The flattened bamboo board (FB) has garnered widespread attention recently due to its ability to enhance bamboo utilization and reduce adhesive consumption. However, FB is primarily composed of three macromolecules: cellulose, hemicellulose, and lignin, making it a flammable material. Meanwhile, FB lacks lateral cell tissues, and its relatively low permeability poses challenges for flame-retardant modification. This work introduces an "H