Overrides the theme and applies to the generated image. Use standard CSS; only the properties below apply inside the image.
Classes: .bg (background), .accent-bar (top bar, Accent theme), .bear-face (ʕ•ᴥ•ʔ), .title, .author, .subtitle, .date, .logo (image).
Useful properties: fill (text/shape color), font-size, font-family, font-weight, font-style, text-transform.