#number-matrix-game {
      font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
      max-width: 800px;
      margin: 20px auto;
      background: linear-gradient(135deg, #1a2a6c, #b21f1f, #1a2a6c);
      border-radius: 15px;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
      padding: 25px;
      color: white;
      position: relative;
      overflow: hidden;
    }
    
    #number-matrix-game::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      background: 
        radial-gradient(circle at 10% 20%, rgba(255,255,255,0.1) 0%, transparent 20%),
        radial-gradient(circle at 90% 80%, rgba(255,255,255,0.1) 0%, transparent 20%);
      pointer-events: none;
    }
    
    .game-header {
      text-align: center;
      margin-bottom: 20px;
      position: relative;
      z-index: 2;
    }
    
    .game-title {
      font-size: 28px;
      margin-bottom: 5px;
      text-shadow: 0 2px 4px rgba(0,0,0,0.5);
      background: linear-gradient(to right, #ffd700, #ffffff);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      letter-spacing: 1px;
    }
    
    .game-subtitle {
      font-size: 16px;
      opacity: 0.9;
      margin-bottom: 15px;
    }
    
    .game-stats {
      display: flex;
      justify-content: space-between;
      background: rgba(0, 0, 0, 0.3);
      border-radius: 10px;
      padding: 12px 20px;
      margin-bottom: 20px;
      box-shadow: 0 4px 8px rgba(0,0,0,0.2);
      position: relative;
      z-index: 2;
    }
    
    .stat-box {
      text-align: center;
      flex: 1;
    }
    
    .stat-label {
      font-size: 14px;
      opacity: 0.8;
      margin-bottom: 5px;
    }
    
    .stat-value {
      font-size: 24px;
      font-weight: bold;
      color: #ffd700;
    }
    
    .game-area {
      background: rgba(0, 0, 0, 0.25);
      border-radius: 12px;
      padding: 20px;
      margin-bottom: 20px;
      box-shadow: inset 0 0 15px rgba(0,0,0,0.4);
      position: relative;
      z-index: 2;
    }
    
    .target-container {
      text-align: center;
      margin-bottom: 25px;
    }
    
    .target-label {
      font-size: 18px;
      margin-bottom: 8px;
    }
    
    .target-number {
      font-size: 42px;
      font-weight: bold;
      color: #ff6b6b;
      background: rgba(0, 0, 0, 0.4);
      display: inline-block;
      padding: 10px 30px;
      border-radius: 50px;
      box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    }
    
    .number-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 15px;
      margin-bottom: 25px;
    }
    
    .number-card {
      background: linear-gradient(145deg, #3498db, #1a5276);
      border-radius: 10px;
      height: 80px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 32px;
      font-weight: bold;
      box-shadow: 0 6px 12px rgba(0,0,0,0.3);
      cursor: pointer;
      transition: all 0.2s ease;
      position: relative;
      overflow: hidden;
    }
    
    .number-card::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 4px;
      background: rgba(255,255,255,0.4);
    }
    
    .number-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 8px 15px rgba(0,0,0,0.4);
      background: linear-gradient(145deg, #3ca0e0, #1f618d);
    }
    
    .number-card.used {
      opacity: 0.5;
      transform: scale(0.95);
      background: linear-gradient(145deg, #7f8c8d, #34495e);
    }
    
    .expression-container {
      background: rgba(0, 0, 0, 0.4);
      border-radius: 10px;
      padding: 15px;
      margin-bottom: 20px;
      min-height: 60px;
      font-size: 26px;
      text-align: center;
      font-family: 'Courier New', monospace;
      letter-spacing: 2px;
      box-shadow: inset 0 0 10px rgba(0,0,0,0.5);
      border: 1px solid rgba(255,255,255,0.1);
    }
    
    .controls {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 12px;
      margin-bottom: 20px;
    }
    
    .control-btn {
      padding: 12px 0;
      border: none;
      border-radius: 8px;
      font-size: 20px;
      font-weight: bold;
      cursor: pointer;
      transition: all 0.2s;
      box-shadow: 0 4px 8px rgba(0,0,0,0.3);
      background: linear-gradient(to bottom, #f39c12, #e67e22);
      color: white;
    }
    
    .control-btn:hover {
      transform: translateY(-3px);
      box-shadow: 0 6px 12px rgba(0,0,0,0.4);
    }
    
    .control-btn:active {
      transform: translateY(1px);
    }
    
    .control-btn.operator {
      background: linear-gradient(to bottom, #9b59b6, #8e44ad);
    }
    
    .control-btn.special {
      background: linear-gradient(to bottom, #e74c3c, #c0392b);
    }
    
    .action-buttons {
      display: flex;
      gap: 15px;
      margin-top: 10px;
    }
    
    .action-btn {
      flex: 1;
      padding: 14px 0;
      border: none;
      border-radius: 8px;
      font-size: 18px;
      font-weight: bold;
      cursor: pointer;
      transition: all 0.3s;
      box-shadow: 0 4px 8px rgba(0,0,0,0.3);
    }
    
    #submit-btn {
      background: linear-gradient(to bottom, #2ecc71, #27ae60);
      color: white;
    }
    
    #reset-btn {
      background: linear-gradient(to bottom, #e67e22, #d35400);
      color: white;
    }
    
    #new-game-btn {
      background: linear-gradient(to bottom, #3498db, #2980b9);
      color: white;
    }
    
    .action-btn:hover {
      transform: translateY(-3px);
      box-shadow: 0 6px 12px rgba(0,0,0,0.4);
    }
    
    .action-btn:active {
      transform: translateY(1px);
    }
    
    .message-area {
      background: rgba(0, 0, 0, 0.4);
      border-radius: 10px;
      padding: 15px;
      margin-top: 20px;
      text-align: center;
      min-height: 30px;
      font-size: 18px;
      box-shadow: inset 0 0 10px rgba(0,0,0,0.5);
      border: 1px solid rgba(255,255,255,0.1);
    }
    
    .success {
      color: #2ecc71;
      font-weight: bold;
    }
    
    .error {
      color: #e74c3c;
    }
    
    .hint {
      color: #3498db;
    }
    
    .leaderboard {
      background: rgba(0, 0, 0, 0.3);
      border-radius: 10px;
      padding: 20px;
      margin-top: 20px;
      position: relative;
      z-index: 2;
    }
    
    .leaderboard h3 {
      text-align: center;
      margin-top: 0;
      margin-bottom: 15px;
      color: #ffd700;
    }
    
    .leaderboard-list {
      list-style-type: none;
      padding: 0;
      margin: 0;
    }
    
    .leaderboard-item {
      display: flex;
      justify-content: space-between;
      padding: 10px 15px;
      background: rgba(255, 255, 255, 0.1);
      margin-bottom: 8px;
      border-radius: 6px;
    }
    
    .leaderboard-item:nth-child(1) {
      background: linear-gradient(to right, rgba(255, 215, 0, 0.3), rgba(0, 0, 0, 0.2));
      font-weight: bold;
      color: #ffd700;
    }
    
    .leaderboard-item:nth-child(2) {
      background: linear-gradient(to right, rgba(192, 192, 192, 0.3), rgba(0, 0, 0, 0.2));
    }
    
    .leaderboard-item:nth-child(3) {
      background: linear-gradient(to right, rgba(205, 127, 50, 0.3), rgba(0, 0, 0, 0.2));
    }
    
    .timer-pulse {
      animation: pulse 1.5s infinite;
    }
    
    @keyframes pulse {
      0% { box-shadow: 0 0 0 0 rgba(46, 204, 113, 0.7); }
      70% { box-shadow: 0 0 0 10px rgba(46, 204, 113, 0); }
      100% { box-shadow: 0 0 0 0 rgba(46, 204, 113, 0); }
    }
    
    .number-pulse {
      animation: numberPulse 0.5s;
    }
    
    @keyframes numberPulse {
      0% { transform: scale(1); }
      50% { transform: scale(1.1); }
      100% { transform: scale(1); }
    }
    
    .confetti {
      position: absolute;
      width: 10px;
      height: 10px;
      background-color: #f00;
      border-radius: 50%;
      animation: confetti-fall 5s ease-in-out;
      z-index: 1;
    }
    
    @keyframes confetti-fall {
      0% { transform: translateY(-100px) rotate(0deg); opacity: 1; }
      100% { transform: translateY(1000px) rotate(720deg); opacity: 0; }
    }
    
    .solution-hint {
      text-align: center;
      margin-top: 15px;
      font-size: 14px;
      color: #3498db;
      cursor: pointer;
    }
    
    .solution-hint:hover {
      text-decoration: underline;
    }
    
    .difficulty-selector {
      display: flex;
      justify-content: center;
      gap: 10px;
      margin-bottom: 15px;
    }
    
    .difficulty-btn {
      padding: 8px 15px;
      border: none;
      border-radius: 20px;
      background: rgba(255,255,255,0.1);
      color: white;
      cursor: pointer;
      transition: all 0.3s;
    }
    
    .difficulty-btn.active {
      background: linear-gradient(to right, #3498db, #2ecc71);
      box-shadow: 0 0 10px rgba(46, 204, 113, 0.5);
    }
    
    .difficulty-btn:hover:not(.active) {
      background: rgba(255,255,255,0.2);
    }
    
    .challenge-info {
      text-align: center;
      margin-bottom: 10px;
      font-size: 14px;
      opacity: 0.8;
    }
    
    .success-message {
      font-size: 20px;
      padding: 15px;
      text-align: center;
      background: rgba(46, 204, 113, 0.2);
      border-radius: 10px;
      margin-top: 15px;
      animation: fadeIn 0.5s;
    }
    
    @keyframes fadeIn {
      from { opacity: 0; }
      to { opacity: 1; }
    }