🧩 七巧板Tangram
在线七巧板拼图：用两块大三角形、一块中三角形、两块小三角形、一块正方形和一块平行四边形，拼出上方的灰色剪影。拖动拼图块移动，点一下旋转 90°，平行四边形可以翻面，拼图块会自动对齐网格。内置正方形、帆船、蝴蝶结、小鱼等 11 个图形，支持提示和完成记录。Tangram puzzle online: use the seven pieces — two large triangles, a medium triangle, two small triangles, a square and a parallelogram — to fill the grey silhouette. Drag to move, tap to rotate 90° and flip the parallelogram; pieces snap to the grid. Eleven shapes including a square, sailboat, bow tie and fish, with hints and a record of the shapes you have solved.
拖动拼图块，点一下旋转 90°；选中后可用“翻面”按钮或 F 键翻转，R 旋转，方向键微调，Tab 切换拼图块。Drag a piece to move it and tap it to rotate 90°. With a piece selected, use Flip or F to mirror it, R to rotate, the arrow keys to nudge and Tab to pick another piece.
玩法说明与常见问题How to play & FAQ
「七巧板」怎么玩？How do I play Tangram?
七巧板是一种古老的中国拼图：一块正方形被切成七块，可以拼成成百上千种图形。拼的时候所有七块都要用上，不能重叠，也不能超出剪影。先找大三角形的位置往往是关键，因为它们占了整个面积的一半；剩下的小块再去填补空隙。卡住时点“提示”，会帮你放好一块。Tangram is an ancient Chinese puzzle: a square cut into seven pieces that can form hundreds of figures. Every figure uses all seven pieces, with no overlaps and nothing sticking out of the silhouette. Placing the two large triangles is usually the key, since together they cover half the area; the small pieces then fill the gaps. If you get stuck, Hint places one piece for you.
为什么拼图块只能旋转 90°？Why do pieces rotate in 90° steps?
为了让拼图块准确对齐网格、方便在手机上操作，本游戏里的图形都设计成只需要 90° 旋转和翻面就能拼成。So pieces snap precisely to the grid and are easy to handle on a phone; every shape here can be built using only 90° turns and flips.
一个图形只有一种拼法吗？Is there only one solution per shape?
不一定。只要七块都放进剪影、没有重叠和空隙，就算成功，很多图形都有好几种拼法。Not always. Any arrangement that fills the silhouette with all seven pieces and no overlaps or gaps counts, and many shapes have several solutions.
「七巧板」免费吗？需要下载吗？Is Tangram 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.