Waaah - your browser doesn't support scroll-state container queries, upon which much of this game's mechanics rely. You can try CSS Quest out, but won't be able to interact with objects or leave the first map.
Try desktop Chrome for the full experience.
Tips
Use arrow keys to move. Holding them down can be janky, try tapping them instead.
Try not to press tab or esc
Works best in Chrome, sorry. Edge kinda works, but just use Chrome.