);
}
.game-over-message__title {
  margin: 0 0 0.5rem;
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--holi-text);
}
.game-over-message__text {
  margin: 0 0 1rem;
  font-size: 1rem;
  color: var(--holi-text);
}
.game-over-message__btn {
  min-width: 44px;
  min-height: 44px;
  padding: 0.5rem 1rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--holi-surface);
  background: linear-gradient(135deg, var(--holi-6), var(--holi-5));
  border: none;
  border-radius: 8px;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(236, 64, 122, 0.4);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.game-over-message__btn:hover,
.game-over-message__btn:focus {
  transform: scale(1.02);
  box-shadow: 0 4px 12px rgba(236, 64, 122, 0.5);
}
.game-over-message__btn:active {
  transform: scale(0.98);
}

/* Rules modal – Hindi text, left-aligned list */
.rules-modal {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: max(1rem, env(safe-area-inset-top)) max(1rem, env(safe-area-inset-right)) max(1rem, env(safe-area-inset-bottom)) max(1rem, env(safe-area-inset-left));
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(4px);
  z-index: 100;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}
.rules-modal.rules-modal--visible {
  opacity: 1;
  visibility: visible;
}
.rules-modal__content {
  background: var(--holi-surface);
  padding: 1.5rem;
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2), 0 0 0 4px var(--holi-4);
  max-width: 420px;
  max-height: 85vh;
  overflow-y: auto;
  border: 3px solid var(--holi-3);
}
.rules-modal__title {
  margin: 0 0 1rem;
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--holi-text);
  text-align: center;
}
.rules-modal__body {
  font-size: 0.95rem;
  color: var(--holi-text);
  text-align: left;
  line-height: 1.5;
}
.rules-modal__body p {
  margin: 0 0 0.75rem;
}
.rules-modal__body ul {
  margin: 0 0 1rem;
  padding-left: 1.25rem;
}
.rules-modal__body li {
  margin-bottom: 0.5rem;
}
.rules-modal__close {
  display: block;
  margin: 0 auto;
  min-width: 44px;
  min-height: 44px;
  padding: 0.5rem 1.25rem;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  color: var(--holi-surface);
  background: linear-gradient(135deg, var(--holi-6), var(--holi-5));
  box-shadow: 0 2px 8px rgba(236, 64, 122, 0.4);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.rules-modal__close:hover,
.rules-modal__close:focus {
  transform: scale(1.02);
  box-shadow: 0 4px 12px rgba(236, 64, 122, 0.5);
}
.rules-modal__close:active {
  transform: scale(0.98);
}

/* Phase 6.4 & 6.5: safe-area already on body/app/modal; desktop pass */
@media (min-width: 600px) {
  #app {
    padding: 1.5rem;
  }
  .board {
    width: min(90vmin, 65vh, 420px);
  }
  .app-title {
    margin-bottom: 1rem;
  }
  .palette {
    margin-top: 1.25rem;
    padding: 1rem;
  }
  .btn-new-puzzle {
    margin-top: 1.25rem;
    padding: 0.6rem 1.5rem;
  }
}

@media (min-width: 900px) {
  .board {
    width: min(85vmin, 480px);
  }
}