feat(transformer): allow inline CSS styling (#1551)

* feat(transformer): allow inline CSS styling

* Updated docs

* Default to inline: false

* Removed redundant inline: false

docs/advanced/making plugins.md

@@ -27,7 +27,7 @@ The following sections will go into detail for what methods can be implemented f
   - `cfg`: The full Quartz [[configuration]]
   - `allSlugs`: a list of all the valid content slugs (see [[paths]] for more information on what a `ServerSlug` is)
 - `StaticResources` is defined in `quartz/resources.tsx`. It consists of
-  - `css`: a list of URLs for stylesheets that should be loaded
+  - `css`: a list of CSS style definitions that should be loaded. A CSS style is described with the `CSSResource` type which is also defined in `quartz/resources.tsx`. It accepts either a source URL or the inline content of the stylesheet.
   - `js`: a list of scripts that should be loaded. A script is described with the `JSResource` type which is also defined in `quartz/resources.tsx`. It allows you to define a load time (either before or after the DOM has been loaded), whether it should be a module, and either the source URL or the inline content of the script.
 
 ## Transformers
@@ -85,8 +85,10 @@ export const Latex: QuartzTransformerPlugin<Options> = (opts?: Options) => {
       if (engine === "katex") {
         return {
           css: [
-            // base css
-            "https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.16.9/katex.min.css",
+            {
+              // base css
+              content: "https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.16.9/katex.min.css",
+            },
           ],
           js: [
             {

quartz/components/Head.tsx

@@ -1,6 +1,6 @@
 import { i18n } from "../i18n"
 import { FullSlug, joinSegments, pathToRoot } from "../util/path"
-import { JSResourceToScriptElement } from "../util/resources"
+import { CSSResourceToStyleElement, JSResourceToScriptElement } from "../util/resources"
 import { googleFontHref } from "../util/theme"
 import { QuartzComponent, QuartzComponentConstructor, QuartzComponentProps } from "./types"
 
@@ -40,9 +40,7 @@ export default (() => {
         <link rel="icon" href={iconPath} />
         <meta name="description" content={description} />
         <meta name="generator" content="Quartz" />
-        {css.map((href) => (
-          <link key={href} href={href} rel="stylesheet" type="text/css" spa-preserve />
-        ))}
+        {css.map((resource) => CSSResourceToStyleElement(resource, true))}
         {js
           .filter((resource) => resource.loadTime === "beforeDOMReady")
           .map((res) => JSResourceToScriptElement(res, true))}

quartz/components/renderPage.tsx

@@ -29,7 +29,12 @@ export function pageResources(
   const contentIndexScript = `const fetchData = fetch("${contentIndexPath}").then(data => data.json())`
 
   return {
-    css: [joinSegments(baseDir, "index.css"), ...staticResources.css],
+    css: [
+      {
+        content: joinSegments(baseDir, "index.css"),
+      },
+      ...staticResources.css,
+    ],
     js: [
       {
         src: joinSegments(baseDir, "prescript.js"),

quartz/plugins/transformers/latex.ts

@@ -31,8 +31,10 @@ export const Latex: QuartzTransformerPlugin<Partial<Options>> = (opts) => {
       if (engine === "katex") {
         return {
           css: [
-            // base css
-            "https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.16.9/katex.min.css",
+            {
+              // base css
+              content: "https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.16.9/katex.min.css",
+            },
           ],
           js: [
             {

quartz/util/resources.tsx

@@ -16,6 +16,12 @@ export type JSResource = {
     }
 )
 
+export type CSSResource = {
+  content: string
+  inline?: boolean
+  spaPreserve?: boolean
+}
+
 export function JSResourceToScriptElement(resource: JSResource, preserve?: boolean): JSX.Element {
   const scriptType = resource.moduleType ?? "application/javascript"
   const spaPreserve = preserve ?? resource.spaPreserve
@@ -36,7 +42,24 @@ export function JSResourceToScriptElement(resource: JSResource, preserve?: boole
   }
 }
 
+export function CSSResourceToStyleElement(resource: CSSResource, preserve?: boolean): JSX.Element {
+  const spaPreserve = preserve ?? resource.spaPreserve
+  if (resource.inline ?? false) {
+    return <style>{resource.content}</style>
+  } else {
+    return (
+      <link
+        key={resource.content}
+        href={resource.content}
+        rel="stylesheet"
+        type="text/css"
+        spa-preserve={spaPreserve}
+      />
+    )
+  }
+}
+
 export interface StaticResources {
-  css: string[]
+  css: CSSResource[]
   js: JSResource[]
 }