Just put a led light or a led strip inside of the box.
I used a led strip like this:
https://it.aliexpress.com/item/1005004585867911.html?spm=a2g0o.productlist.main.65.33714e3f4hpyN3&algo_pvid=9d00bc90-76cc-483c-9db9-d809e23fe305&aem_p4p_detail=2024010711253811545059392306080004640876&algo_exp_id=9d00bc90-76cc-483c-9db9-d809e23fe305-32&pdp_npi=4%40dis%21EUR%2114.11%215.15%21%21%2115.09%21%21%402103835c17046555385142890e5d90%2112000034186328130%21sea%21IT%210%21AB&curPageLogUid=b6XxLMXJlaT9&search_p4p_id=2024010711253811545059392306080004640876_33