footer.html

// templates/footer.html

<style>
  .wrapper {
    position: relative;
    text-align: center;
    top: -4mm;
    width: 100%;
  }
  .wrapper span {
    font-size: 7pt;
  }
</style>
<div class="wrapper">
  <span class="pageNumber"></span>
</div>

generatePDF.js

const fs = require('fs');
const express = require('express');
const puppeteer = require('puppeteer');
const dateTime = require('./lib/getTheFuckingTime');

const app = express();

app.use(express.static('public'));

const server = app.listen(3000, () => {
  console.log('SERVER LISTENING ON http://localhost:3000');
  (async () => {
    const browser = await puppeteer.launch({
      args: ['--no-sandbox', '--disable-setuid-sandbox'],
    });
    try {
      const page = await browser.newPage();
      const footer = fs.readFileSync('./templates/footer.html').toString();
      await page.goto('http://localhost:3000/index.html', {
        waitUntil: 'networkidle0',
      });

      await page.pdf({
        path: `./dist/react-lernen-${dateTime}.pdf`,
        width: '17cm',
        height: '24cm',
        printBackground: true,
        displayHeaderFooter: true,
        headerTemplate: '<span></span>',
        footerTemplate: footer,
      });

      await browser.close();
      server.close();
    } catch (error) {
      console.log(error);
      browser.close();
      server.close();
      process.exit(1);
    }
  })();
});

style.css

/* assets/style.css */

* {
  box-sizing: border-box;
  font-variant-ligatures: none;
}

body {
  font-family: Roboto, Times New Roman, sans-serif;
  font-size: 11pt;
  line-height: 1.65;
  margin: 0;
  padding: 0;
}

/* Working: */
@page {
  size: a4;
  margin: 0.5in 0.25in;
  /* experimental: */
  margin-bottom: 0.75in;
  margin-top: 0.75in;
}

/* This would allow me to include the cover but the pages are all cut off then */
/* @page :first {
  margin: 0;
} */

@page :left {
  margin-right: 0.6in;
}

@page :right {
  margin-left: 0.6in;
}

.chapter {
  margin-left: 0.5in;
  margin-right: 0.5in;
}

.chapter {
  page-break-after: always;
  position: relative;
}

@media screen {
  body {
    font-size: 15pt;
  }
}

@media print {
  body {
    font-size: 11pt;
  }
}

.cover {
  display: none;
  margin: 0;
  /* page-break-after: avoid; */
}

.cover img {
  width: 100vw;
  height: 100vh;
}

pre {
  font-size: 90%;
}

pre,
code {
  font-family: Dank Mono, monospace;
}

h1 {
  display: flex;
  margin: 0px;
  margin-bottom: 24px;
  color: #242a31;
  position: relative;
  margin-top: 32px;
}

h1:before {
  content: ' ';
  position: absolute;
  top: -24px;
  left: 0px;
  height: 1px;
  width: 100%;
  background-color: #e6ecf1;
}

.hljs {
  overflow: hidden !important;
}

pre {
  white-space: pre-wrap;
  overflow: hidden;
}

blockquote {
  border-left: 5px solid #ccc;
  color: #999;
  margin-left: 0;
  padding-left: 1em;
}

.has-image {
  text-align: center;
}

.caption {
  display: block;
  font-size: 85%;
}

@media screen {
  .chapter {
    margin: 1in;
  }

  .cover {
    margin: 0;
    display: none;
  }

  #cover {
    position: relative;
  }

  .hint {
    background-position: 18px 24px;
  }
}

img {
  max-width: 100%;
}

h1, h2, h3 {
  page-break-after: avoid;
}