[ASK] how to make subreddit as landing page

I found a few subreddit turn into landing page when i open it using anonymox addon(proxy) since i cant open reditt from my country

anyone know how to make /edit subreddit stylesheet and turn it into a landing page for CPA

for example this subreddit, /r/TransluCentduck/

i tried a few days to copy stylesheet,etc but not success

anyone know how to do that ?