diff --git a/README.md b/README.md
index d9753c7..71933b3 100644
--- a/README.md
+++ b/README.md
@@ -85,6 +85,17 @@ If the directory does not exist, you can create it.
 
 If you put a `default.yaml` file in the data directory, PanWriter will merge this with the YAML in your input file (to determine the command-line arguments to call pandoc with) and add the `--metadata-file` option. The YAML should be in the same format as above.
 
+To include CSS in your `default.yaml`, you can also use the same format as in-document metadata, for example:
+
+```yaml
+header-includes: |-
+  <style>
+  blockquote {
+    font-style: italic;
+  }
+  </style>
+```
+
 ### Document types / themes
 
 You can e.g. put `type: letter` in the YAML of your input document. In that case, PanWriter will look for `letter.yaml` instead of `default.yaml` in the user data directory.
diff --git a/electron/dataDir.ts b/electron/dataDir.ts
new file mode 100644
index 0000000..3022a59
--- /dev/null
+++ b/electron/dataDir.ts
@@ -0,0 +1,28 @@
+import { readFile } from 'fs/promises'
+import * as jsYaml from 'js-yaml'
+import { app } from 'electron'
+import { basename, sep } from 'path'
+import { Meta } from '../src/appState/AppState'
+
+export const dataDir = [app.getPath('appData'), 'PanWriterUserData', ''].join(sep)
+
+/**
+ * reads the right default yaml file
+ * make sure this function is safe to expose in `preload.ts`
+ */
+export const readDataDirFile = async (fileName: string): Promise<[Meta | undefined, string]> => {
+  try {
+    // make sure only PanWriterUserData directory can be accessed
+    fileName = dataDir + basename(fileName)
+
+    const str = await readFile(fileName, 'utf8')
+    const yaml = jsYaml.safeLoad(str)
+    return [
+      typeof yaml === 'object' ? (yaml as Meta) : {},
+      fileName
+    ]
+  } catch(e) {
+    console.warn("Error loading or parsing YAML file." + e.message)
+    return [ undefined, fileName ]
+  }
+}
diff --git a/electron/ipc.ts b/electron/ipc.ts
index 85b9e71..daeebfb 100644
--- a/electron/ipc.ts
+++ b/electron/ipc.ts
@@ -1,5 +1,6 @@
 import { BrowserWindow, ipcMain, shell } from 'electron'
 import { Doc } from '../src/appState/AppState'
+import { readDataDirFile } from './dataDir'
 import { Message } from './preload'
 
 // this file contains the IPC functionality of the main process.
@@ -25,6 +26,11 @@ export const init = () => {
   ipcMain.on('openLink', (_event, link: string) => {
     shell.openExternal(link)
   })
+
+  ipcMain.handle('readDataDirFile', async (_event, fileName: string) => {
+    const [ meta ] = await readDataDirFile(fileName)
+    return meta
+  })
 }
 
 export const getDoc = async (win: BrowserWindow): Promise<Doc> => {
diff --git a/electron/pandoc/export.ts b/electron/pandoc/export.ts
index 6048748..321c32c 100644
--- a/electron/pandoc/export.ts
+++ b/electron/pandoc/export.ts
@@ -1,10 +1,8 @@
 import { spawn, SpawnOptionsWithoutStdio } from 'child_process'
-import { app, BrowserWindow, clipboard, dialog } from 'electron'
-import { readFile } from 'fs'
-import * as jsYaml from 'js-yaml'
-import { basename, dirname, extname, sep } from 'path'
-import { promisify } from 'util'
+import { BrowserWindow, clipboard, dialog } from 'electron'
+import { basename, dirname, extname } from 'path'
 import { Doc, JSON, Meta } from '../../src/appState/AppState'
+import { readDataDirFile } from '../dataDir';
 
 interface ExportOptions {
   outputPath?: string;
@@ -25,8 +23,6 @@ declare class CustomBrowserWindow extends Electron.BrowserWindow {
   previousExportConfig?: ExportOptions;
 }
 
-export const dataDir = [app.getPath('appData'), 'PanWriterUserData', ''].join(sep)
-
 export const fileExportDialog = async (win: CustomBrowserWindow, doc: Doc) => {
   const spawnOpts: SpawnOptionsWithoutStdio = {}
   const inputPath = doc.filePath
@@ -95,11 +91,11 @@ const fileExport = async (win: BrowserWindow, doc: Doc, exp: ExportOptions) => {
   const type = typeof docMeta.type === 'string'
     ? docMeta.type
     : 'default'
-  const [extMeta, fileArg] = await defaultMeta(type)
-  const out = mergeAndValidate(docMeta, extMeta, exp.outputPath, exp.toClipboardFormat)
+  const [extMeta, fileName] = await readDataDirFile(type + '.yaml')
+  const out = mergeAndValidate(docMeta, extMeta || {}, exp.outputPath, exp.toClipboardFormat)
 
   const cmd  = 'pandoc'
-  const args = fileArg.concat( toArgs(out) )
+  const args = (extMeta ? ['--metadata-file', fileName] : []).concat( toArgs(out) )
   const cmdDebug = cmd + ' ' + args.map(a => a.includes(' ') ? `'${a}'` : a).join(' ')
   let receivedError = false
 
@@ -224,27 +220,6 @@ const mergeAndValidate = (docMeta: Meta, extMeta: Meta, outputPath?: string, toC
   return out;
 }
 
-/**
- * reads the right default yaml file
- */
-const defaultMeta = async (type: string): Promise<[Meta, string[]]> => {
-  try {
-    const [str, fileName] = await readDataDirFile(type, '.yaml');
-    const yaml = jsYaml.safeLoad(str)
-    return [ typeof yaml === 'object' ? (yaml as Meta) : {}, ['--metadata-file', fileName] ]
-  } catch(e) {
-    console.warn("Error loading or parsing YAML file." + e.message);
-    return [ {}, [] ];
-  }
-}
-
-// reads file from data directory, throws exception when not found
-const readDataDirFile = async (type: string, suffix: string) => {
-  const fileName = dataDir + type + suffix
-  const str = await promisify(readFile)(fileName, 'utf8')
-  return [str, fileName]
-}
-
 // constructs commandline arguments from object
 const toArgs = (out: Out) => {
   const args: string[] = [];
diff --git a/electron/preload.ts b/electron/preload.ts
index 752fe30..c1732f3 100644
--- a/electron/preload.ts
+++ b/electron/preload.ts
@@ -1,5 +1,5 @@
 import { contextBridge, ipcRenderer } from 'electron'
-import { AppState, Doc, ViewSplit } from '../src/appState/AppState'
+import { AppState, Doc, Meta, ViewSplit } from '../src/appState/AppState'
 import { Action } from '../src/appState/Action'
 
 export type IpcApi = typeof ipcApi
@@ -33,6 +33,9 @@ ipcRenderer.on('dispatch', (_e, action: Message) => {
   }
 })
 
+const readDataDirFile = async (fileName: string): Promise<Meta | undefined> =>
+  ipcRenderer.invoke('readDataDirFile', fileName)
+
 const ipcApi = {
   setStateAndDispatch: (s: AppState, d: Disp) => {
     state = s
@@ -54,6 +57,7 @@ const ipcApi = {
   , printFile:        (cb: () => void)          => ipcRenderer.on('printFile',        cb)
   , sendPlatform:     (cb: (p: string) => void) => ipcRenderer.once('sendPlatform',   (_e, p) => cb(p))
   }
+, readDataDirFile
 }
 
 contextBridge.exposeInMainWorld('ipcApi', ipcApi)
diff --git a/src/components/MetaEditor/MetaEditor.tsx b/src/components/MetaEditor/MetaEditor.tsx
index a33ce61..c0245e5 100644
--- a/src/components/MetaEditor/MetaEditor.tsx
+++ b/src/components/MetaEditor/MetaEditor.tsx
@@ -1,7 +1,7 @@
 import { Fragment } from 'react'
 import { AppState }    from '../../appState/AppState'
 import { Action }   from '../../appState/Action'
-import { defaultVars } from '../../renderPreview/templates/getCss'
+import { defaultVars, stripSurroundingStyleTags } from '../../renderPreview/templates/getCss'
 import { ColorPicker } from '../ColorPicker/ColorPicker'
 
 import back from './back.svg'
@@ -164,7 +164,7 @@ const layoutKvs: Kv[] = [{
   name: 'header-includes'
 , label: 'Include CSS'
 , type: 'textarea'
-, onLoad: s => s.startsWith('<style>\n') && s.endsWith('\n</style>') ? s.slice(8, -9) : s
+, onLoad: stripSurroundingStyleTags
 , onDone: s => `<style>\n${s}\n</style>`
 , placeholder: `blockquote {
   font-style: italic;
diff --git a/src/renderPreview/renderPreviewImpl.ts b/src/renderPreview/renderPreviewImpl.ts
index ac9e54a..040ac1e 100644
--- a/src/renderPreview/renderPreviewImpl.ts
+++ b/src/renderPreview/renderPreviewImpl.ts
@@ -114,7 +114,7 @@ const renderAndSwap = async (
 export const renderPlain = async (doc: Doc, previewDiv: HTMLDivElement): Promise<Window> => {
   const { contentWindow } = await setupSingleFrame(previewDiv);
   const content = [
-          '<style>', getCss(doc), '</style>'
+          '<style>', await getCss(doc), '</style>'
         , doc.meta['header-includes']
         , doc.html
         ].join('')
@@ -156,7 +156,7 @@ const pagedjsStyleEl = createStyleEl(`
 export const renderPaged = async (doc: Doc, previewDiv: HTMLDivElement): Promise<Window> => {
   return renderAndSwap(previewDiv, async frameWindow => {
 
-    const cssStr     = getCss(doc)
+    const cssStr     = await getCss(doc)
         , metaHtml   = doc.meta['header-includes']
         , content    = doc.html
         , frameHead  = frameWindow.document.head
diff --git a/src/renderPreview/templates/getCss.ts b/src/renderPreview/templates/getCss.ts
index 320307a..81052f6 100644
--- a/src/renderPreview/templates/getCss.ts
+++ b/src/renderPreview/templates/getCss.ts
@@ -7,5 +7,27 @@ const template = parseToTemplate(styles)
 
 export const defaultVars = extractDefaultVars(template)
 
-export const getCss = (doc: Doc) =>
-  interpolateTemplate(template, doc.meta)
+let headerIncludes = ''
+let docType: string | undefined
+const getHeaderIncludesCss = async (doc: Doc): Promise<string> => {
+  let newDocType = doc.meta.type
+  if (typeof newDocType !== 'string') {
+    newDocType = 'default'
+  }
+  if (newDocType !== docType && window.ipcApi) {
+    // cache css
+    docType = newDocType
+    const meta = await window.ipcApi.readDataDirFile(docType + '.yaml')
+    const field = meta?.['header-includes']
+    headerIncludes = typeof field === 'string'
+      ? stripSurroundingStyleTags(field)
+      : ''
+  }
+  return headerIncludes
+}
+
+export const getCss = async (doc: Doc): Promise<string> =>
+  interpolateTemplate(template, doc.meta) + (await getHeaderIncludesCss(doc))
+
+export const stripSurroundingStyleTags = (s: string): string =>
+  s.startsWith('<style>\n') && s.endsWith('\n</style>') ? s.slice(8, -9) : s