// Open the Modal
function openModal() {
  document.getElementById("myModal").style.display = "block";
}

// Close the Modal
function closeModal() {
  document.getElementById("myModal").style.display = "none";
}

var slideIndex = 1;
showSlides(slideIndex);

// Next/previous controls
function plusSlides(n) {
  showSlides(slideIndex += n);
}

// Thumbnail image controls
function currentSlide(n) {
  showSlides(slideIndex = n);
}

function showSlides(n) {
  var i;
  var slides = document.getElementsByClassName("mySlides");
  var dots = document.getElementsByClassName("demo");
  var captionText = document.getElementById("caption");
  if (n > slides.length) { slideIndex = 1 }
  if (n < 1) { slideIndex = slides.length }
  for (i = 0; i < slides.length; i++) {
    slides[i].style.display = "none";
  }
  for (i = 0; i < dots.length; i++) {
    dots[i].className = dots[i].className.replace(" img-active", "");
  }
  slides[slideIndex - 1].style.display = "block";
  dots[slideIndex - 1].className += " img-active";
  captionText.innerHTML = dots[slideIndex - 1].alt;
}