:root:has(#theme-Custom-uiFont[theme-custom_uifont-default="Serif"]) {
    * {font-family: serif !important;}
}
:root:has(#theme-Custom-uiFont[theme-custom_uifont-default="Custom"]) {
    * {font-family: var(--theme-custom_uifont-custom) !important; text-shadow: var(--theme-custom_uifont-shadow) !important;}
}