code { font-family: Consolas,"courier new"; color: crimson; background-color: rgba(0, 0, 0, 0.2); padding: 2px; font-size: 105%; } apt install linux-source-5.10.12-current-rockchip64 headers seem missing....   Edit: Just lacking a bit behind. Update kernel and get matchin headers for it: code { font-family: Consolas,"courier new"; color: crimson; background-color: rgba(0, 0, 0, 0.2); padding: 2px; font-size: 105%; } apt update &&