<body><h1> Welcome to my blog</h1>
 
<div class="slider">
  <div class="indicatorContainer">
  <div id="indicator1"></div>
  <div id="indicator2"></div>
  <div id="indicator3"></div>
  </div>
  <div class="BtnContainer">
  <button class="forward" onclick="setImgIndex(1)"></button>
  <button class="backward" onclick="setImgIndex(-1)"></button>
  </div>
<div class="backgroundimages">
  
  <img  src="https://static.pexels.com/photos/226243/pexels-photo-226243.jpeg" alt="alte Kamera">
   <img  src="https://static.pexels.com/photos/7882/light-bulb-light-old.jpg" alt="Glühbirne">
   <img src="https://static.pexels.com/photos/85886/lamp-finger-touch-hand-85886.jpeg" alt="Finger, der auf Glühbirne zeigt">
 
  
  </div>
  </div></body>
h1 {
  text-align: center;
  text-transform: uppercase;
  color: white;
  padding-bottom: 10px;
  font-size: 40pt;
  font-weight: 100;
  letter-spacing: 4pt;
}

body {
  margin-bottom: 50px;
  font-family: montserrat;
  background: #1f1f1f;
}

.BtnContainer{
  display:flex;
  justify-content:space-between;
  flex-flow: row nowrap;
  width:100%;
}

img {
  height: 500px;
  width: 800px;
}

.indicatorContainer{
  display:flex;
  flex-direction:row;
  justify-content:space-around;
  position:absolute;
  width:70px;
  height:5px;
  left:435px;
  top:615px;
}

#indicator1, #indicator2, #indicator3{
  border:5px solid white;
  border-radius:50%;
  transition: all ease-in-out 0.5s;
  
}

.backgroundimages {

  transition: all ease-in-out 1s;
  display: flex;
  flex-flow: row nowrap;
  justify-content: flex-start;
}

button{
  border-radius:0;
}

button:hover {
  cursor: pointer;
  opacity: 0.8;
}

.slider {
  height: 600px;
  width: 800px;
  overflow: hidden;
  margin: auto;
}

.forward {
  border: 10px solid white;
  background: white
    url("https://d30y9cdsu7xlg0.cloudfront.net/png/755942-200.png") no-repeat;
  opacity: 0.5;
  background-size: contain;
  position: absolute;
  top: 380px;
  margin-left: 750px;
  padding: 15px;
  box-sizing: border-box;
  transition: all 0.2s ease-in-out;
}

.backward {
  overflow: hidden;
  border: 10px solid #fff;
  background: white
    url("https://d30y9cdsu7xlg0.cloudfront.net/png/755953-200.png") no-repeat
    0px;
  background-size: contain;
  color: none;
  opacity: 0.5;
  position: absolute;
  top: 380px;
  padding: 15px;
  box-sizing: border-box;
  transition: all 0.2s ease-in-out;
}

var imgIndex = 0;
var distance = -800;
var imgSelector = document.querySelector(".backgroundimages");
var indicator1Active = document.querySelector("#indicator1");
var indicator2Active = document.querySelector("#indicator2");
var indicator3Active = document.querySelector("#indicator3");
updateIndicators();


function setImgIndex(d) {
  imgIndex = imgIndex + d;
  if (imgIndex > 2) {
    imgIndex = 0;
  } else if (imgIndex < 0) {
    imgIndex = 2;
  }

  imgSelector.style.marginLeft = distance * imgIndex + "px";
  updateIndicators();
}

function updateIndicators() {
  switch (imgIndex) {
    case 1:
      indicator1Active.style.opacity = "0.3";
      indicator2Active.style.opacity = "0.8";
      indicator3Active.style.opacity = "0.3";
      break;
    case 2:
      indicator1Active.style.opacity = "0.3";
      indicator2Active.style.opacity = "0.3";
      indicator3Active.style.opacity = "0.8";
      break;
    default:
      indicator1Active.style.opacity = "0.8";
      indicator2Active.style.opacity = "0.3";
      indicator3Active.style.opacity = "0.3";
      
  }
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.