User agf1997 is trying to customize the desktop chat window in full-screen mode by injecting custom CSS. Despite trying various file locations within their theme (my_theme/desktop/chat.scss, my_theme/desktop/chat_desktop.scss, my_theme/common/chat.scss, and my_theme/common/chat_desktop.scss), none seem to override the default CSS.
agf1997 shared their CSS code, which aims to adjust the full-screen chat appearance.
After some discussion about the correct file structure, awesomerobot advised that the CSS can be placed in theme/desktop/desktop.scss to impact the chat, as long as the relevant classes are targeted. merefield also suggested using @import "chat" to import chat-specific styles into the main file.
Sorry for the confusion. In the OP I was trying to communicate what files I tried making, and the locations in which I placed them. I don’t want to name the chat mode differently, I’m just trying to figure out which scss file I should place the css in to effect only the desktop, full screen mode chat.
You can put your CSS in theme/desktop/desktop.scss — to impact chat it doesn’t have to be in a chat-specific file, you just have to target the relevant classes.