/* ============================================
   CSS VARIABLES
   ============================================ */
:root {
  /* Main colors */
  --kn-green: #2F5233;
  --kn-green-border: #1B5E20;
  --kn-gold: #246EB9;
  --kn-gold-border: #1a4d8f;
  --kn-red: #8B1E1E;
  --kn-red-border: #5E1010;
  
  /* Feedback colors */
  /* jaune: #D4A574 rouge : 9A0000 */
  --color-green: #2C5530;
  --color-blue: #D4A574;
  --color-red: #8F0000;
  
  /* Base colors bg-cell-preview D4CFC1 */
  --bg-body: #F5F1E8;
  --bg-cell: #FFFEF9;
  --bg-cell-preview: #D4CFC1;
  --bg-white: #FFFEF9;
  
  --text-primary: #222;
  --text-secondary: #444;
  --text-tertiary: #777;
  --text-dark: #111;
  --text-on-dark: #fff;
  --text-medium: #555;
  
  --border-dark: #444;
  --border-medium: #ccc;
  --border-strong: #333;
  
  /* Fonts */
  --font-heading: 'Playfair Display', serif;
  --font-body: 'Inter', sans-serif;
  
  /* Sizes - Desktop */
  --size-cell: 60px;
  --size-mini-cell: 20px;
  --size-piece: 40px;
  --size-piece-rook: 35px;
  --size-piece-btn: 28px;
  --size-piece-btn-rook: 24px;
  --size-mini-piece: 14px;
  --size-mini-piece-rook: 12px;
  
  /* Spacing */
  --gap-board: 5px;
  --gap-mini-board: 2px;
  --gap-controls: 10px;
  
  /* Borders */
  --border-radius-small: 4px;
  --border-radius-medium: 6px;
  --border-radius-large: 8px;
  --border-radius-modal: 12px;
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-medium: 0.2s;
  --transition-slow: 0.5s ease-in-out;
  
  /* Shadows and effects */
  --modal-overlay: rgba(0, 0, 0, 0.6);
  --toast-bg: rgba(50, 50, 50, 0.9);
}

/* ============================================
   BASE STYLES
   ============================================ */
* {
  box-sizing: border-box;
}

body {
  font-family: var(--font-body);
  font-weight: 300;
  text-align: center;
  background: var(--bg-body);
  color: var(--text-primary);
  margin: 0;
  padding: 0;
}

h1 {
  font-family: var(--font-heading);
  font-size: 30px;
  margin: 20px;
  color: var(--text-dark);
  text-shadow: none;
  letter-spacing: 2px;
}

h1,
.piece-rule h3 {
  font-family: var(--font-heading);
  text-transform: uppercase;
}

p,
.piece-rule p {
  font-family: var(--font-body);
  text-transform: none;
  font-size: 14px;
}

/* ============================================
   LAYOUT
   ============================================ */
#header {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  margin: 20px 0;
  padding: 0 20px;
  padding-right: max(20px, env(safe-area-inset-right));
}

#header h1 img {
  height: 80px;
  width: auto;
  display: block;
}

#header-buttons {
  position: absolute;
  right: 20px;
  right: max(20px, env(safe-area-inset-right));
  display: flex;
  gap: var(--gap-controls);
}

#mission {
  font-size: 18px;
  font-weight: 500;
  margin: 10px auto 15px auto;
  color: var(--text-secondary);
  padding: 0 20px;
}

/* ============================================
   BOARD - Main game board
   ============================================ */
#board {
  display: grid;
  grid-template-columns: repeat(5, var(--size-cell));
  grid-template-rows: repeat(5, var(--size-cell));
  gap: var(--gap-board);
  justify-content: center;
  margin: 20px auto;
}

#board.locked .cell {
  pointer-events: none;
}

.cell {
  width: var(--size-cell);
  height: var(--size-cell);
  border: 1px solid var(--border-dark);
  border-radius: 2px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--size-piece);
  cursor: pointer;
  user-select: none;
  background-color: var(--bg-cell);
  transition: background-color var(--transition-fast);
}

/* ============================================
   MINI-BOARD - Attempt history
   ============================================ */
#history {
  display: flex;
  gap: 20px;
  justify-content: center;
  margin-bottom: 20px;
  flex-wrap: wrap;
  padding: 0 10px;
}

.mini-board {
  display: grid;
  grid-template-columns: repeat(5, var(--size-mini-cell));
  grid-template-rows: repeat(5, var(--size-mini-cell));
  gap: var(--gap-mini-board);
  justify-content: center;
  margin-bottom: 10px;
}

.mini-cell {
  width: var(--size-mini-cell);
  height: var(--size-mini-cell);
  background: var(--bg-cell);
  border-radius: 2px;
  border: 1px solid var(--border-medium);
  text-align: center;
  font-size: var(--size-mini-piece);
  line-height: var(--size-mini-cell);
  display: flex;
  align-items: center;
  justify-content: center;
}

.mini-cell.green,
.mini-cell.orange,
.mini-cell.red,
.mini-cell.blocked {
  border: 1px solid currentColor;
}

/* ============================================
   BUTTONS
   ============================================ */
#validateBtn,
#resetBtn,
.debug-btn {
  margin: 15px 5px;
  font-size: 18px;
  padding: 10px 20px;
  background: var(--text-primary);
  color: var(--bg-white);
  border: 1px solid var(--border-dark);
  border-radius: var(--border-radius-small);
  cursor: pointer;
  transition: var(--transition-medium);
}

#validateBtn:hover,
#resetBtn:hover {
  background: var(--kn-gold);
  border: 1px solid var(--kn-gold-border);
}

#validateBtn:disabled,
#resetBtn:disabled,
.piece-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.debug-btn {
  margin-top: 20px;
  background: #555;
  color: #fff;
  font-size: 16px;
  padding: 8px 16px;
  border: 1px solid #333;
}

.debug-btn:hover {
  background: #666;
}

/* Piece selection buttons */
.piece-btn {
  font-size: var(--size-piece-btn);
  margin: 5px;
  cursor: pointer;
  padding: 8px;
  border: 2px solid var(--border-dark);
  border-radius: var(--border-radius-medium);
  background: var(--bg-white);
  transition: var(--transition-medium);
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  -webkit-tap-highlight-color: transparent;
}

.rook-symbol {
  font-size: var(--size-piece-btn-rook);
  margin: 1px;
  padding: 1px;
}

@media (hover: hover) and (pointer: fine) {
  .piece-btn:hover:not(.active):not(:disabled) {
    background: var(--kn-gold);
    border-color: var(--kn-gold-border);
    color: var(--bg-white);
  }
}

.piece-btn.active {
  background: var(--kn-gold);
  border-color: var(--kn-gold-border);
  color: var(--bg-white);
}

/* Icon buttons */
.icon-btn {
  background: none;
  border: none;
  padding: 0;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-fast);
}

.icon-btn svg {
  width: 24px;
  height: 24px;
  padding: 0;
}

.icon-btn:hover {
  transform: scale(1.2);
  color: var(--kn-gold);
}

/* Share button */
#shareBtn {
  margin: 15px;
  font-size: 18px;
  padding: 10px 15px;
  background: var(--kn-gold);
  border: 1px solid var(--kn-gold-border);
  border-radius: var(--border-radius-medium);
  color: var(--bg-white);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: var(--transition-medium);
}

#shareBtn:hover {
  background: var(--kn-gold-border);
}

/* ============================================
   FEEDBACK & COLORS
   ============================================ */
.green {
  background-color: var(--color-green);
  color: var(--bg-white);
}

.orange {
  background-color: var(--color-blue);
  color: var(--bg-white);
}

.red {
  background-color: var(--color-red);
  color: var(--bg-white);
}

.red-text {
  color: var(--color-red);
}

.blue-text {
  color: var(--color-blue);
}

.green-text {
  color: var(--color-green);
}

/* ============================================
   MODALS
   ============================================ */
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: var(--modal-overlay);
  overflow-y: auto;
}

.modal.active {
  display: block;
}

.modal-content {
  background: var(--bg-white);
  margin: 50px auto;
  padding: 20px;
  border: 2px solid var(--border-strong);
  border-radius: var(--border-radius-large);
  max-width: 90%;
  position: relative;
}

#rulesModal .modal-content {
  width: 80%;
  max-width: 700px;
}

#statsModal .modal-content {
  width: 65%;
  max-width: 500px;
}

#victoryModal .modal-content {
  margin: 10% auto;
  border-radius: var(--border-radius-modal);
  width: 320px;
  max-width: 90%;
  text-align: center;
}

.close {
  position: absolute;
  font-size: 28px;
  cursor: pointer;
  line-height: 1;
  top: 15px;
  right: 20px;
}

.close:hover {
  color: var(--kn-gold);
}

/* ============================================
   RULES LAYOUT
   ============================================ */
.rule-block {
  display: flex;
  align-items: center;
  margin: 15px 0;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;
}

.rule-block img {
  max-width: 150px;
}

.rule-block p {
  text-align: center;
  max-width: 400px;
  margin: 0;
}

.pieces-row {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

.piece-rule {
  text-align: center;
  flex: 1;
  min-width: 100px;
}

.piece-rule img {
  max-width: 100px;
}

.colors-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin: 20px 0;
  flex-wrap: wrap;
  gap: 15px;
}

.color-example {
  text-align: center;
  flex: 1;
  min-width: 100px;
}

.color-example img {
  max-width: 100px;
  display: block;
  margin: 0 auto 8px auto;
}

.color-example p {
  margin: 0;
  font-size: 14px;
}

/* ============================================
   STATS
   ============================================ */
#statsTitle {
  text-align: center;
  margin-bottom: 5px;
  font-size: 20px;
  font-weight: 600;
}

#statsSubtitle {
  text-align: center;
  font-size: 16px;
  font-weight: normal;
  color: var(--text-secondary);
  margin-bottom: 10px;
}

#statsGraph {
  margin-top: 30px;
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
}

#statsMessage {
  text-align: center;
  font-size: 14px;
  color: var(--text-secondary);
  margin: 15px 0;
  font-style: italic;
}

.stat-row {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 6px 0;
  width: 100%;
  max-width: 500px;
}

.stat-label {
  width: 60px;
  font-weight: bold;
  text-align: right;
  margin-right: 10px;
  flex-shrink: 0;
}

.stat-bar {
  flex: 1;
  background: var(--bg-white);
  border-radius: 4px;
  position: relative;
  height: 24px;
}

.stat-bar-fill {
  height: 100%;
  border-radius: 4px;
  text-align: right;
  line-height: 24px;
  font-size: 14px;
  font-weight: bold;
  padding-right: 5px;
  color: #000;
  width: 0;
  transition: width 1.5s ease;
  will-change: width;
}

#statsToggle {
  display: flex;
  justify-content: center;
  margin: 20px auto;
  background: var(--bg-white);
  border: 2px solid var(--kn-gold-border);
  border-radius: 25px;
  overflow: hidden;
  width: 240px;
  max-width: 90%;
}

.toggle-option {
  flex: 1;
  text-align: center;
  padding: 10px 0;
  cursor: pointer;
  font-weight: bold;
  color: var(--text-primary);
  transition: all 0.3s ease;
}

.toggle-option.active {
  background: var(--kn-gold);
  color: var(--bg-white);
}

/* ============================================
   VICTORY MODAL STATS
   ============================================ */
.bar {
  height: 20px;
  margin: 6px 0;
  display: flex;
  border: 1px solid var(--border-dark);
  border-radius: var(--border-radius-small);
  overflow: hidden;
}

.bar-segment {
  height: 100%;
  transition: width 0.5s ease;
}

.bar-green {
  background: var(--color-green);
}

.bar-blue {
  background: var(--color-blue);
}

.bar-red {
  background: var(--color-red);
}

/* ============================================
   TOAST NOTIFICATION
   ============================================ */
#toast {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background-color: var(--toast-bg);
  color: var(--bg-white);
  padding: 10px 20px;
  border-radius: var(--border-radius-large);
  font-size: 16px;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-slow);
  z-index: 2000;
  max-width: 90%;
}

#toast.show {
  opacity: 1;
}

/* ============================================
   COUNTDOWN SCREEN
   ============================================ */
#countdownScreen {
  display: none;
  text-align: center;
  margin-top: 50px;
  padding: 0 20px;
}

#countdown {
  font-size: 2em;
  font-weight: bold;
  margin: 20px 0;
}

#viewResultsBtn {
  margin: 20px auto;
  font-size: 18px;
  padding: 10px 20px;
  background: var(--text-primary);
  color: var(--bg-white);
  border: 2px solid var(--border-dark);
  border-radius: var(--border-radius-small);
  cursor: pointer;
  transition: var(--transition-medium);
  display: block;
}

#viewResultsBtn:hover {
  background: var(--kn-gold);
  border: 2px solid var(--kn-gold-border);
}

/* ============================================
   FOOTER
   ============================================ */
footer {
  text-align: center;
  margin-top: 40px;
  padding: 20px;
  font-size: 12px;
  color: var(--text-tertiary);
}

footer a {
  color: var(--text-medium);
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

/* ============================================
   CHESS PIECES
   ============================================ */
.chess-piece {
  font-size: var(--size-piece);
  line-height: 1;
}

.chess-piece.rook {
  font-size: var(--size-piece-rook);
  position: relative;
  top: 2px;
}

.mini-piece {
  font-size: var(--size-mini-piece);
  line-height: 1;
}

.mini-piece.rook {
  font-size: var(--size-mini-piece-rook);
  position: relative;
  top: 1px;
}

/* ============================================
   ANIMATIONS
   ============================================ */
.fade-cell {
  animation: fadeBg 4s ease forwards;
}

@keyframes fadeBg {
  from {
    background-color: var(--bg-cell);
  }
  to {
    background-color: var(--color-green);
  }
}

.fade-piece {
  opacity: 0;
  transition: opacity 4s ease;
  font-size: var(--size-piece);
}

.fade-in {
  opacity: 0;
  animation: fadeIn 0.8s forwards;
}

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

.shake {
  animation: shake 0.4s ease;
}

@keyframes shake {
  0% {
    transform: translateX(0);
  }
  20% {
    transform: translateX(-8px);
  }
  40% {
    transform: translateX(8px);
  }
  60% {
    transform: translateX(-6px);
  }
  80% {
    transform: translateX(6px);
  }
  100% {
    transform: translateX(0);
  }
}

/* ============================================
   RESPONSIVE - TABLET
   ============================================ */
@media (max-width: 768px) {
  :root {
    --size-cell: 50px;
    --size-mini-cell: 16px;
    --size-piece: 34px;
    --size-piece-rook: 30px;
  }

  h1 {
    font-size: 42px;
    margin: 15px;
  }

  #header h1 img {
    height: 60px;
  }

  #header-buttons {
    right: 10px;
  }

  #mission {
    font-size: 16px;
  }

  #history {
    gap: 15px;
  }

  .modal-content {
    margin: 30px auto;
    padding: 15px;
  }

  #rulesModal .modal-content,
  #statsModal .modal-content {
    width: 90%;
  }

  .rule-block {
    flex-direction: column;
    text-align: center;
  }

  .rule-block img {
    margin-right: 0;
  }
}

/* ============================================
   RESPONSIVE - MOBILE
   ============================================ */
@media (max-width: 480px) {
  :root {
    --size-cell: 45px;
    --size-mini-cell: 14px;
    --size-piece: 30px;
    --size-piece-rook: 26px;
    --size-piece-btn: 24px;
    --size-piece-btn-rook: 20px;
    --size-mini-piece: 11px;
    --size-mini-piece-rook: 9px;
    --gap-board: 3px;
  }

  h1 {
    font-size: 32px;
    margin: 10px;
  }

  #header {
    margin: 10px 0;
    padding: 0 10px;
    padding-right: max(15px, calc(env(safe-area-inset-right) + 5px));
  }

  #header h1 img {
    height: 50px;
  }

  #header-buttons {
    right: 10px;
    right: max(15px, calc(env(safe-area-inset-right) + 5px));
    gap: 5px;
  }

  .icon-btn svg {
    width: 23px;
    height: 23px;
  }

  #mission {
    font-size: 14px;
    margin: 10px auto;
  }

  #history {
    gap: 10px;
  }

  .piece-btn {
    margin: 3px;
    padding: 6px;
  }

  #validateBtn,
  #resetBtn,
  .debug-btn {
    font-size: 16px;
    padding: 8px 15px;
    margin: 10px 3px;
  }

  .modal-content {
    margin: 20px auto;
    padding: 15px;
  }

  #victoryModal .modal-content {
    width: 280px;
  }

  #shareBtn {
    font-size: 16px;
    padding: 8px 12px;
  }

  .colors-row {
    flex-direction: column;
  }

  .color-example {
    margin-bottom: 15px;
  }

  .pieces-row {
    flex-direction: column;
  }

  .piece-rule {
    margin-bottom: 15px;
  }

  #statsGraph {
    margin-top: 20px;
  }

  .stat-label {
    width: 40px;
    font-size: 12px;
    margin-right: 5px;
  }

  .stat-bar {
    height: 20px;
  }

  .stat-bar-fill {
    font-size: 12px;
    line-height: 20px;
  }

  #countdown {
    font-size: 1.5em;
  }
}

/* ============================================
   RESPONSIVE - SMALL MOBILE
   ============================================ */
@media (max-width: 360px) {
  :root {
    --size-cell: 38px;
    --size-mini-cell: 12px;
    --size-piece: 26px;
    --size-piece-rook: 23px;
  }

  h1 {
    font-size: 28px;
  }

  #header h1 img {
    height: 40px;
  }

  #mission {
    font-size: 13px;
  }

  #history {
    gap: 8px;
  }
}

/* ============================================
   PRINT STYLES
   ============================================ */
@media print {
  .modal,
  #header-buttons,
  #validateBtn,
  #resetBtn,
  .debug-btn,
  #pieceSelector,
  #toast {
    display: none !important;
  }
}

/* ============================================
   BLOCKED CELLS
   ============================================ */
.cell.blocked {
  background-color: #111;
  border: 1px solid #333;
  cursor: not-allowed;
}
.mini-cell.blocked {
  background-color: #111 !important;
  border: 1px solid #FFFEF9;
}
.cell.fade-cell.blocked {
  background-color: #111 !important;
}

/* ============================================
   SAFARI/iOS
   ============================================ */

button, .icon-btn, .piece-btn {
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  -webkit-tap-highlight-color: transparent;
}

.icon-btn {
  color: var(--text-primary);
}

.icon-btn svg {
  stroke: currentColor;
}

.piece-btn {
  color: var(--text-primary);
}

.piece-btn:not(.active) {
  color: var(--text-primary);
  background: var(--bg-white);
}

#validateBtn, #resetBtn {
  -webkit-tap-highlight-color: transparent;
  outline: none;
  touch-action: manipulation;
}

@media (hover: none) and (pointer: coarse) {
  .cell {
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
  }
  
  .piece-btn:active:not(:disabled) {
    transform: scale(0.95);
  }
  
  #validateBtn:active,
  #resetBtn:active {
    background: var(--text-primary) !important;
    border-color: var(--border-dark) !important;
    transform: scale(0.98);
  }
}

@media (hover: none) and (pointer: coarse) {
  #validateBtn,
  #resetBtn {
    background: var(--text-primary) !important;
    border: 1px solid var(--border-dark) !important;
  }
  
  #validateBtn:active,
  #resetBtn:active,
  #validateBtn:focus,
  #resetBtn:focus {
    background: var(--text-primary) !important;
    border: 1px solid var(--border-dark) !important;
  }
}

/* ============================================
   LARGE SCREENS
   ============================================ */
@media (min-width: 1400px) {
  body {
    max-width: 1400px;
    margin: 0 auto;
  }
}

/* ============================================
   ANDROID ONLY - Equal rook button size
   ============================================ */
.is-android {
  --size-piece-btn-rook: 24px !important;
  --size-piece-rook: 30px !important;
  --size-mini-piece-rook: 11px !important;
}

.is-android .rook-symbol {
  font-size: 24px !important;
  margin: 0 !important;
  padding: 0 !important;
}

/* ============================================
   RULES MODAL - Don't show again checkbox
   ============================================ */
.rules-checkbox-container {
  margin-top: 20px;
  text-align: center;
  padding: 10px;
  border-top: 1px solid var(--border-medium);
}

.rules-checkbox-container label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 14px;
  color: var(--text-secondary);
}

.rules-checkbox-container input[type="checkbox"] {
  cursor: pointer;
  width: 16px;
  height: 16px;
}

/* ============================================
   LANGUAGE DROPDOWN
   ============================================ */
#langDropdown {
  position: absolute;
  top: 50px;
  right: 20px;
  right: max(20px, env(safe-area-inset-right));
  background: var(--bg-white);
  border: 2px solid var(--border-dark);
  border-radius: var(--border-radius-medium);
  display: none;
  flex-direction: column;
  min-width: 150px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  z-index: 100;
}

#langDropdown.active {
  display: flex;
}

.lang-option {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  text-decoration: none;
  color: var(--text-primary);
  font-size: 16px;
  transition: var(--transition-fast);
  cursor: pointer;
}

.lang-option:hover {
  background: var(--bg-cell-preview);
}

.lang-option:first-child {
  border-radius: var(--border-radius-medium) var(--border-radius-medium) 0 0;
}

.lang-option:last-child {
  border-radius: 0 0 var(--border-radius-medium) var(--border-radius-medium);
}

.lang-flag {
  font-size: 20px;
}

@media (max-width: 480px) {
  #langDropdown {
    right: 10px;
    right: max(15px, calc(env(safe-area-inset-right) + 5px));
    min-width: 130px;
  }
  
  .lang-option {
    padding: 10px 12px;
    font-size: 14px;
  }
  
  .lang-flag {
    font-size: 18px;
  }
}

/* ============================================
   SETTINGS DROPDOWN
   ============================================ */
.settings-dropdown {
  position: absolute;
  top: 50px;
  right: 20px;
  background: var(--bg-white);
  border: 2px solid var(--border-dark);
  border-radius: var(--border-radius-medium);
  display: none;
  flex-direction: column;
  min-width: 180px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  z-index: 100;
  padding: 10px;
}

.settings-dropdown.active {
  display: flex;
}

.settings-section {
  margin-bottom: 10px;
  text-align: left;
}

.settings-section h4 {
  font-size: 14px;
  margin: 5px 0;
  color: var(--text-secondary);
}

.settings-options {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.settings-option {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  text-decoration: none;
  color: var(--text-primary);
  font-size: 14px;
  border-radius: 6px;
  transition: var(--transition-fast);
}

.settings-option:hover {
  background: var(--bg-cell-preview);
}

/* Toggle switch */
.switch {
  position: relative;
  display: inline-block;
  width: 40px;
  height: 22px;
  margin-right: 8px;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #ccc;
  transition: 0.4s;
  border-radius: 22px;
}

.slider:before {
  position: absolute;
  content: "";
  height: 16px;
  width: 16px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  transition: 0.4s;
  border-radius: 50%;
}

input:checked + .slider {
  background-color: var(--kn-gold);
}

input:checked + .slider:before {
  transform: translateX(18px);
}

#difficultyLabel {
  font-size: 14px;
  color: var(--text-secondary);
}