《时空幻境》（英语：Braid）是一部横版过关暨解谜游戏，由独立游戏制作人强纳生·布洛（Jonathan Blow）所制作。该游戏于2008年8月6日在Xbox 360 Live Arcade发行，而Windows版则在2009年4月10日发布。Mac OS X版则由Hothead Games负责移植，于2009年5月20日发售。

游戏谜样的剧情基本上描述了一位叫「提姆」的主角，试图从怪物手中拯救公主的故事。然而深植于情节中流露的种种蛛丝马迹却引起玩家对故事有着各式各样的解读，如有人认为该故事仅是主角与公主一段犹豫不决的感情关系，也有人认为该故事是描述原子弹的开发。《时空幻境》有着典型的横版过关风格：玩家必须操控主角奔跑、跳跃、以及攀爬过一系列由平台组成的关卡，同时解谜退敌。玩家亦可控制游戏中流逝的时间，以「反转」所谓「已」做过的动作，即使在主角不慎丧命后。主角通过使用这些能力一步步照情节发展，并收集组合散落各处的拼图碎片。

A braid (also referred to as a plait) is a complex structure or pattern formed by interlacing three or more strands of flexible material such as textile yarns, wire, or hair. Compared with the process of weaving, which usually involves two separate, perpendicular groups of strands (warp and weft), a braid is usually long and narrow, with each component strand functionally equivalent in zigzagging forward through the overlapping mass of the others. The most common braid is a flat, solid, three-stranded structure. More complex braids can be constructed from an arbitrary number of strands to create a wider range of structures. Braids have been made for thousands of years in many different cultures, and for a variety of uses. Traditionally, the materials used in braids have depended on the indigenous plants and animals available in the local area.