♟️ 国际象棋Chess
在线国际象棋人机对战：完整规则（王车易位、吃过路兵、兵升变、将死与逼和、三次重复与 50 回合和棋），三档电脑难度，可执白、执黑或双人对战，支持悔棋与棋谱记录，电脑在后台思考不卡页面。Play chess online against the computer with full rules — castling, en passant, promotion, checkmate, stalemate, threefold repetition and the fifty-move rule — three levels, play white, black or two players, undo and a move list; the AI thinks in the background.
点击己方棋子，再点高亮的目标格走棋；兵到底线时可选择升变。键盘：方向键移动光标，回车 选择/走棋，U 悔棋，N 新游戏。Click one of your pieces, then a highlighted square. Pawns reaching the last rank let you choose a promotion. Keyboard: arrows move the cursor, Enter selects/moves, U undo, N new game.
玩法说明与常见问题How to play & FAQ
「国际象棋」怎么玩？How do I play Chess?
白方先走，双方轮流移动一枚棋子。王走一格；后走直线和斜线；车走直线；象走斜线；马走“日”字并可越子；兵向前走一格（首步可走两格）、斜前方吃子。将军时必须解除；对方的王无路可逃即“将死”获胜。White moves first and the sides alternate. The king moves one square; the queen moves along lines and diagonals; rooks along lines; bishops along diagonals; knights jump in an L; pawns move forward one square (two on their first move) and capture diagonally. You must get out of check; checkmate the enemy king to win.
支持哪些特殊规则？Which special rules are supported?
支持王车易位（短易位和长易位）、吃过路兵、兵升变（后、车、象、马任选），以及逼和、三次重复局面、50 回合无吃子无兵动、子力不足等和棋判定。Castling on both sides, en passant, promotion to queen, rook, bishop or knight, and draws by stalemate, threefold repetition, the fifty-move rule and insufficient material.
电脑有多强？How strong is the computer?
简单难度只看一两步并带随机性，适合入门；中等会做 4 层搜索；困难在后台用 2 秒左右做更深的搜索（含置换表、吃子延伸），能发现大多数战术组合。Easy looks a move or two ahead with some randomness; Normal searches about four plies; Hard spends about two seconds in the background on a deeper search with a transposition table and capture extensions, catching most tactics.
可以两个人一起下吗？Can two people play?
可以，在「执子」里选「双人对战」，两人在同一台设备上轮流走棋，棋盘不会翻转。Yes — choose “Two players” under Play as and take turns on the same device.
「国际象棋」免费吗？需要下载吗？Is Chess free? Do I need to download anything?
完全免费，无需注册、下载或安装，打开网页就能玩，手机、平板和电脑都支持；游戏完全在你的浏览器本地运行，不会上传任何数据。It is completely free with no sign-up, download or install — just open the page on a phone, tablet or computer. The game runs entirely in your browser and nothing is uploaded.