JSFiddle - React, Tailwind, and code Playground
HTML
<a href='javascript:(function(){var pg=+document.location.pathname.substr(3,2),backtext=document.createTextNode("<< back"),nexttext=document.createTextNode("next >>");if(pg>1){var nextpg=pg-1;nextpg<10&&(nextpg="0"+nextpg);var back="/ex"+nextpg+".html",link=document.createElement("a");link.appendChild(backtext),link.setAttribute("href",back),document.getElementsByTagName("article")[0].appendChild(link)}if(pg<52){var nextpg=pg+1;nextpg<10&&(nextpg="0"+nextpg);var next="/ex"+nextpg+".html",link=document.createElement("a");link.appendChild(nexttext),link.setAttribute("href",next),link.style.float="right",document.getElementsByTagName("article")[0].appendChild(link)}}()); '>Drag to Bookmark bar</a>