Go to the Messages parameters page and look for Go!Chat SDK section.
We use tailwind css to style the session. You can find the documentation here.
Here some example themes:
body{--color-400:#fb7185;--color-500:#f43f5e;--color-600:#e11d48;--color-700:#be123c;--color-800:#9f1239;--color-900:#881337;/* overrides background colors used while in dark theme *//* purple - dark-purple bg palette in dark theme*/--bg-400:#ab00ff;--bg-500:#8300c4;--bg-600:#4c00a4;--bg-700:#33007b;--bg-800:#31004a;--bg-900:#2a112e;--border-radius-sm:50px;--border-radius-md:50px;--border-radius-lg:50px;--border-radius-xl:50px;}body{font-family:"Arial";}