/* 全局样式和CSS变量 */
:root {
  /* 淡蓝主题 */
  --primary-color: #E3F2FD;
  --secondary-color: #64B5F6;
  --accent-color: #2196F3;
  --background-color: #FAFAFA;
  --text-color: #333333;
  --border-color: #CCCCCC;
  --success-color: #4CAF50;
  --error-color: #FF5252;
  --warning-color: #FF9800;
  --shadow-light: 0 2px 8px rgba(0,0,0,0.1);
  --shadow-medium: 0 4px 16px rgba(0,0,0,0.15);
  --border-radius: 8px;
  --transition: all 0.3s ease;
}

/* 浅绿主题 */
[data-theme="green"] {
  --primary-color: #E8F5E8;
  --secondary-color: #81C784;
  --accent-color: #4CAF50;
}

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

body {
  font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--background-color) 100%);
  color: var(--text-color);
  min-height: 100vh;
  line-height: 1.6;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 20px;
}

/* 头部样式 */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 30px;
  padding: 20px 0;
}

.logo {
  font-size: 2.5rem;
  font-weight: 600;
  color: var(--accent-color);
  text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
}

.theme-toggle {
  position: relative;
}

.theme-btn {
  background: var(--secondary-color);
  border: none;
  border-radius: 50%;
  width: 50px;
  height: 50px;
  font-size: 1.5rem;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow-light);
}

.theme-btn:hover {
  transform: scale(1.1);
  box-shadow: var(--shadow-medium);
}

/* 主游戏区域 */
.game-container {
  display: grid;
  grid-template-columns: 280px 1fr 280px;
  gap: 30px;
  align-items: start;
}

/* 控制面板 */
.control-panel {
  background: white;
  border-radius: var(--border-radius);
  padding: 25px;
  box-shadow: var(--shadow-light);
  position: sticky;
  top: 20px;
}

.difficulty-section h3 {
  margin-bottom: 15px;
  color: var(--accent-color);
  font-weight: 500;
}

.difficulty-buttons {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 25px;
}

.difficulty-btn {
  background: var(--primary-color);
  border: 2px solid transparent;
  border-radius: var(--border-radius);
  padding: 12px 16px;
  cursor: pointer;
  transition: var(--transition);
  text-align: left;
}

.difficulty-btn:hover {
  border-color: var(--secondary-color);
  transform: translateY(-2px);
}

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

.difficulty-name {
  display: block;
  font-weight: 500;
  font-size: 1.1rem;
}

.difficulty-desc {
  display: block;
  font-size: 0.9rem;
  opacity: 0.8;
}

/* 游戏控制 */
.game-controls {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.timer-section {
  text-align: center;
  padding: 15px;
  background: var(--primary-color);
  border-radius: var(--border-radius);
}

.timer {
  font-size: 2rem;
  font-weight: 600;
  color: var(--accent-color);
  margin: 10px 0;
}

.best-time {
  font-size: 0.9rem;
  opacity: 0.7;
}

/* 提示开关 */
.hints-section {
  display: flex;
  align-items: center;
  gap: 10px;
}

.switch {
  position: relative;
  display: inline-block;
  width: 50px;
  height: 24px;
}

.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: var(--transition);
  border-radius: 24px;
}

.slider:before {
  position: absolute;
  content: "";
  height: 18px;
  width: 18px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  transition: var(--transition);
  border-radius: 50%;
}

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

input:checked + .slider:before {
  transform: translateX(26px);
}

/* 操作按钮 */
.action-buttons {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.action-btn {
  background: white;
  border: 2px solid var(--secondary-color);
  border-radius: var(--border-radius);
  padding: 10px 15px;
  cursor: pointer;
  transition: var(--transition);
  font-weight: 500;
}

.action-btn:hover {
  background: var(--secondary-color);
  color: white;
  transform: translateY(-1px);
}

/* 数独网格容器 */
.sudoku-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

/* 数独网格 */
.sudoku-grid {
  display: grid;
  grid-template-columns: repeat(9, 1fr);
  gap: 2px;
  background: var(--border-color);
  border: 3px solid var(--accent-color);
  border-radius: var(--border-radius);
  padding: 8px;
  box-shadow: var(--shadow-medium);
  position: relative;
}

.sudoku-cell {
  width: 50px;
  height: 50px;
  background: white;
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
}

.sudoku-cell:hover {
  background: var(--primary-color);
}

.sudoku-cell.selected {
  background: var(--secondary-color);
  color: white;
  box-shadow: inset 0 0 0 2px var(--accent-color);
}

.sudoku-cell.highlighted {
  background: rgba(100, 181, 246, 0.3);
}

.sudoku-cell.same-number {
  background: rgba(76, 175, 80, 0.3);
}

.sudoku-cell.error {
  background: var(--error-color);
  color: white;
  animation: shake 0.5s ease-in-out;
}

.sudoku-cell.given {
  background: var(--primary-color);
  font-weight: 600;
  color: var(--accent-color);
}

.sudoku-cell.completed {
  animation: pulse 0.6s ease-in-out;
}

/* 3x3宫格边框 */
.sudoku-cell:nth-child(3n) {
  border-right: 2px solid var(--accent-color);
}

.sudoku-cell:nth-child(n+19):nth-child(-n+27),
.sudoku-cell:nth-child(n+46):nth-child(-n+54) {
  border-bottom: 2px solid var(--accent-color);
}

/* 候选数字 */
.candidates {
  position: absolute;
  top: 2px;
  left: 2px;
  right: 2px;
  bottom: 2px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(3, 1fr);
  font-size: 0.6rem;
  color: var(--accent-color);
}

.candidate {
  display: flex;
  align-items: center;
  justify-content: center;
}

/* 数字面板 */
.number-panel {
  background: white;
  border-radius: var(--border-radius);
  padding: 25px;
  box-shadow: var(--shadow-light);
  position: sticky;
  top: 20px;
}

.number-panel h4 {
  margin-bottom: 15px;
  color: var(--accent-color);
  font-weight: 500;
}

.number-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-bottom: 25px;
}

.number-btn {
  width: 50px;
  height: 50px;
  background: var(--primary-color);
  border: 2px solid transparent;
  border-radius: var(--border-radius);
  font-size: 1.2rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.number-btn:hover {
  background: var(--secondary-color);
  color: white;
  transform: scale(1.05);
}

.number-btn.selected {
  background: var(--accent-color);
  color: white;
  border-color: var(--accent-color);
}

.erase-btn {
  background: var(--error-color);
  color: white;
}

.erase-btn:hover {
  background: #d32f2f;
}

/* 提示面板 */
.hint-panel {
  background: var(--primary-color);
  border-radius: var(--border-radius);
  padding: 15px;
  margin-bottom: 20px;
}

.hint-content {
  background: white;
  border-radius: var(--border-radius);
  padding: 12px;
  margin: 10px 0;
  min-height: 60px;
  font-size: 0.9rem;
  line-height: 1.4;
}

.hint-btn {
  width: 100%;
  background: var(--secondary-color);
  color: white;
  border: none;
  border-radius: var(--border-radius);
  padding: 10px;
  cursor: pointer;
  transition: var(--transition);
  font-weight: 500;
}

.hint-btn:hover {
  background: var(--accent-color);
}

/* 打印区域 */
.print-section {
  border-top: 1px solid var(--border-color);
  padding-top: 15px;
}

.print-btn {
  width: 100%;
  background: white;
  border: 2px solid var(--secondary-color);
  border-radius: var(--border-radius);
  padding: 10px;
  margin-bottom: 8px;
  cursor: pointer;
  transition: var(--transition);
  font-size: 0.9rem;
}

.print-btn:hover {
  background: var(--secondary-color);
  color: white;
}

/* 移动端数字面板 */
.mobile-number-panel {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: white;
  border-top: 2px solid var(--border-color);
  padding: 15px;
  box-shadow: 0 -4px 16px rgba(0,0,0,0.1);
  z-index: 1000;
}

.mobile-numbers {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 8px;
  margin-bottom: 10px;
}

.mobile-number-btn {
  height: 45px;
  background: var(--primary-color);
  border: 2px solid transparent;
  border-radius: var(--border-radius);
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.mobile-number-btn:active {
  transform: scale(0.95);
  background: var(--secondary-color);
  color: white;
}

.mobile-controls {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.mobile-control-btn {
  height: 40px;
  background: var(--secondary-color);
  color: white;
  border: none;
  border-radius: var(--border-radius);
  font-size: 1rem;
  cursor: pointer;
  transition: var(--transition);
}

.mobile-control-btn:active {
  transform: scale(0.95);
  background: var(--accent-color);
}

/* 游戏状态 */
.game-status {
  padding: 15px 25px;
  border-radius: var(--border-radius);
  font-weight: 500;
  text-align: center;
  transition: var(--transition);
}

.game-status.success {
  background: var(--success-color);
  color: white;
}

.game-status.error {
  background: var(--error-color);
  color: white;
}

.game-status.info {
  background: var(--primary-color);
  color: var(--accent-color);
}

/* 模态框 */
.modal {
  display: none;
  position: fixed;
  z-index: 2000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0,0,0,0.5);
  backdrop-filter: blur(5px);
}

.modal-content {
  background: white;
  margin: 10% auto;
  padding: 30px;
  border-radius: var(--border-radius);
  width: 90%;
  max-width: 400px;
  text-align: center;
  box-shadow: var(--shadow-medium);
  animation: modalSlideIn 0.3s ease-out;
}

.completion-animation {
  font-size: 4rem;
  margin-bottom: 20px;
  animation: bounce 1s infinite;
}

.completion-stats {
  margin: 20px 0;
  padding: 15px;
  background: var(--primary-color);
  border-radius: var(--border-radius);
}

.new-record {
  color: var(--success-color);
  font-weight: 600;
}

.modal-buttons {
  display: flex;
  gap: 10px;
  margin-top: 20px;
}

.modal-btn {
  flex: 1;
  padding: 12px 20px;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-weight: 500;
  transition: var(--transition);
}

.modal-btn.primary {
  background: var(--accent-color);
  color: white;
}

.modal-btn.secondary {
  background: var(--border-color);
  color: var(--text-color);
}

.modal-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-light);
}

/* 暂停遮罩 */
.pause-overlay {
  display: none;
  position: fixed;
  z-index: 1500;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0,0,0,0.8);
  backdrop-filter: blur(10px);
}

.pause-content {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  color: white;
}

.pause-content h2 {
  font-size: 2.5rem;
  margin-bottom: 30px;
}

.resume-btn {
  background: var(--accent-color);
  color: white;
  border: none;
  border-radius: var(--border-radius);
  padding: 15px 30px;
  font-size: 1.1rem;
  cursor: pointer;
  transition: var(--transition);
}

.resume-btn:hover {
  background: var(--secondary-color);
  transform: scale(1.05);
}

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

@keyframes pulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); }
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
  40% { transform: translateY(-10px); }
  60% { transform: translateY(-5px); }
}

@keyframes modalSlideIn {
  from {
    opacity: 0;
    transform: translateY(-50px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes numberPop {
  0% { transform: scale(0.8); opacity: 0; }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); opacity: 1; }
}

.number-pop {
  animation: numberPop 0.2s ease-out;
}

/* 响应式设计 */
@media (max-width: 1200px) {
  .game-container {
    grid-template-columns: 250px 1fr 250px;
    gap: 20px;
  }
  
  .sudoku-cell {
    width: 45px;
    height: 45px;
    font-size: 1.2rem;
  }
}

@media (max-width: 992px) {
  .game-container {
    grid-template-columns: 1fr;
    gap: 20px;
  }
  
  .control-panel,
  .number-panel {
    position: static;
    order: 2;
  }
  
  .sudoku-container {
    order: 1;
  }
  
  .mobile-number-panel {
    display: block;
  }
  
  .number-panel {
    display: none;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 10px;
  }
  
  .header {
    margin-bottom: 20px;
  }
  
  .logo {
    font-size: 2rem;
  }
  
  .sudoku-cell {
    width: 35px;
    height: 35px;
    font-size: 1rem;
  }
  
  .control-panel {
    padding: 15px;
  }
  
  .difficulty-buttons {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
  }
  
  .action-buttons {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
  }
}

@media (max-width: 480px) {
  .sudoku-cell {
    width: 30px;
    height: 30px;
    font-size: 0.9rem;
  }
  
  .mobile-numbers {
    grid-template-columns: repeat(5, 1fr);
  }
  
  .mobile-number-btn {
    height: 40px;
    font-size: 1rem;
  }
}

/* 打印样式 */
@media print {
  body * {
    visibility: hidden;
  }
  
  .print-container,
  .print-container * {
    visibility: visible;
  }
  
  .print-container {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
  }
  
  .print-sudoku {
    page-break-inside: avoid;
    margin-bottom: 30px;
  }
  
  .print-grid {
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    gap: 1px;
    border: 2px solid #000;
    width: 300px;
    height: 300px;
    margin: 20px auto;
  }
  
  .print-cell {
    border: 1px solid #666;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: bold;
  }
  
  .print-cell:nth-child(3n) {
    border-right: 2px solid #000;
  }
  
  .print-cell:nth-child(n+19):nth-child(-n+27),
  .print-cell:nth-child(n+46):nth-child(-n+54) {
    border-bottom: 2px solid #000;
  }
  
  .print-header {
    text-align: center;
    margin-bottom: 15px;
  }
  
  .print-title {
    font-size: 18px;
    font-weight: bold;
    margin-bottom: 5px;
  }
  
  .print-info {
    font-size: 12px;
    color: #666;
  }
  
  .four-grid-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    page-break-inside: avoid;
  }
}