Choose a reading theme and make it your own

Choose a theme for the environment in which you read. Compare the same text, table and diagram before judging a palette by its background alone.

Compare 15 reader themes

Compare iPad captures of the same Coastal snapshot document. Select an image to inspect it at a readable size. A theme changes presentation; the Markdown source remains the same.

Change the document theme

Use the palette / Theme control below the reader pane. Narrow layouts collect it in Reader Tools; on iPhone and iPad, use the appearance controls or Settings → Appearance. App appearance follows System, Light or Dark separately from the selected reader theme.

Set comfortable typography

Adjust reading font, size, line spacing, width and zoom for the screen. Reader font choices also apply to Visual editing; Markdown source has its own editing settings. Check code, muted captions and link contrast as well as body text.

Import a custom JSON theme

Open Settings → Advanced → Custom theme → Import Theme…. Alternatively, open Theme definition, edit the JSON and use Validate and Apply Theme. This version 1 contract accepts defined colors, approved font choices, spacing and borders. It does not apply arbitrary CSS, scripts or layout rules.

{
  "version": 1,
  "background": "#F4F1E9",
  "foreground": "#242424",
  "accent": "#77580D",
  "border": "#D6D0C2",
  "codeBackground": "#E9E2D2",
  "font": "avenirNext",
  "lineHeight": 1.6,
  "paragraphSpacing": 16,
  "contentWidth": 760,
  "borderWidth": 1
}

Keep all fields. Colors use six-digit hex values; font is avenirNext, system, serif or monospaced. Valid ranges: lineHeight 1.2–2.2, paragraphSpacing 0–40, contentWidth 360–1200 and borderWidth 0–3. Unknown fields are rejected.

Reset deliberately

Try a built-in theme first if a custom definition is difficult to read. Reset Reading & Appearance Settings resets more than the current palette, including relevant fonts, width, zoom and Markdown parsing. It preserves documents, opening defaults, saved layouts and sync preferences. Read the confirmation before using it.