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How Can I make this touch Slider move atomically?

I am trying to make this touch slider, which move between slides automatically.
I tried many ways but nothing helped, this bellow is my Code:
.slider-container {
height: 100vh;
display: inline-flex;
overflow: hidden;
scrollbar-width: none;
transform: translateX(0);
will-change: transform;
transition: transform 0.3s ease-out;
cursor: grab;
}
.slide{
max-height: 100vh;
width: 100vw;
display: flex;
align-items: center;
justify-content: center;
padding: 1rem;
}
<div class="slider-container">
<div class="slide">
<img src="pics/slider/127616685-multi-colored-samples-of-marble-granite-and-travertine-chips-and-pebbles-for-landscape-design-close-.jpg"/>
</div>
<div class="slide">
<img src="pics/slider/1554689647283.jpg"/>
</div>
</div>

Just add this code at the bottom of your JS code.
This code changes the value of currentTranslate every 1 second and then calls the touchEnd(); function.
**I added the variable "loop" if the value is true when the last slide is reached... the script will call the first one again and so on indefinitely. If it has a value of false when the last slide is reached, the interval will be removed. And scrolling the slides will stop.
var loop = true; //<-- "true" Loop or "false" Stop on the End
var slideShw = setInterval(() => {
currentTranslate = currentTranslate - 101;
touchEnd();
if (currentIndex === slides.length - 1) {
if (loop) {
currentIndex -= slides.length;
} else {
stop_slideShw();
}
}
}, 1000);
function stop_slideShw() {
clearInterval(slideShw);
}
Example:
// get our elements
const slider = document.querySelector('.slider-container'),
slides = Array.from(document.querySelectorAll('.slide'))
// set up our state
let isDragging = false,
startPos = 0,
currentTranslate = 0,
prevTranslate = 0,
animationID,
currentIndex = 0
// add our event listeners
slides.forEach((slide, index) => {
const slideImage = slide.querySelector('img')
// disable default image drag
slideImage.addEventListener('dragstart', (e) => e.preventDefault())
// touch events
slide.addEventListener('touchstart', touchStart(index))
slide.addEventListener('touchend', touchEnd)
slide.addEventListener('touchmove', touchMove)
// mouse events
slide.addEventListener('mousedown', touchStart(index))
slide.addEventListener('mouseup', touchEnd)
slide.addEventListener('mousemove', touchMove)
slide.addEventListener('mouseleave', touchEnd)
})
// make responsive to viewport changes
window.addEventListener('resize', setPositionByIndex)
// // prevent menu popup on long press
// window.oncontextmenu = function (event) {
// event.preventDefault()
// event.stopPropagation()
// return false
// }
function getPositionX(event) {
return event.type.includes('mouse') ? event.pageX : event.touches[0].clientX
}
// use a HOF so we have index in a closure
function touchStart(index) {
return function (event) {
currentIndex = index
startPos = getPositionX(event)
isDragging = true
animationID = requestAnimationFrame(animation)
slider.classList.add('grabbing')
}
}
function touchMove(event) {
if (isDragging) {
const currentPosition = getPositionX(event)
currentTranslate = prevTranslate + currentPosition - startPos
}
}
var movedBy;
function touchEnd() {
cancelAnimationFrame(animationID)
isDragging = false
movedBy = currentTranslate - prevTranslate
// if moved enough negative then snap to next slide if there is one
if (movedBy < -100 && currentIndex < slides.length - 1) currentIndex += 1
// if moved enough positive then snap to previous slide if there is one
if (movedBy > 100 && currentIndex > 0) currentIndex -= 1
setPositionByIndex()
slider.classList.remove('grabbing')
}
function animation() {
setSliderPosition()
if (isDragging) requestAnimationFrame(animation)
}
function setPositionByIndex() {
currentTranslate = currentIndex * -window.innerWidth
prevTranslate = currentTranslate
setSliderPosition()
}
function setSliderPosition() {
slider.style.transform = `translateX(${currentTranslate}px)`
}
// NEW LINES /////////////////////////////////////////
var loop = true; //<-- "true" Loop or "false" Stop on the End
var slideShw = setInterval(() => {
currentTranslate = currentTranslate - 101;
touchEnd();
if (currentIndex === slides.length - 1) {
if (loop) {
currentIndex -= slides.length;
} else {
stop_slideShw();
}
}
}, 1000);
function stop_slideShw() {
clearInterval(slideShw);
}
/* :root {
--shadow: rgba(0, 0, 0, 0.8)
}
* {
box-sizing: border-box;
padding: 0;
margin: 0;
}
*/
.slider-container {
height: 100vh;
display: inline-flex;
overflow: hidden;
scrollbar-width: none;
transform: translateX(0);
will-change: transform;
transition: transform 0.3s ease-out;
cursor: grab;
}
.slide {
max-height: 100vh;
width: 100vw;
display: flex;
align-items: center;
justify-content: center;
padding: 1rem;
}
#media(min-width: 1200px) {
.slide {
padding: 3rem;
}
}
.slide img {
max-width: 100%;
max-height: 100%;
transition: transform 0.3s ease-in-out;
box-shadow: 5px 5px 50px -1px var(--shadow);
border-radius: 4px;
user-select: none;
}
.grabbing {
cursor: grabbing;
}
.grabbing .slide img {
transform: scale(0.9);
box-shadow: 5px 5px 40px -1px var(--shadow);
}
<div class="slider-container">
<div class="slide">
<img
src="https://images.pexels.com/photos/145939/pexels-photo-145939.jpeg?auto=compress&cs=tinysrgb&dpr=3&h=750&w=1260" />
</div>
<div class="slide">
<img
src="https://images.pexels.com/photos/47547/squirrel-animal-cute-rodents-47547.jpeg?auto=compress&cs=tinysrgb&dpr=2&h=650&w=940" />
</div>
<div class="slide">
<img
src="https://thumbor.forbes.com/thumbor/960x0/https%3A%2F%2Fspecials-images.forbesimg.com%2Fimageserve%2F5faad4255239c9448d6c7bcd%2FBest-Animal-Photos-Contest--Close-Up-Of-baby-monkey%2F960x0.jpg%3Ffit%3Dscale" />
</div>
</div>

To move your slider automatically you should use the animation property.

Its difficult to work on slider without Javascript. I am giving some fresh codes, you can check them and rewrite your codes accordingly.
var photos = ["1.png","2.png","3.png"]
var time = 3000;
var imgTag = document.querySelector("img")
var count = 0;
function changeImg() {
document.slide.src = photos[count];
count++;
if(count==3){
count=0;
imgTag.src = photos[count];
}
else{
imgTag.src = photos[count];
}
console.log("lap");
setTimeout("changeImg()",time);
}
window.onload = changeImg;
function next(){
count++;
time=3000;
if(count==3){
count=0;
imgTag.src = photos[count];
}
else{
imgTag.src = photos[count];
}
console.log("next");
}
function prev(){
count--;
time=3000;
if(count==-1){
count=2;
imgTag.src = photos[count];
}
else{
imgTag.src = photos[count];
}
console.log("prev");
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Stack Overflow</title>
<link rel="stylesheet" href="style.css">
</head>
<body>
<button onclick="prev()">Prev</button>
<img src="1.png" name="slide" alt="" height="300" width="300">
<button onclick="next()">Next</button>
<script type="text/javascript" src="index.js"></script>
</body>
</html>
Put any 3 images named "1.png" "2.png" "3.png". And then run the code. Hopefully it will run, and you will get an idea. Here I have used a setTimeout function that will fire up after 3 seconds to change your slides.
Thank you.

How to make the element stop falling?

Below this text is my code - I am trying to create the chrome dino game, and so far everything is going well, but I have one problem - after the red block jumps, the dino doesn't stop falling down - while it should. I don't understand where my problem is, as I wrote about the same code yesterday and everything worked just fine. The gravity function can be found in the JavaScript under // Gravity.
Notice how it's code is very similar to the jump function, but it doesn't work as good as the jump function. Any help would be appreciated!!!!!
// HTML Elements + Other Variables
const floor1 = document.getElementById("floor1");
const floor2 = document.getElementById("floor2");
const floor3 = document.getElementById("floor3");
const floor4 = document.getElementById("floor4");
const floor5 = document.getElementById("floor5");
const floor6 = document.getElementById("floor6");
const floor7 = document.getElementById("floor7");
const dino = document.getElementById("dino");
const highBird = document.getElementById("highBird");
const lowBird = document.getElementById("lowBird");
const wideCactus = document.getElementById("wideCactus");
const thinCactus = document.getElementById("thinCactus");
let jump = 0;
// Floor Function
setTimeout(function () {
floor1.classList.add("floor1Animation");
}, 0);
setTimeout(function () {
floor2.classList.add("floor2Animation");
}, 1000);
setTimeout(function () {
floor3.classList.add("floor3Animation");
}, 2000);
setTimeout(function () {
floor4.classList.add("floor4Animation");
}, 3000);
setTimeout(function () {
floor5.classList.add("floor5Animation");
}, 4000);
setTimeout(function () {
floor6.classList.add("floor6Animation");
}, 5000);
setTimeout(function () {
floor7.classList.add("floor7Animation");
}, 6000);
// Jump
document.onkeydown = function (event) {
let key = event.key;
if (key == "ArrowUp") {
let jumpCount = 0;
if (dino.offsetTop == 95) {
let jumpInterval = setInterval(function () {
dino.style.top = (dino.offsetTop - 5) + "px";
jumpCount += 1;
jump = true;
if (jumpCount == 20) {
clearInterval(jumpInterval);
jump = false;
jumpCount = 0;
}
}, 10);
}
}
}
// Gravity
setInterval(function () {
if (jump == false) {
let jumpGravity = setInterval(function () {
dino.style.top = (dino.offsetTop + 5) + "px";
}, 10);
if (dino.offsetTop == 95) {
clearInterval(jumpGravity);
}
}
}, 10);
body {
margin: 0;
padding: 0;
justify-content: center;
align-items: center;
display: flex;
width: 100vw;
height: 100vh;
}
#gameBoard {
width: 1000px;
height: 150px;
border: 2px solid black;
overflow: hidden;
margin: auto;
position: relative;
background-color: white;
}
#dino {
width: 30px;
height: 50px;
background-color: red;
left: 10px;
top: 95px;
position: absolute;
}
.floorBackground {
position: relative;
height: 10px;
width: 200px;
display: flex;
justify-content: center;
align-items: center;
}
.floor {
position: absolute;
top: 140px;
height: 10px;
width: 200px;
}
#floor1 {
right: -200px;
background-color: red;
}
.floor1Animation {
animation: floorAnimation 6s infinite linear;
}
#floor2 {
right: -200px;
background-color: blue;
}
.floor2Animation {
animation: floorAnimation 6s infinite linear;
}
#floor3 {
right: -200px;
background-color: green;
}
.floor3Animation {
animation: floorAnimation 6s infinite linear;
}
#floor4 {
right: -200px;
background-color: purple;
}
.floor4Animation {
animation: floorAnimation 6s infinite linear;
}
#floor5 {
right: -200px;
background-color: brown;
}
.floor5Animation {
animation: floorAnimation 6s infinite linear;
}
#floor6 {
right: -200px;
background-color: orange;
}
.floor6Animation {
animation: floorAnimation 6s infinite linear;
}
#floor7 {
right: -200px;
background-color: yellow;
}
.floor7Animation {
animation: floorAnimation 6s infinite linear;
}
#keyframes floorAnimation {
from {
right: -200px;
}
to {
right: 1000px;
}
}
#keyframes jumping {
}
<!DOCTYPE html>
<html lang = "en">
<head>
<meta charset = "UTF-8">
<title>
Dino Game
</title>
<link rel = "stylesheet" type = "text/css" href = "DinoCSS.css">
</head>
<body>
<div id = "gameBoard">
<div id = "floor1" class = "floor">
<img src = "Pictures/dinoBackground.PNG" class = "floorBackground">
</div>
<div id = "floor2" class = "floor">
<img src = "Pictures/dinoBackground.PNG" class = "floorBackground">
</div>
<div id = "floor3" class = "floor">
<img src = "Pictures/dinoBackground.PNG" class = "floorBackground">
</div>
<div id = "floor4" class = "floor">
<img src = "Pictures/dinoBackground.PNG" class = "floorBackground">
</div>
<div id = "floor5" class = "floor">
<img src = "Pictures/dinoBackground.PNG" class = "floorBackground">
</div>
<div id = "floor6" class = "floor">
<img src = "Pictures/dinoBackground.PNG" class = "floorBackground">
</div>
<div id = "floor7" class = "floor">
<img src = "Pictures/dinoBackground.PNG" class = "floorBackground">
</div>
<div id = "dino"></div>
<div id = "highBird"></div>
<div id = "lowBird"></div>
<div id = "wideCactus"></div>
<div id = "thinCactus"></div>
</div>
<script type = "text/javascript" src = "DinoJS.js"></script>
</body>
</html>

You should try simplifying your code, it may make the issue easier to find or it may even remove it entirely.
I'd suggest using a velocity system, where every frame you adjust the dino's offsetTop by the dino's current velocity, and then subtract the gravity amount from the dino's current velocity.
This causes the velocity to decrease at a constant rate, but the dino's offsetTop position to decrease at an exponential pace, mimicking real gravity.
Then, to make collision work, just test if the dino is at or above the correct "offsetTop" value before subtracting the gravity. If you find that the dino is below the ground, just set the offsetTop to the ground level and clear the velocity.
I'd also suggest moving your game over to the HTML5 Canvas API, since then you just have to deal with properties of objects rather than DOM element style attributes.
Velocity example with canvas:
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
var x = 10;
var y = 10;
var VelocityX = 0;
var VelocityY = 0;
const gravity = 0.75;
// width and height of the square
var width = 10;
var height = 10;
function animate() {
ctx.clearRect(0, 0, canvas.width, canvas.height); // Clear the canvas
x += VelocityX;
if( x > 500) {
x = 0;
}
if ( y >= 450 ) {
y = 450
VelocityY = 0
} else {
y += VelocityY;
VelocityY += gravity; // Higher values = lower position on canvas
}
ctx.fillRect(x, y, width, height);
}
setInterval(animate, 1000 / 60); // 60 FPS
#canvas {
border: 1px solid black;
}
<canvas id="canvas" width="500" height="500"></canvas>
JSFiddle

how to give fadeout effect to a page in javascript without using jQuery

.. i tried using the code in which the loading will keep on increasing till 100 until a new page will open..
if(loading==90){
preload.style.animation = "fadeOut 2s ease";
}
but its not working

Use css opacity, 1 is full visible, 0 is hidden and 0.5 is half visible.
document.getElementById("yourId").style.opacity = "0.5";

You can append class to preload element
if (window.addEventListener) {
window.addEventListener('load', cool, false);
}
function cool() {
var preload = document.getElementById("preload");
var loading = 0;
var id = setInterval(frame,64);
function frame() {
if(loading == 100) {
clearInterval(id);
// window.open("test1.html","_self");
}
if(++loading == 90){
preload.className = "ld";
}
}
};
#preload {
position: absolute;
display: block;
left: 0;
top: 0;
background: tomato;
width: 100%;
height: 200px;
transition: all 2s ease;
}
.ld {
opacity: 0;
}
<div id="preload"></div>
test string

Get user input for one minute, aggregating score

I'm new to javascript and html, which you can probably tell by my code. I am building a simple login game that will help kids practice logging onto devices at school. I want it to run for 1 minute while the game keeps score.
What I really need is a while loop that tests to see if a minute has passed, and during the minute, aggregates the score, resetting the user input fields each time. Coming from a C++ background, I'm really confusing myself going back and fourth between html and java. Specifically, I need that timer in java, and I need a while loop in game_login_entered that runs for a minute (or, I need said while loop in another java function, where it calls game_login_entered() repeatedly for 1 minute.
Thank you for taking the time to read this messy post. I hope I've been specific enough. Can anyone help me sort this out?
function credentials() {
var real_username = document.getElementById('real_username_field').value;
var un = document.getElementById('real_username');
var real_password = document.getElementById('real_password_field').value;
var pw = document.getElementById('real_password');
var teacher_confirmation = confirm("Check with your teacher. Is this correct?\nUsername: " + real_username + "\nPassword: " + real_password);
if (teacher_confirmation == true) {
//START GAME
//clear old stuff
$('.removeMe').hide();
//start timer (statically set at 60 seconds)
onTimer();
//show the hidden game time form.
$('.gametime').show();
} else {
return;
}
}
function game_login_entered() {
var real_password = document.getElementById('real_password_field').value;
var real_username = document.getElementById('real_username_field').value;
var pw = document.getElementById('game_password_field').value;
var un = document.getElementById('game_username_field').value;
var score = 0;
var multiplier = 1;
document.getElementById("game_password_field").style.borderColor = "gray";
document.getElementById("game_username_field").style.borderColor = "gray";
var x = 0;
if (pw == real_password && un == real_username) {
document.getElementById("user_feedback1").innerHTML = "CORRECT!";
document.getElementById("user_feedback2").innerHTML = "";
score = score + (100 * multiplier);
multiplier = multiplier + 1;
} else if (pw != real_password && un != real_username) {
document.getElementById("game_username_field").style.borderColor = "red";
document.getElementById("user_feedback1").innerHTML = "\nIncorrect username.\nEnter: " + real_username;
document.getElementById("game_password_field").style.borderColor = "red";
document.getElementById("user_feedback2").innerHTML = "\nIncorrect password.\nEnter: " + real_password;
multiplier = 1;
} else if (pw != real_password) {
document.getElementById("user_feedback1").innerHTML = "\nIncorrect password.\nEnter: " + real_password;
document.getElementById("game_username_field").style.borderColor = "gray";
document.getElementById("game_password_field").style.borderColor = "red";
document.getElementById("user_feedback2").innerHTML = "";
multiplier = 1;
} else if (un != real_username) {
document.getElementById("user_feedback1").innerHTML = "\nIncorrect username.\nEnter: " + real_username;
document.getElementById("game_username_field").style.borderColor = "red";
document.getElementById("game_password_field").style.borderColor = "gray";
document.getElementById("user_feedback2").innerHTML = "";
multiplier = 1;
}
document.getElementById("user_feedback_score").innerHTML = "Score: " + score;
document.getElementById("user_feedback_multiplier").innerHTML = "Multiplier: " + multiplier;
}
Body {
font-family: Calibri;
background-color: #3399FF;
color: #FFFFFF;
font-size: 18pt;
}
body {
font-size: 1.2em;
}
body input,
body button {
font-size: 1.2em;
}
form > div {
margin: 1em;
}
form button {
margin-left: auto;
margin-right: auto;
width: 50%;
}
label {
display: block;
}
input {
width: 50%;
padding: 0.2em;
}
button {
margin-left: auto;
margin-right: auto;
padding: 0.2em;
}
/*
Blinker
I'm not sure how this works, but hopefully it will allow me to blink the timer */
<style type="text/css"> .blink_text {
-webkit-animation-name: blinker;
-webkit-animation-duration: 1s;
-webkit-animation-timing-function: linear;
-webkit-animation-iteration-count: infinite;
-moz-animation-name: blinker;
-moz-animation-duration: 1s;
-moz-animation-timing-function: linear;
-moz-animation-iteration-count: infinite;
animation-name: blinker;
animation-duration: 1s;
animation-timing-function: linear;
animation-iteration-count: infinite;
color: red;
}
#-moz-keyframes blinker {
0% {
opacity: 1.0;
}
50% {
opacity: 0.0;
}
100% {
opacity: 1.0;
}
}
#-webkit-keyframes blinker {
0% {
opacity: 1.0;
}
50% {
opacity: 0.0;
}
100% {
opacity: 1.0;
}
}
#keyframes blinker {
0% {
opacity: 1.0;
}
50% {
opacity: 0.0;
}
100% {
opacity: 1.0;
}
}
</style>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<h1 id="title" style="blink_text" align="center">Loginator!</h1>
<fieldset class=r emoveMe>
<legend>First, enter your BCPS One username and password:</legend>
<label>Username:
<input type="text" class=r emoveMe id="real_username_field" />
</label>
<br />
<label>Password:
<input type="text" class=r emoveMe id="real_password_field" />
</label>
<br />
<input type="submit" class=r emoveMe id="mySubmit" value="Submit" onclick="credentials()" class=r emoveMe/>
</fieldset>
<br />
<p1 class=r emoveMe><var id="real_username" class=r emoveMe></p1>
<br />
<p1 class = removeMe><var id="real_password" class = removeMe></p1>
<br />
<label class = gametime>Username:<input id="game_username_field" class = gametime></label>
<br />
<label class = gametime>Password: <input id="game_password_field" class = gametime></label>
<br />
<!-- While loop/timer should start here-->
<button id = "button_game_start" onclick="game_login_entered()" class = gametime>log in</button>
<br />
<p3 id = user_feedback1 class = gametime></p3>
<br />
<p3 id = user_feedback2 class = gametime></p3>
<br />
<p3 id = user_feedback_score class = gametime></p3>
<br />
<p3 id = user_feedback_multiplier class = gametime></p3>
<!--This jquery code should make the enter key work when the focus is in the password feild, but it doesn't...-->
<script>
$(#game_password_field).keyup(function(event){
if(event.keyCode == 13){
$(#button_game_start).click();
}
});
</script>
<!--This hides the game form. We will show it in credentials() when the game starts. -->
<script>
$('.gametime').hide();
</script>
<p id="demo"></p>
<!--This button starts the timer. The function is called in credentials(). I would like to put this in the java section so we could customize the timer.-->
<!-- <button onclick="onTimer()">Play!</button> -->
<div id="mycounter" class = gametime></div>
<script>
i = 60;
function onTimer() {
document.getElementById('mycounter').innerHTML = "Time left: " + i;
i--;
if (i < 0) {
alert("Time's up!");
$('.gametime').hide();
return;
}
else {
setTimeout(onTimer, 1000);
}
}
</script>

Since you want to aggregate every minute, use the setInterval function.
var score = 0;
var inputs = document.querySelectorAll("input");
setInterval(function() {
score++;
for (var i = 0; i < inputs.length; i++) {
inputs[i].value = "";
}
},60000);
Here's the updated fiddle
http://jsfiddle.net/b65902mm/1/

javascript css3 change background color every 2 seconds

How can I change the HTML background color automatically every 2 seconds? HTML5 with CSS3 fade in or fadeout?
I tried to use transition with timer and CSS target without any success
input[type=checkbox] {
position: absolute;
top: -9999px;
left: -9999px;
}
label {
display: block;
background: #08C;
padding: 5px;
border: 1px solid rgba(0,0,0,.1);
border-radius: 2px;
color: white;
font-weight: bold;
}
input[type=checkbox]:checked ~ .to-be-changed {
color: red;
}

A few changes A variation on this should work in modern browsers, if you know the colors and the number of colors in advance:
.animate-me {
-webkit-animation: bgcolorchange 4s infinite; /* Chrome, Safari, Opera */
animation: 4s infinite bgcolorchange;
}
#keyframes bgcolorchange {
0% {
background-color: red;
}
25% {
background-color: green;
}
50% {
background-color: yellow;
}
75% {
background-color: yellow;
}
100% {
background-color: red;
}
}
/* Chrome, Safari, Opera */
#-webkit-keyframes bgcolorchange {
0% {background: red;}
25% {background: yellow;}
75% {background: green;}
100% {background: blue;}
}
<div class="animate-me">Trippy! Give me a headache!</div>
http://jsfiddle.net/nnw7xza2/1/
Click to demohere!

Figure it up with:
-css3
-html5
-javascript timer
var arrColor = ["#45c1bf", "#f0593e", "#aeacd4", "#bdd630", "#4479bd", "#f5b11e"];
var footer = document.getElementById("footer");
var header = document.getElementById("header");
//helper function - get dark or lighter color
function LightenDarkenColor(col, amt) {
var usePound = false;
if (col[0] == "#") {
col = col.slice(1);
usePound = true;
}
var num = parseInt(col, 16);
var r = (num >> 16) + amt;
if (r > 255) r = 255;
else if (r < 0) r = 0;
var b = ((num >> 8) & 0x00FF) + amt;
if (b > 255) b = 255;
else if (b < 0) b = 0;
var g = (num & 0x0000FF) + amt;
if (g > 255) g = 255;
else if (g < 0) g = 0;
return (usePound ? "#" : "") + (g | (b << 8) | (r << 16)).toString(16);
}
//random new color
function GetNewColor() {
var index = Math.floor((Math.random() * 5) + 1);
return arrColor[index];
}
// set new color
function SetNewColor(color) {
document.body.style.background = color;
var NewColor = LightenDarkenColor(color, -20);
footer.style.backgroundColor = NewColor;
header.style.backgroundColor = NewColor;
//footer.style.opacity = 1.2;
}
// on document load function start
(function() {
var colorSelected = GetNewColor();
SetNewColor(colorSelected);
})();
//change color timer
window.setInterval(function() {
var colorSelected = GetNewColor();
SetNewColor(colorSelected);
}, 2000);
* {
margin: 0;
padding: 0;
}
body {
background: #bdd630;
transition: background-color 0.5s ease;
color: #fff;
}
#header {
background: #000;
height: 40px;
text-align: center;
}
#content {
/* Now, to activate scrollbars
and compensate #footer height: */
padding-bottom: 40px;
}
#footer {
background: #000;
position: fixed;
bottom: 0px;
width: 100%;
/* cause of fixed pos */
height: 40px;
text-align: center;
}
<div id="header">header</div>
<div id="content">
<p>content here</p>
</div>
<div id="footer">footer</div>
Enjoy

If you are looking for an easy to understand way to do this, check out Basecacti. Of course, Basecacti as of now does not include embedding of the background on to your own html page, so just look at the source code behind it. Here's an example if you need it:
var clr1 = renderColors("clr1");
var clr2 = renderColors("clr2");
var clr3 = renderColors("clr3");
var speed = renderColors("speed");
var deb = document.body;
var circle = 0;
deb.style.backgroundColor = clr1;
setInterval(function(){
if (circle == 0) {
deb.style.backgroundColor = clr2;
circle = 1;
}
else if (circle == 1) {
deb.style.backgroundColor = clr3;
circle = 2;
}
else {
deb.style.backgroundColor = clr1;
circle = 0;
}
}, speed);
To make this work for you, define 3 different colors as clr1, clr2, and clr3. Then set the speed variable to 2000 for 2 secs, and it should work. (The renderColors function that defines these values in the above code is what Basecacti uses to get the colors that users define from a different webpage.) Also, Basecacti is Open-Source for now, so you might want to hurry over to their site and get this code ASAP. If you only want the background to change once after 2 seconds, change the function from setInterval to setTimeout, but don't change anything else. Please comment on this post if the Basecacti website shuts down or stops working, or if I have an error in the code.