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

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
}

/* Home Page */
.home {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.home h1 {
  color: white;
  font-size: 3em;
  margin-bottom: 40px;
  text-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.home button {
  margin: 10px 0;
  padding: 15px 30px;
  font-size: 1.1em;
  font-weight: 600;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: transform 0.2s;
  background: white;
  color: #667eea;
}

.home button:hover {
  transform: translateY(-2px);
}

.home input {
  margin: 20px 0 10px;
  padding: 15px;
  font-size: 1.2em;
  border: 2px solid white;
  border-radius: 8px;
  text-align: center;
  text-transform: uppercase;
  width: 250px;
}

/* Game Page */
.game-container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px;
  gap: 20px;
}

.game-info {
  background: white;
  padding: 20px 40px;
  border-radius: 12px;
  text-align: center;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.game-info h2 {
  color: #333;
  margin-bottom: 10px;
}

.status {
  color: #667eea;
  font-weight: 600;
  font-size: 1.1em;
}

.player-color {
  color: #666;
  margin-top: 5px;
}

.game-board-wrapper {
  background: white;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
}

.timer {
  text-align: center;
  padding: 12px;
  font-size: 1.4em;
  font-weight: 700;
  color: #333;
  background: #f0f0f0;
  border-radius: 8px;
  margin: 10px 0;
}

/* Chess Board */
.chess-board {
  display: grid;
  grid-template-columns: repeat(8, 60px);
  grid-template-rows: repeat(8, 60px);
  border: 3px solid #333;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.chess-board.flipped {
  transform: rotate(180deg);
}

.chess-board.flipped .square {
  transform: rotate(180deg);
}

.square {
  width: 60px;
  height: 60px;
  display: flex;
  justify-content: center;
  align-items: center;
  cursor: pointer;
  transition: background-color 0.2s;
}

.square.light {
  background-color: #f0d9b5;
}

.square.dark {
  background-color: #b58863;
}

.square:hover {
  opacity: 0.8;
}

.square.selected {
  background-color: #7fa650 !important;
  box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.4);
}

.piece {
  font-size: 48px;
  user-select: none;
  pointer-events: none;
}

/* Game Controls */
.game-controls {
  width: 100%;
  max-width: 520px;
}

.btn {
  width: 100%;
  padding: 12px;
  border: none;
  border-radius: 8px;
  font-size: 1.1em;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s;
}

.btn:hover:not(:disabled) {
  transform: translateY(-2px);
}

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

.btn-danger {
  background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
  color: white;
}

/* Move History */
.move-history {
  background: white;
  padding: 20px;
  border-radius: 12px;
  width: 100%;
  max-width: 520px;
  max-height: 200px;
  overflow-y: auto;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.move-history h3 {
  color: #333;
  margin-bottom: 10px;
}

.moves-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.move-item {
  background: #667eea;
  color: white;
  padding: 6px 12px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.9em;
}

/* Responsive */
@media (max-width: 600px) {
  .chess-board {
    grid-template-columns: repeat(8, 45px);
    grid-template-rows: repeat(8, 45px);
  }

  .square {
    width: 45px;
    height: 45px;
  }

  .piece {
    font-size: 36px;
  }
}

/* Promotion Dialog */
.board-container {
  position: relative;
}

.promotion-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
}

.promotion-dialog {
  background: white;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

.promotion-dialog h3 {
  margin: 0 0 20px 0;
  text-align: center;
  color: #333;
}

.promotion-pieces {
  display: flex;
  gap: 15px;
}

.promotion-button {
  width: 80px;
  height: 80px;
  border: 3px solid #667eea;
  background: white;
  border-radius: 8px;
  font-size: 48px;
  cursor: pointer;
  transition: all 0.2s;
}

.promotion-button:hover {
  background: #667eea;
  transform: scale(1.1);
}