How Fast?

Develop a bilingual speed comparison race application targeted at curious children and family groups, with core functionality and experience design as follows. First, set a racer selection module that provides 15 optional contestants covering animals and vehicles ranging from snails to rockets, supporting 2 to 4 users to pick contestants for each single race. Build a real-time dynamically scaled canvas race scene, strictly configure each racer to move at its true relative speed in the real world, allowing users to intuitively perceive the huge speed differences between different carriers such as cheetahs, bullet trains and passenger jets. Add automatic rank-ordered finish overlay display after the race ends, pop up interesting corresponding fun facts for each contestant once they cross the finish line in sequence, and set a final results podium page to clearly show the final standings and corresponding specific speed data of each participant. The application needs to support Simplified Chinese and English bilingual switching, integrate clear and age-appropriate sound effects matching different contestants, add complete pause and resume control functions during the race, and implement a local preference saving mechanism that can retain the user's commonly used racer selection preferences across different application sessions, ensuring the overall interaction is simple and smooth, and the visual style is lively and friendly to meet the usage needs of family and child users.