I wonder how youtubers can get such a layout between two bots

I saw this from a ChessNuke video between Patrick (from Bikini bottom Chess) and Worstbot (which im not sure how he could have simulated it as worstfish is not on chess.com)

Custom CSS (or inspect element) on the client side and then just made the moves on the vs Computers

how do i do that tho, I don't get how he can just slap on Patrick vs Worstfish, and how do I find custom css for the client side

Ok i now understand what this means, but how is Patrick's name and Worstfish's name available with a profile picture for their bot and how is Patrick given the GM sign and Worstfish the BOT sign

tbh theres also just editing the footage in a seamless way

They're changing the code to point to different images

Now I know how they did it, they used analysis and then clicked on details, which let you customize the image, the profile pic, the chess title and the ELO of the players in the game