Add legibility to old school website content with minimal CSS

main.js

function addStyles() {
  document.body.style.margin = '50px auto';
  document.body.style.maxWidth = '38em'; // 680px

  document.body.style.fontSize = '18px';
  document.body.style.lineHeight = '1.4';
  document.body.style.wordBreak = 'break-word';
  document.body.style.hyphens = 'auto';
}

if(!document.querySelector('link') || !document.querySelector('style')) { // no link/style tags
  addStyles();
}

style.css

body {
	margin: 50px auto;
	max-width: 38em; /* 680px; */
	
	font-size: 18px;
	line-height: 1.4;
	word-break: break-word;
	hyphens: auto;
}