/* ============================================================================
   UNIFIED 2D PUZZLE GAME STYLESHEET
   Provides consistent UI/UX across all 2D puzzle games
   Mirrors the 3D unified system adapted for standard DOM layouts
   ============================================================================ */

/* Fonts (Figtree + JetBrains Mono) are loaded globally via tokens.css. */

:root {
  --page-background: #15141a;
  /* ── Color Palette (Crossword Paper, shared with 3D system) ── */
  --color-dark-bg: #15141a;
  --color-secondary-bg: #1b1922;
  --color-tertiary-bg: #232030;
  --color-accent-primary: var(--accent);
  --color-accent-secondary: var(--brand-2);
  --color-accent-tertiary: var(--cat-spatial);
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;
  --color-text-primary: var(--text);
  --color-text-secondary: var(--text-muted);
  --color-text-muted: var(--text-muted);
  --color-border: rgba(71, 85, 105, 0.3);
  --color-border-light: rgba(148, 163, 184, 0.1);

  /* ── Light-mode-swappable component tokens ── */
  --color-card-bg: linear-gradient(180deg, rgba(26, 31, 46, 0.8), rgba(36, 45, 58, 0.6));
  --color-control-btn-bg: linear-gradient(135deg, #334155, #1f2937);
  --color-control-btn-text: white;
  --color-difficulty-bar-bg: rgba(26, 31, 46, 0.6);
  --color-hover-overlay: rgba(255, 255, 255, 0.05);
  --color-tile-bg: rgba(255, 255, 255, 0.03);

  /* ── Typography ── */
  --font-family-base: 'Figtree', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  --font-family-mono: 'JetBrains Mono', 'JetBrains Mono Fallback', 'Fira Code', 'Monaco', monospace;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* ── Spacing ── */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;

  /* ── Border Radius ── */
  --g--radius-xs: 0.25rem;
  --g--radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --g--radius-lg: 0.75rem;
  --g--radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* ── Shadows ── */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --g--shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --g--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.15), 0 1px 3px rgba(0, 0, 0, 0.1);

  /* ── Transitions ── */
  --transition-fast: 100ms ease-in-out;
  --transition-base: 200ms ease-in-out;
  --transition-slow: 300ms ease-in-out;

  /* ── Z-Index Scale ── */
  --z-base: 1;
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 10020;
  --z-modal: 10030;
  --z-toast: 10050;
}

html[data-theme='light'] {
  --page-background: #f5f0eb;
  --color-dark-bg: #f5f0eb;
  --color-secondary-bg: #fdfbf9;
  --color-tertiary-bg: #e8e0d8;
  --color-accent-primary: var(--accent);
  --color-accent-secondary: var(--brand-2);
  --color-accent-tertiary: var(--cat-spatial);
  --color-success: #5a8a4a;
  --color-warning: #c49a4d;
  --color-error: #c44d4d;
  --color-text-primary: var(--text);
  --color-text-secondary: var(--text-muted);
  --color-text-muted: var(--text-muted);
  --color-border: rgba(61, 61, 61, 0.22);
  --color-border-light: rgba(61, 61, 61, 0.16);

  /* ── Light-mode component token overrides ── */
  --color-card-bg: linear-gradient(180deg, rgba(253, 251, 249, 0.97), rgba(245, 240, 235, 0.9));
  --color-control-btn-bg: linear-gradient(135deg, #fdfbf9, #e8e0d8);
  --color-control-btn-text: #3d3d3d;
  --color-difficulty-bar-bg: rgba(245, 240, 235, 0.85);
  --color-hover-overlay: rgba(61, 61, 61, 0.06);
  --color-tile-bg: rgba(61, 61, 61, 0.04);
}

/* ============================================================================
   GLOBAL & BASE STYLES
   ============================================================================ */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-base);
  background: var(--page-background);
  background-attachment: fixed;
  color: var(--color-text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

/* ============================================================================
   PUZZLE PAGE LAYOUT
   ============================================================================ */

.puzzle-page-wrapper {
  max-width: 1280px;
  margin: 0 auto;
  padding: var(--spacing-lg);
}

/* Title area above the main grid */
.puzzle-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  padding: var(--spacing-lg) 0;
}

.puzzle-header h1 {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  margin: 0 0 var(--spacing-xs);
  letter-spacing: -0.02em;
}

.puzzle-header .subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin: 0;
}

/* Main two-column layout */
.puzzle-container {
  display: flex;
  gap: var(--spacing-xl);
  align-items: flex-start;
}

.puzzle-main {
  flex: 1;
  min-width: 0; /* prevent flex overflow */
}

.puzzle-sidebar {
  min-width: 280px;
  width: 25%;
  max-width: 340px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  position: sticky;
  top: 120px; /* below site header */
}

/* ============================================================================
   CARD COMPONENT
   ============================================================================ */

.card {
  background: var(--color-card-bg);
  -webkit-backdrop-filter: blur(12px) saturate(140%);
  backdrop-filter: blur(12px) saturate(140%);
  border: 1px solid var(--color-border);
  border-radius: var(--g--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-card);
  transition: border-color var(--transition-base);
}

.card:hover {
  border-color: rgba(71, 85, 105, 0.5);
}

.card h2,
.card h3 {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: var(--spacing-md);
}

.sidebar-card {
  background: var(--color-card-bg);
  -webkit-backdrop-filter: blur(12px) saturate(140%);
  backdrop-filter: blur(12px) saturate(140%);
  border: 1px solid var(--color-border);
  border-radius: var(--g--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-card);
  transition: border-color var(--transition-base);
}

.sidebar-card:hover {
  border-color: rgba(71, 85, 105, 0.5);
}

.sidebar-card h2,
.sidebar-card h3 {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: var(--spacing-md);
}

/* ============================================================================
   GAME STATS PANEL
   ============================================================================ */

.game-stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-sm);
}

.game-stat-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-sm) 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.game-stat-row:not(:last-child) {
  border-bottom: 1px solid var(--color-border-light);
}

.game-stats-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-sm) 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.game-stats-item:not(:last-child) {
  border-bottom: 1px solid var(--color-border-light);
}

.stat-label {
  font-weight: var(--font-weight-medium);
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
}

.stat-value {
  color: var(--color-accent-primary);
  font-weight: var(--font-weight-semibold);
  font-family: var(--font-family-mono);
  font-size: var(--font-size-sm);
}

/* Stat items as compact tiles */
.stats-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
  gap: var(--spacing-sm);
}

.stat-tile {
  text-align: center;
  padding: var(--spacing-sm);
  background: var(--color-tile-bg);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-light);
}

.stat-tile .stat-label {
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 2px;
  display: block;
}

.stat-tile .stat-value {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  display: block;
}

/* ============================================================================
   BUTTON STYLES
   ============================================================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  font-family: var(--font-family-base);
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  white-space: nowrap;
  -webkit-user-select: none;
  user-select: none;
  text-decoration: none;
  gap: var(--spacing-sm);
  line-height: 1.4;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn:focus-visible {
  outline: 2px solid var(--color-accent-primary);
  outline-offset: 2px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-accent-primary), #2563eb);
  color: white;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(59, 130, 246, 0.4);
}

.btn-primary:active:not(:disabled) {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--color-tertiary-bg);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--color-secondary-bg);
  border-color: var(--color-accent-primary);
}

.btn-success {
  background: linear-gradient(135deg, var(--color-success), #059669);
  color: white;
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

.btn-success:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(16, 185, 129, 0.4);
}

.btn-danger {
  background: linear-gradient(135deg, var(--color-error), #dc2626);
  color: white;
  box-shadow: 0 4px 12px rgba(239, 68, 68, 0.3);
}

.btn-danger:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(239, 68, 68, 0.4);
}

.btn-warning {
  background: linear-gradient(135deg, var(--color-warning), #d97706);
  color: white;
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.btn-warning:hover:not(:disabled) {
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
}

.btn-ghost:hover:not(:disabled) {
  background: var(--color-hover-overlay);
  color: var(--color-text-primary);
  border-color: var(--color-text-muted);
}

.btn-small {
  padding: var(--spacing-xs) var(--spacing-sm);
  font-size: var(--font-size-xs);
}

.btn-large {
  padding: var(--spacing-md) var(--spacing-lg);
  font-size: var(--font-size-base);
}

.btn-block {
  width: 100%;
}

/* Sidebar control buttons stacked */
.control-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  font-family: var(--font-family-base);
  border: none;
  background: var(--color-control-btn-bg);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  color: var(--color-control-btn-text);
  margin-bottom: var(--spacing-sm);
  gap: var(--spacing-sm);
  line-height: 1.4;
}

.control-btn:last-child {
  margin-bottom: 0;
}

.control-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.control-btn:focus-visible {
  outline: 2px solid var(--color-accent-primary);
  outline-offset: 2px;
}

.control-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  filter: brightness(1.1);
}

.control-btn:active:not(:disabled) {
  transform: translateY(0);
}

.control-btn-new-game,
.control-button.control-btn-new-game,
.control-btn-hint,
.control-button.control-btn-hint,
.control-btn-preview,
.control-button.control-btn-preview {
  background: linear-gradient(135deg, var(--color-accent-primary), var(--color-accent-secondary)) !important;
  color: white !important;
  border: none !important;
}

/* Unified control-card button scheme across 2D puzzles */
.puzzle-sidebar .card .control-btn,
.puzzle-sidebar .sidebar-card .control-btn {
  background: var(--color-control-btn-bg) !important;
  color: var(--color-control-btn-text) !important;
  border: 1px solid var(--color-border) !important;
}

.puzzle-sidebar .card .control-btn.control-btn-new-game,
.puzzle-sidebar .sidebar-card .control-btn.control-btn-new-game,
.puzzle-sidebar .card .control-btn.control-btn-hint,
.puzzle-sidebar .sidebar-card .control-btn.control-btn-hint,
.puzzle-sidebar .card .control-btn.control-btn-preview,
.puzzle-sidebar .sidebar-card .control-btn.control-btn-preview,
.puzzle-sidebar .card #hint-btn.control-btn,
.puzzle-sidebar .sidebar-card #hint-btn.control-btn,
.puzzle-sidebar .card #get-hint-btn.control-btn,
.puzzle-sidebar .sidebar-card #get-hint-btn.control-btn,
.puzzle-sidebar .card #get-hint.control-btn,
.puzzle-sidebar .sidebar-card #get-hint.control-btn,
.puzzle-sidebar .card #previewBtn.control-btn,
.puzzle-sidebar .sidebar-card #previewBtn.control-btn {
  background: linear-gradient(135deg, var(--color-accent-primary), var(--color-accent-secondary)) !important;
  color: white !important;
  border: none !important;
}

/* ============================================================================
   FORM CONTROLS
   ============================================================================ */

.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-sm);
}

.form-control,
select,
input[type="text"],
input[type="number"] {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-tertiary-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
  font-size: var(--font-size-sm);
  font-family: var(--font-family-base);
  transition: all var(--transition-base);
}

.form-control:focus,
select:focus,
input[type="text"]:focus,
input[type="number"]:focus {
  outline: none;
  border-color: var(--color-accent-primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right var(--spacing-sm) center;
  background-size: 1.2em 1.2em;
  padding-right: 2.5em;
}

/* ============================================================================
   DIFFICULTY SELECTOR
   ============================================================================ */

.difficulty-selector {
  display: flex;
  gap: var(--spacing-sm);
  margin: var(--spacing-md) 0;
}

.difficulty-btn {
  flex: 1;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  font-family: var(--font-family-base);
  cursor: pointer;
  transition: all var(--transition-base);
  text-transform: capitalize;
}

.difficulty-btn:hover {
  border-color: var(--color-accent-primary);
  color: var(--color-accent-primary);
}

.difficulty-btn.active {
  background: var(--color-accent-primary);
  border-color: var(--color-accent-primary);
  color: white;
}

.difficulty-btn.active.easy,
.difficulty-btn.easy:hover { border-color: var(--color-success); }
.difficulty-btn.active.easy { background: var(--color-success); }

.difficulty-btn.active.medium,
.difficulty-btn.medium:hover { border-color: var(--color-warning); }
.difficulty-btn.active.medium { background: var(--color-warning); }

.difficulty-btn.active.hard,
.difficulty-btn.hard:hover { border-color: var(--color-error); }
.difficulty-btn.active.hard { background: var(--color-error); }

.difficulty-btn.active.expert,
.difficulty-btn.expert:hover { border-color: var(--color-accent-tertiary); }
.difficulty-btn.active.expert { background: var(--color-accent-tertiary); }

/* Inline difficulty bar at top of page */
.difficulty-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-md);
  padding: var(--spacing-md) var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  background: var(--color-difficulty-bar-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--g--radius-lg);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.difficulty-bar label {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
}

.difficulty-bar select {
  width: auto;
  min-width: 160px;
}

/* ============================================================================
   PROGRESS BAR
   ============================================================================ */

.progress-bar-container {
  width: 100%;
  height: 6px;
  background: var(--color-tertiary-bg);
  border-radius: var(--radius-full);
  overflow: hidden;
  border: 1px solid var(--color-border-light);
}

.progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--color-accent-primary), var(--color-accent-secondary));
  border-radius: var(--radius-full);
  transition: width var(--transition-slow) ease-out;
  width: 0%;
}

/* ============================================================================
   STATUS/ALERT MESSAGES (Toast style)
   ============================================================================ */

.alert {
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  border-left: 4px solid;
  font-size: var(--font-size-sm);
  margin-bottom: var(--spacing-md);
}

.alert-success {
  background: rgba(16, 185, 129, 0.1);
  border-color: var(--color-success);
  color: #6ee7b7;
}

.alert-warning {
  background: rgba(245, 158, 11, 0.1);
  border-color: var(--color-warning);
  color: #fcd34d;
}

.alert-error {
  background: rgba(239, 68, 68, 0.1);
  border-color: var(--color-error);
  color: #fca5a5;
}

.alert-info {
  background: rgba(59, 130, 246, 0.1);
  border-color: var(--color-accent-primary);
  color: #93c5fd;
}

/* Toast notifications (fixed position) */
.game-toast {
  position: fixed;
  top: 80px;
  left: 50%;
  transform: translateX(-50%) translateY(-20px);
  padding: var(--spacing-md) var(--spacing-xl);
  border-radius: var(--g--radius-lg);
  color: white;
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-sm);
  z-index: var(--z-toast);
  opacity: 0;
  transition: all var(--transition-slow);
  pointer-events: none;
  box-shadow: var(--g--shadow-lg);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  max-width: 500px;
  text-align: center;
}

.game-toast.visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.game-toast.success { background: rgba(16, 185, 129, 0.9); }
.game-toast.error   { background: rgba(239, 68, 68, 0.9); }
.game-toast.info    { background: rgba(59, 130, 246, 0.9); }
.game-toast.warning { background: rgba(245, 158, 11, 0.9); }

/* ============================================================================
   MESSAGE AREA (inline message below puzzle)
   ============================================================================ */

.message-area {
  margin-top: var(--spacing-lg);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  text-align: center;
  background: var(--color-tertiary-bg);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border-light);
}

.message-area.success {
  background: rgba(16, 185, 129, 0.1);
  color: #6ee7b7;
  border-color: rgba(16, 185, 129, 0.3);
}

.message-area.error {
  background: rgba(239, 68, 68, 0.1);
  color: #fca5a5;
  border-color: rgba(239, 68, 68, 0.3);
}

.message-area.warning {
  background: rgba(245, 158, 11, 0.1);
  color: #fcd34d;
  border-color: rgba(245, 158, 11, 0.3);
}

.message-area.info {
  background: rgba(59, 130, 246, 0.1);
  color: #93c5fd;
  border-color: rgba(59, 130, 246, 0.3);
}

/* ============================================================================
   MODAL / DIALOG
   ============================================================================ */

.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal-backdrop);
  -webkit-backdrop-filter: blur(4px);
  backdrop-filter: blur(4px);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal-dialog {
  background: var(--color-secondary-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--g--radius-xl);
  padding: var(--spacing-xl);
  max-width: 500px;
  width: 90%;
  box-shadow: var(--shadow-xl);
  z-index: var(--z-modal);
  animation: modalSlideIn var(--transition-slow) ease-out;
  position: relative;
}

.modal-overlay.active .modal-dialog {
  transform: scale(1);
}

.modal-header {
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-md);
  border-bottom: 1px solid var(--color-border);
}

.modal-header h2 {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  text-transform: none;
  letter-spacing: normal;
  color: var(--color-text-primary);
  margin: 0;
}

.modal-body {
  margin-bottom: var(--spacing-lg);
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.modal-footer {
  display: flex;
  gap: var(--spacing-md);
  justify-content: flex-end;
}

.modal-close {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  background: none;
  border: none;
  color: var(--color-text-muted);
  cursor: pointer;
  font-size: var(--font-size-lg);
  padding: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--g--radius-sm);
  transition: all var(--transition-base);
}

.modal-close:hover {
  color: var(--color-text-primary);
  background: var(--color-hover-overlay);
}

/* ============================================================================
   BADGES & LABELS
   ============================================================================ */

.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-primary {
  background: rgba(59, 130, 246, 0.15);
  color: #93c5fd;
}

.badge-success {
  background: rgba(16, 185, 129, 0.15);
  color: #6ee7b7;
}

.badge-warning {
  background: rgba(245, 158, 11, 0.15);
  color: #fcd34d;
}

.badge-danger {
  background: rgba(239, 68, 68, 0.15);
  color: #fca5a5;
}

/* ============================================================================
   HOW TO PLAY SECTION
   ============================================================================ */

.how-to-play p,
.how-to-play li {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  line-height: 1.7;
  margin: 0;
}

.how-to-play ul {
  padding-left: var(--spacing-md);
  margin-top: var(--spacing-sm);
}

.how-to-play li {
  margin-bottom: var(--spacing-xs);
}

.how-to-play kbd {
  background: var(--color-tertiary-bg);
  padding: 1px 6px;
  border-radius: 3px;
  font-family: var(--font-family-mono);
  font-size: 0.7rem;
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
}

/* ============================================================================
   VICTORY / COMPLETION OVERLAY
   ============================================================================ */

.victory-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(15, 20, 25, 0.9);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal-backdrop);
  opacity: 0;
  transition: opacity var(--transition-slow);
  pointer-events: none;
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.victory-overlay.show {
  opacity: 1;
  pointer-events: auto;
}

.victory-content {
  background: var(--color-secondary-bg);
  border: 1px solid var(--color-border);
  padding: var(--spacing-2xl);
  border-radius: var(--g--radius-xl);
  text-align: center;
  max-width: 440px;
  width: 90%;
  box-shadow: var(--shadow-xl);
  animation: modalSlideIn var(--transition-slow) ease-out;
}

.victory-content h2 {
  font-size: var(--font-size-2xl);
  color: var(--color-success);
  margin-bottom: var(--spacing-md);
  text-transform: none;
  letter-spacing: normal;
}

.victory-content p {
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xl);
  font-size: var(--font-size-sm);
}

.victory-content .btn {
  margin: 0 var(--spacing-sm);
}

/* Victory stats cards */
.victory-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-xl);
}

.victory-stat {
  background: var(--color-tile-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
}

.victory-stat .stat-label {
  display: block;
  font-size: var(--font-size-xs);
  margin-bottom: var(--spacing-xs);
}

.victory-stat .stat-value {
  display: block;
  font-size: var(--font-size-xl);
}

/* ============================================================================
   ANIMATIONS
   ============================================================================ */

@keyframes modalSlideIn {
  from {
    opacity: 0;
    transform: translateY(-20px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes fadeOut {
  from { opacity: 1; }
  to   { opacity: 0; }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.6; }
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25%      { transform: translateX(-5px); }
  75%      { transform: translateX(5px); }
}

/* ============================================================================
   UTILITY CLASSES
   ============================================================================ */

.text-center  { text-align: center; }
.text-left    { text-align: left; }
.text-right   { text-align: right; }
.hidden       { display: none !important; }
.invisible    { visibility: hidden; }
.flex-center  { display: flex; align-items: center; justify-content: center; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }
.mt-sm  { margin-top: var(--spacing-sm); }
.mt-md  { margin-top: var(--spacing-md); }
.mt-lg  { margin-top: var(--spacing-lg); }
.mb-sm  { margin-bottom: var(--spacing-sm); }
.mb-md  { margin-bottom: var(--spacing-md); }
.mb-lg  { margin-bottom: var(--spacing-lg); }

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

/* ============================================================================
   RESPONSIVE DESIGN
   ============================================================================ */

@media (max-width: 960px) {
  .puzzle-container {
    flex-direction: column;
  }

  .puzzle-sidebar {
    width: 100%;
    position: static;
    flex-direction: row;
    flex-wrap: wrap;
  }

  .puzzle-sidebar > .card,
  .puzzle-sidebar > .sidebar-card,
  .puzzle-sidebar > div {
    flex: 1;
    min-width: 250px;
  }

  .puzzle-page-wrapper {
    padding: var(--spacing-md);
  }
}

/* ============================================================================
   LIGHT MODE COMPONENT OVERRIDES
   ============================================================================ */

html[data-theme='light'] .alert-success { color: #5a8a4a; }
html[data-theme='light'] .alert-warning { color: #9a7a2e; }
html[data-theme='light'] .alert-error   { color: #c44d4d; }
html[data-theme='light'] .alert-info    { color: #4a7a9b; }

html[data-theme='light'] .message-area.success { color: #5a8a4a; }
html[data-theme='light'] .message-area.warning { color: #9a7a2e; }
html[data-theme='light'] .message-area.error   { color: #c44d4d; }
html[data-theme='light'] .message-area.info    { color: #4a7a9b; }

html[data-theme='light'] .badge-primary { background: rgba(139, 58, 58, 0.12); color: #8b3a3a; }
html[data-theme='light'] .badge-success { background: rgba(90, 138, 74, 0.14); color: #5a8a4a; }
html[data-theme='light'] .badge-warning { background: rgba(196, 154, 77, 0.15); color: #9a7a2e; }
html[data-theme='light'] .badge-danger  { background: rgba(196, 77, 77, 0.14); color: #c44d4d; }

html[data-theme='light'] .card:hover,
html[data-theme='light'] .sidebar-card:hover {
  border-color: rgba(139, 58, 58, 0.4);
}

@media (max-width: 640px) {
  .puzzle-header h1 {
    font-size: var(--font-size-2xl);
  }

  .puzzle-sidebar {
    flex-direction: column;
  }

  .puzzle-sidebar > .card,
  .puzzle-sidebar > .sidebar-card,
  .puzzle-sidebar > div {
    min-width: auto;
  }

  .difficulty-selector {
    flex-direction: column;
  }

  .difficulty-bar {
    flex-direction: column;
    gap: var(--spacing-sm);
  }

  .victory-content {
    padding: var(--spacing-xl);
  }

  .modal-dialog {
    width: 95%;
    padding: var(--spacing-lg);
  }
}

@media (max-width: 360px) {
  .puzzle-page-wrapper {
    padding: var(--spacing-sm);
  }

  .puzzle-header {
    padding: var(--spacing-sm) 0;
    margin-bottom: var(--spacing-md);
  }

  .puzzle-header h1 {
    font-size: var(--font-size-xl);
  }

  .btn {
    padding: 0.35rem 0.55rem;
    font-size: 0.72rem;
  }

  .modal-dialog {
    width: 100%;
    border-radius: 0;
    padding: var(--spacing-md);
  }
}

/* Touch-optimized: increase tap targets to minimum 44x44px */
@media (hover: none) and (pointer: coarse) {
  .btn,
  .control-btn,
  .classic-btn,
  .modal-close,
  .nav-link,
  button[type="submit"],
  button[class*="btn"] {
    min-height: 44px;
    min-width: 44px;
    padding: var(--spacing-sm) var(--spacing-md);
  }

  .modal-close {
    width: 44px;
    height: 44px;
  }
}