我的图像轮播无法正常工作？（HTML和CSS）

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("dot");
  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(" active", "");
  }
  slides[slideIndex-1].style.display = "block";
  dots[slideIndex-1].className += " active";
    
    
}

outer {
    display: flex;
    align-items: center;
    justify-content: center;
    animation: slideInRight ease 1s;
}

  @keyframes slideInRight {
  0% {
    opacity: 1;
    transform: translate3d(100%, 0, 0);
  }

  100% {
    opacity: 1;
    transform: none;
  }
}


.wrapper {
    display: grid;
    grid-template-columns: 1fr;
    grid-gap: 100px;
    margin-top: 75px;
    align-content: center;
    text-align: center
}
.element {
    display: grid;
    grid-template-areas: "dsc lgo" "ttl lgo";
    grid-template-rows: auto 1fr;
    grid-template-columns: auto 1fr;
    grid-gap: 10px;
  animation: fadeInAnimation ease 2s;
}
        @keyframes fadeInAnimation { 
            0% { 
                opacity: 0; 
            } 
            
            50% { 
                opacity: 0; 
            } 
            
            100% { 
                opacity: 1; 
            } 
        } 


/* Slideshow container */

.slideshow-container {
  max-width: 1000px;
  position: relative;
  margin: auto;
}

/* Hide the images by default */
.mySlides {
  display: none;
}

/* Next & previous buttons */
.prev, .next {
  cursor: pointer;
  position: absolute;
  top: 50%;
  width: auto;
  margin-top: -22px;
  padding: 16px;
  color: white;
  font-weight: bold;
  font-size: 18px;
  transition: 0.6s ease;
  border-radius: 0 3px 3px 0;
  user-select: none;
}

/* Position the "next button" to the right */
.next {
  right: 0;
  border-radius: 3px 0 0 3px;
}

/* Position the "next button" to the right */
.prev {
  left: 0;
  border-radius: 3px 0 0 3px;
}

/* On hover, add a black background color with a little bit see-through */
.prev:hover, .next:hover {
  background-color: rgba(0,0,0,0.8);
}

/* Caption text */
.text {
  color: #f2f2f2;
  font-size: 15px;
  padding: 8px 0px;
  position: absolute;
  bottom: 8px;
  width: 100%;
  text-align: center;
  background-color: rgba(26, 26, 26, 0.6);
  margin-bottom: 20px;

}

/* The dots/bullets/indicators */
.dot {
  cursor: pointer;
  height: 15px;
  width: 15px;
  margin: 0 2px;
  background-color: #bbb;
  border-radius: 50%;
  display: inline-block;
  transition: background-color 0.6s ease;
}

.active, .dot:hover {
  background-color: #717171;
}

/* Sliding animation */
.fade {
  -webkit-animation-name: fade;
  -webkit-animation-duration: 1.5s;
  animation-name: fade;
  animation-duration: 1.5s;
}

@-webkit-keyframes fade {
  from {opacity: .4}
  to {opacity: 1}
}

@keyframes fade {
  from {opacity: .4}
  to {opacity: 1}
}

    <div class='outer'>
            
                    <div class='wrapper'>
            <div class='element'>
            <!-- Slideshow container -->
<!-- Slideshow container -->
<div class="slideshow-container">

  <!-- Full-width images with number and caption text -->
  <div class="mySlides fade">
    <img src="/images/wallpaper2you_482698.jpg" style="width:100%">
    <div class="text">Caption Text</div>
  </div>

  <div class="mySlides fade">
    <img src="images/wwwallpaper2you_482698.jpg" style="width:100%">
    <div class="text">Caption Two</div>
  </div>

  <div class="mySlides fade">
    <img src="images/wwallpaper2you_482698.jpg" style="width:100%">
    <div class="text">Caption Three</div>
  </div>

  <!-- Next and previous buttons -->
  <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
  <a class="next" onclick="plusSlides(1)">&#10095;</a>
</div>
<br>

<!-- The dots/circles -->
<div style="text-align:center">
  <span class="dot" onclick="currentSlide(1)"></span>
  <span class="dot" onclick="currentSlide(2)"></span>
  <span class="dot" onclick="currentSlide(3)"></span>
</div>
                        </div>
            </div>
    </div>