gistfile1.txt

document.addEventListener('DOMContentLoaded', function() {
  const buttons = document.querySelectorAll(".btn");
  buttons.forEach((btn)=>{
    btn.addEventListener('click', (event)=>{
      const id = btn.getAttribute("href");
      const div = document.querySelector(id);
      if(div){
        //hide other dives
        const otherDivs = div.parentNode.querySelectorAll('div[id^="q_"]');
        otherDivs.forEach((other)=>{
	  other.style.display = 'none'
        });
        //show selected div
        div.classList.add('fit');
        div.style.display = 'block';
      }
    }); 
  });
});