function fadeInBackground() {
  document.body.classList.add('fade-in');
}
setTimeout(fadeInBackground, 1000);


function updateDivSize() {
  const divWindow = document.getElementById('divWindow');
  //const divContents = document.getElementById('divContents');
  const windowWidth = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth;
  const windowHeight = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;

  const adjustedWidth = windowWidth - 20;
  const adjustedHeight = windowHeight - 20;

  divWindow.style.width = adjustedWidth + 'px';
  divWindow.style.height = adjustedHeight + 'px';
  //divContents.textContent = `Width: ${adjustedWidth}px, Height: ${adjustedHeight}px`;
}
window.addEventListener('resize', updateDivSize);
updateDivSize();