DOC: Add notebook about custom CSS

doc/custom-css.ipynb

@@ -0,0 +1,151 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Custom CSS\n",
+    "\n",
+    "If you are not satisfied with the CSS styles\n",
+    "provided by `nbsphinx`\n",
+    "and by your Sphinx theme,\n",
+    "don't worry,\n",
+    "you can add your own styles easily."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## For All Pages\n",
+    "\n",
+    "Just create your own CSS file, e.g. `my-own-style.css`,\n",
+    "and put it into the `_static/` sub-directory\n",
+    "of your source directory.\n",
+    "\n",
+    "You'll also have to set the config values\n",
+    "[html_static_path](https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_static_path)\n",
+    "and\n",
+    "[html_css_files](https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_css_files)\n",
+    "in your `conf.py`, e.g. like this:\n",
+    "\n",
+    "```python\n",
+    "html_static_path = ['_static']\n",
+    "html_css_files = ['my-own-style.css']\n",
+    "```"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## For All RST files\n",
+    "\n",
+    "If you want your style to only apply to `*.rst` files\n",
+    "(and not Jupyter notebooks or other source files),\n",
+    "you can use\n",
+    "[rst_prolog](https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-rst_prolog)\n",
+    "with the\n",
+    "[raw](https://docutils.sourceforge.io/docs/ref/rst/directives.html#raw-data-pass-through)\n",
+    "directive in your `conf.py` like this:\n",
+    "\n",
+    "```python\n",
+    "rst_prolog = \"\"\"\n",
+    ".. raw:: html\n",
+    "\n",
+    "    <style>\n",
+    "        h1 {\n",
+    "            color: fuchsia;\n",
+    "        }\n",
+    "    </style>\n",
+    "\"\"\"\n",
+    "```"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## For All Notebooks\n",
+    "\n",
+    "Similarly,\n",
+    "if you want your style to only apply to notebooks,\n",
+    "you can use [nbsphinx_prolog](prolog-and-epilog.ipynb)\n",
+    "like this:\n",
+    "\n",
+    "```python\n",
+    "nbsphinx_prolog = \"\"\"\n",
+    ".. raw:: html\n",
+    "\n",
+    "    <style>\n",
+    "        h1 {\n",
+    "            color: chartreuse;\n",
+    "        }\n",
+    "    </style>\n",
+    "\"\"\"\n",
+    "```"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## For a Single Notebook\n",
+    "\n",
+    "For styles that should affect only the current notebook,\n",
+    "you can simply insert `<style>` tags\n",
+    "into Markdown cells like this:\n",
+    "\n",
+    "```html\n",
+    "<style>\n",
+    "    .nbinput .prompt,\n",
+    "    .nboutput .prompt {\n",
+    "        display: none;\n",
+    "    }\n",
+    "</style>    \n",
+    "```\n",
+    "\n",
+    "<style>\n",
+    "    .nbinput .prompt,\n",
+    "    .nboutput .prompt {\n",
+    "        display: none;\n",
+    "    }\n",
+    "</style>\n",
+    "\n",
+    "This CSS example removes the input and output prompts\n",
+    "from code cells,\n",
+    "see the following cell:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "6 * 7"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.8.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}

doc/index.rst

@@ -18,6 +18,7 @@ was generated from Jupyter notebooks.
     prolog-and-epilog
     custom-formats
     subdir/*
+    custom-css
     a-normal-rst-file
     links
     contributing

doc/usage.ipynb

@@ -138,6 +138,16 @@
     "See also [nbsphinx_codecell_lexer](#nbsphinx_codecell_lexer)."
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### `html_css_files`\n",
+    "\n",
+    "See [Custom CSS](custom-css.ipynb) and\n",
+    "[html_css_files](https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_css_files)."
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},