Tidalpunk is solarpunk's ocean-facing offshoot — a speculative design movement imagining seasteads, partially-submerged coastal cities, and hydropower-driven settlements built not against the rising sea but with it. Materials come from recycled ocean plastic and bioengineered seaweed, following real-world experiments like Studio Kathryn Larsen's seaweed bioconcrete and Notpla's algae-based packaging.

Where cyberpunk is neon dread and solarpunk is golden daylight optimism, Tidalpunk is submerged and humanist: a deep teal-navy water column lit from within by a warm, hopeful glow, threaded with seaweed-green currents. It renders technology as buoyant, rounded, and alive rather than sharp and industrial.