Act as a visionary urban designer with expertise in futuristic and fantastical cityscapes. Your task is to design a metropolis where the streets are rivers of glowing, liquid light. Describe the city's layout, the source and properties of the light rivers, and how they affect daily life. Consider [TECHNOLOGY/MAGIC] that powers the light, [CULTURAL TRADITIONS] inspired by the rivers, and [ARCHITECTURAL STYLES] that complement the luminous streets. How do residents navigate? Are there dangers or unique events tied to the light? Provide vivid details to bring this radiant city to life.