<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css">
<body>
<h2 class="w3-center">Manual Slideshow</h2>
<div class="w3-content w3-display-container">
<img class="mySlides1" src="img_snowtops.jpg" style="width:100%">
<img class="mySlides1" src="img_lights.jpg" style="width:100%">
<img class="mySlides1" src="img_mountains.jpg" style="width:100%">
<img class="mySlides1" src="img_forest.jpg" style="width:100%">
<button class="w3-button w3-black w3-display-left" onclick="plusDivs(-1, 0)">❮</button>
<button class="w3-button w3-black w3-display-right" onclick="plusDivs(1, 0)">❯</button>
</div>
<div class="w3-content w3-display-container">
<img class="mySlides2" src="img_la.jpg" style="width:100%">
<img class="mySlides2" src="img_ny.jpg" style="width:100%">
<img class="mySlides2" src="img_chicago.jpg" style="width:100%">
<button class="w3-button w3-black w3-display-left" onclick="plusDivs(-1, 1)">❮</button>
<button class="w3-button w3-black w3-display-right" onclick="plusDivs(1, 1)">❯</button>
</div>
<script>
var slideIndex = [1,1];
var slideId = ["mySlides1", "mySlides2"]
showDivs(1, 0);
showDivs(1, 1);
function plusDivs(n, no) {
showDivs(slideIndex[no] += n, no);
}
function showDivs(n, no) {
var i;
var x = document.getElementsByClassName(slideId[no]);
if (n > x.length) {slideIndex[no] = 1}
if (n < 1) {slideIndex[no] = x.length}
for (i = 0; i < x.length; i++) {
x[i].style.display = "none";