function solve () {
  let counter = 0
  let selectionCounter = 3
  let buttons = Array.from(document.querySelectorAll('.answer-text'))
  buttons.forEach(b => b.addEventListener('click', getAnswer))
  let allSections = Array.from(document.querySelectorAll('section'))
  let sectionIndex = 0
  function getAnswer () {
    allSections[sectionIndex].style.display = 'none'
    if (
      (sectionIndex === 0 && this.textContent === 'onclick') ||
      (sectionIndex === 1 && this.textContent === 'JSON.stringify()') ||
      (sectionIndex === 2 &&
        this.textContent === 'A programming API for HTML and XML documents')
    ) {
      counter++
    }

    if (sectionIndex < selectionCounter - 1) {
      allSections[sectionIndex + 1].style.display = 'block'
    }

    sectionIndex++

    if (sectionIndex === 3) {
      document.querySelector('#results').style.display = 'block'
      let result = document.querySelector('#results h1')
      result.textContent =
        counter === 3
          ? 'You are recognized as top JavaScript fan!'
          : `You have ${counter} right answers`
    }
  }
}