*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:linear-gradient(135deg,#667eea,#764ba2);min-height:100vh;display:flex;justify-content:center;align-items:center;padding:20px}#app{width:100%;max-width:600px}.screen{background:#fff;border-radius:20px;padding:30px;box-shadow:0 20px 60px #0000004d}.hidden{display:none!important}#lobby h1{text-align:center;color:#333;margin-bottom:30px;font-size:2em}.lobby-container{display:flex;flex-direction:column;gap:25px}.room-section{display:flex;flex-direction:column;gap:10px}.room-section h2{color:#555;font-size:1.2em}input{padding:12px 15px;border:2px solid #e0e0e0;border-radius:10px;font-size:16px;transition:border-color .3s}input:focus{outline:none;border-color:#667eea}button{padding:12px 20px;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:10px;font-size:16px;font-weight:600;cursor:pointer;transition:transform .2s,box-shadow .2s}button:hover{transform:translateY(-2px);box-shadow:0 5px 15px #667eea66}button:active{transform:translateY(0)}.status{text-align:center;padding:10px;border-radius:10px;font-weight:600}.status.connected{background:#d4edda;color:#155724}.status.disconnected{background:#f8d7da;color:#721c24}.lobby-message{margin-top:20px;padding:15px;background:#fff3cd;border:2px solid #ffc107;border-radius:10px;text-align:center;font-weight:600;min-height:50px;display:flex;align-items:center;justify-content:center;color:#856404}.game-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px;padding:15px;background:#f5f5f5;border-radius:10px}.player-info{display:flex;align-items:center;gap:10px;font-weight:600}.color-indicator{width:20px;height:20px;border-radius:50%;border:2px solid #333}.color-indicator.red{background:#c41e3a}.color-indicator.black{background:#1a1a1a}.game-status{display:flex;flex-direction:column;align-items:center;gap:10px}#turnIndicator{font-weight:600;color:#667eea}#leaveRoomBtn{padding:8px 15px;font-size:14px}.board-container{display:flex;justify-content:center;overflow-x:auto;padding:10px 0}#chessBoard{position:relative;width:400px;height:444px;background:wheat;border:3px solid #8b4513;border-radius:5px}.board-line{position:absolute;background:#8b4513}.board-line.horizontal{height:2px;width:360px;left:20px}.board-line.vertical{width:2px;height:400px;top:22px}.river{position:absolute;top:197px;left:20px;width:360px;height:50px;background:wheat;display:flex;justify-content:center;align-items:center;font-size:24px;color:#8b4513;font-weight:700}.chess-piece{position:absolute;width:40px;height:40px;border-radius:50%;display:flex;justify-content:center;align-items:center;font-size:20px;font-weight:700;cursor:pointer;transition:transform .2s,box-shadow .2s;-webkit-user-select:none;user-select:none;border:2px solid;z-index:10}.chess-piece.red{background:#fff;color:#c41e3a;border-color:#c41e3a}.chess-piece.black{background:#fff;color:#1a1a1a;border-color:#1a1a1a}.chess-piece:hover{transform:scale(1.1);box-shadow:0 5px 15px #0000004d}.chess-piece.selected{transform:scale(1.15);box-shadow:0 0 20px #667eeacc;border-color:#667eea}.valid-move{position:absolute;width:20px;height:20px;background:#667eea80;border-radius:50%;transform:translate(-50%,-50%);cursor:pointer;z-index:5}.valid-move:hover{background:#667eeacc;transform:translate(-50%,-50%) scale(1.2)}.game-message{margin-top:20px;padding:15px;background:#f0f0f0;border-radius:10px;text-align:center;font-weight:600;min-height:50px;display:flex;align-items:center;justify-content:center}@media (max-width: 500px){.screen{padding:20px}#lobby h1{font-size:1.5em}#chessBoard{width:320px;height:355px}.board-line.horizontal{width:288px;left:16px}.board-line.vertical{height:320px;top:17px}.river{top:158px;left:16px;width:288px;height:40px;font-size:18px}.chess-piece{width:32px;height:32px;font-size:16px}.valid-move{width:16px;height:16px}.game-header{flex-direction:column;gap:10px}}@media (max-width: 380px){#chessBoard{width:280px;height:311px}.board-line.horizontal{width:252px;left:14px}.board-line.vertical{height:280px;top:15px}.river{top:139px;left:14px;width:252px;font-size:16px}.chess-piece{width:28px;height:28px;font-size:14px}}