CSS has font fallback; so its good practice to include serif, sans, or monospace as the last in the list of fonts to try:

  p, h1, h2, h3, h4, h5, h7, {
    font-family: "Times New Roman", "Times", "Liberation Serif", "Noto Serif", serif
  }

But what about monospace text like source code and when line endings should be preserved; this is the default:

  code, pre {
    font-family: monospace
  }