Develop Reference

Uncaught TypeError: $ is not a function $('#loader').hide()

I want to add my page to a loading spinner. I want to hide spinner when page loaded. I want to show that when button clicked and i want to hide again when json process is finished. I can't continue because I got an error even in the first step. Here is the code i got in the first step :
Uncaught TypeError: $ is not a function
All HTML, CSS and Javascript codes are below:
window.addEventListener('load', function () {
$('#loader').hide();
})
.loader {
position: absolute;
top: calc(50% - 32px);
left: calc(50% - 32px);
width: 64px;
height: 64px;
border-radius: 50%;
perspective: 800px;
}
.inner {
position: absolute;
box-sizing: border-box;
width: 100%;
height: 100%;
border-radius: 50%;
}
.inner.one {
left: 0%;
top: 0%;
animation: rotate-one 1s linear infinite;
border-bottom: 3px solid green;
}
.inner.two {
right: 0%;
top: 0%;
animation: rotate-two 1s linear infinite;
border-right: 3px solid green;
}
.inner.three {
right: 0%;
bottom: 0%;
animation: rotate-three 1s linear infinite;
border-top: 3px solid green;
}
#keyframes rotate-one {
0% {
transform: rotateX(35deg) rotateY(-45deg) rotateZ(0deg);
}
100% {
transform: rotateX(35deg) rotateY(-45deg) rotateZ(360deg);
}
}
#keyframes rotate-two {
0% {
transform: rotateX(50deg) rotateY(10deg) rotateZ(0deg);
}
100% {
transform: rotateX(50deg) rotateY(10deg) rotateZ(360deg);
}
}
#keyframes rotate-three {
0% {
transform: rotateX(35deg) rotateY(55deg) rotateZ(0deg);
}
100% {
transform: rotateX(35deg) rotateY(55deg) rotateZ(360deg);
}
}
#loading {
width: 100%;
height: 100%;
top: 0;
left: 0;
position: fixed;
display: block;
opacity: 0.7;
background-color: #fff;
z-index: 99;
text-align: center;
}
#loading-image {
position: absolute;
top: 100px;
left: 240px;
z-index: 100;
}
<div id="loading">
<div class="loader">
<div class="inner one"></div>
<div class="inner two"></div>
<div class="inner three"></div>
</div>
</div>
How can i solve this problem ?

it seems like your using Vanilla JS, so you need to use querySelector, or otherwise if you're using jQuery, so you need to call the jQuery library at your header.
so incase your using the Vanila JS so you can call it like this
window.addEventListener('load', function () {
setTimeout( () => {document.querySelector('.loader').style = 'display:none;'}, 2000);
})
.loader {
position: absolute;
top: calc(50% - 32px);
left: calc(50% - 32px);
width: 64px;
height: 64px;
border-radius: 50%;
perspective: 800px;
}
.inner {
position: absolute;
box-sizing: border-box;
width: 100%;
height: 100%;
border-radius: 50%;
}
.inner.one {
left: 0%;
top: 0%;
animation: rotate-one 1s linear infinite;
border-bottom: 3px solid green;
}
.inner.two {
right: 0%;
top: 0%;
animation: rotate-two 1s linear infinite;
border-right: 3px solid green;
}
.inner.three {
right: 0%;
bottom: 0%;
animation: rotate-three 1s linear infinite;
border-top: 3px solid green;
}
#keyframes rotate-one {
0% {
transform: rotateX(35deg) rotateY(-45deg) rotateZ(0deg);
}
100% {
transform: rotateX(35deg) rotateY(-45deg) rotateZ(360deg);
}
}
#keyframes rotate-two {
0% {
transform: rotateX(50deg) rotateY(10deg) rotateZ(0deg);
}
100% {
transform: rotateX(50deg) rotateY(10deg) rotateZ(360deg);
}
}
#keyframes rotate-three {
0% {
transform: rotateX(35deg) rotateY(55deg) rotateZ(0deg);
}
100% {
transform: rotateX(35deg) rotateY(55deg) rotateZ(360deg);
}
}
#loading {
width: 100%;
height: 100%;
top: 0;
left: 0;
position: fixed;
display: block;
opacity: 0.7;
background-color: #fff;
z-index: 99;
text-align: center;
}
#loading-image {
position: absolute;
top: 100px;
left: 240px;
z-index: 100;
}
<div id="loading">
<div class="loader">
<div class="inner one"></div>
<div class="inner two"></div>
<div class="inner three"></div>
</div>
</div>
PS. i'm using Timeout with 2seconds because no thing to load.

It seems like you are using jquery, so make sure you have added <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.1/jquery.min.js"></script> in the head tag.
Also change $('#loader') to $('.loader') because there isn't any div with id loader.

how to create design Letter z with animation in css

I want to create the letter z in animation.
In such a way that the first part (1) appears without delay with animation from left to right.
When the first part (1) reaches the right, the second part (2) will appear from top to bottom with animation.
When the second part (2) is down, the third part (3) will appear from left to right with animation.
The problem with this animation is that all three parts (1-2-3) appear together, while I want them to appear alternately and late.
Thank you in advance for your cooperation.
#global{
width:200px;
position:relative;
cursor:pointer;
height:200px;
background-color: black;
padding: 1rem;
}
.mask{
position:absolute;
border-radius:2px;
overflow:hidden;
perspective: 1000;
backface-visibility: hidden;
}
.plane{
background:#ffffff;
width:400%;
height:100%;
position:absolute;
transform : translate3d(0px,0,0);
z-index:100;
perspective: 1000;
backface-visibility: hidden;
}
#top .plane{
z-index:2000;
animation: trans1 1s ease-in infinite 0s forwards;
-webkit-animation: trans1 1s ease-in infinite 0s forwards;
}
#middle .plane{
transform: translate3d(0px,0,0);
background: #bbbbbb;
animation: trans2 1s linear infinite 2s forwards;
-webkit-animation: trans2 1s linear infinite 2s forwards;
}
#bottom .plane{
z-index:2000;
animation: trans3 2s ease-out infinite 4s forwards;
-webkit-animation: trans3 2s ease-out infinite 4s forwards;
}
#top{
width:200px;
height:15px;
left:0;
z-index:100;
transform: skew(-15deg, 0);
border-radius: 20px;
-webkit-border-radius: 20px;
-moz-border-radius: 20px;
-ms-border-radius: 20px;
-o-border-radius: 20px;
}
#middle{
width:187px;
height:25px;
left:6px;
top:78px;
transform:skew(-15deg, -40deg);
-webkit-transform:skew(-15deg, -40deg);
-moz-transform:skew(-15deg, -40deg);
-ms-transform:skew(-15deg, -40deg);
-o-transform:skew(-15deg, -40deg);
border-radius: 20px;
-webkit-border-radius: 20px;
-moz-border-radius: 20px;
-ms-border-radius: 20px;
-o-border-radius: 20px;
}
#bottom{
width:200px;
height:15px;
top:159px;
transform: skew(-15deg, 0);
-webkit-transform: skew(-15deg, 0);
-moz-transform: skew(-15deg, 0);
-ms-transform: skew(-15deg, 0);
-o-transform: skew(-15deg, 0);
border-radius: 20px;
}
#keyframes trans1{
0% {
width: 0%;
left: 0;
}
100% {
width: 100%;
left: 0;
}
}
#keyframes trans2{
0% {
width: 0%;
left: 100%;
}
100% {
width: 100%;
left: 0;
}
}
#keyframes trans3{
0% {
width: 0%;
left: 0;
}
100% {
width: 100%;
left: 0;
}
}
<div id="global">
<div id="top" class="mask">
<div class="plane"></div>
</div>
<div id="middle" class="mask">
<div class="plane"></div>
</div>
<div id="bottom" class="mask">
<div class="plane"></div>
</div>
</div>

This snippet thinks of things slightly differently.
Each line has a 3 second animation with the top one animating to its full width in the first second, ie the first 33.33% of the time, the second animating to its full width in the second second and the third in the third second.
That way aspects such as the lines not being visible to start with are dealt with.
#global {
width: 200px;
position: relative;
cursor: pointer;
height: 200px;
background-color: black;
padding: 1rem;
}
.mask {
position: absolute;
border-radius: 2px;
overflow: hidden;
perspective: 1000;
backface-visibility: hidden;
}
.plane {
background: #ffffff;
width: 400%;
height: 100%;
position: absolute;
transform: translate3d(0px, 0, 0);
z-index: 100;
perspective: 1000;
backface-visibility: hidden;
}
#top .plane {
z-index: 2000;
animation: trans1 3s ease-in infinite forwards;
}
#middle .plane {
transform: translate3d(0px, 0, 0);
background: #bbbbbb;
animation: trans2 3s linear infinite forwards;
}
#bottom .plane {
z-index: 2000;
animation: trans3 3s ease-out infinite forwards;
}
#top {
width: 200px;
height: 15px;
left: 0;
z-index: 100;
transform: skew(-15deg, 0);
border-radius: 20px;
}
#middle {
width: 187px;
height: 25px;
left: 6px;
top: 78px;
transform: skew(-15deg, -40deg);
border-radius: 20px;
}
#bottom {
width: 200px;
height: 15px;
top: 159px;
transform: skew(-15deg, 0);
border-radius: 20px;
}
#keyframes trans1 {
0% {
width: 0%;
left: 0;
}
33.33% {
width: 100%;
left: 0;
}
100% {
width: 100%;
left: 0;
}
}
#keyframes trans2 {
0% {
width: 0%;
left: 100%;
}
33.33% {
width: 0%;
left: 100%;
}
66.66% {
width: 100%;
left: 0;
}
100% {
width: 100%;
left: 0;
}
}
#keyframes trans3 {
0% {
width: 0%;
left: 0;
}
66.66% {
width: 0%;
left: 0;
}
100% {
width: 100%;
left: 0;
}
}
<div id="global">
<div id="top" class="mask">
<div class="plane"></div>
</div>
<div id="middle" class="mask">
<div class="plane"></div>
</div>
<div id="bottom" class="mask">
<div class="plane"></div>
</div>
</div>

Transform Rotate not working on my CSS when I added keyframes [duplicate]

I have a situation similar to this fiddle, where I have a CSS3 animation that scales an element absolute-positioned in the centre of another element. However, when the animation takes place it is off-centre, as seen by the red squares relative to blue in the example. How do I centre it? I have tried a couple of configurations around the transform-origin property, but this isn't producing the correct results.
#keyframes ripple_large {
0% {transform:scale(1); }
75% {transform:scale(3); opacity:0.4;}
100% {transform:scale(4); opacity:0;}
}
.container {
position: relative;
display: inline-block;
margin: 10vmax;
}
.cat {
height: 20vmax;
}
.center-point {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
height: 10px;
width: 10px;
background: blue;
}
.to-animate {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
border: 1px solid red;
height: 5vmax;
width: 5vmax;
transform-origin:center;
}
.one {
animation: ripple_large 2s linear 0s infinite;
}
.two {
animation: ripple_large 2s linear 1s infinite;
}
<div class='container'>
<img src='http://www.catster.com/wp-content/uploads/2017/08/Pixiebob-cat.jpg' class='cat'>
<div class='center-point'>
</div>
<div class='to-animate one'></div>
<div class='to-animate two'></div>
</div>

The issue is that you are overriding the translate transformation.
When you specify a new transformation (the one inside the animation) it override the first one. In your case you are removing the translation that is fixing the center alignment.
You need to add them to the same transform property and pay attention to the order because it's important (Why does order of transforms matter? rotate/scale doesn't give the same result as scale/rotate)
#keyframes ripple_large {
0% {
transform: translate(-50%, -50%) scale(1);
}
75% {
transform: translate(-50%, -50%) scale(3);
opacity: 0.4;
}
100% {
transform: translate(-50%, -50%) scale(4);
opacity: 0;
}
}
.container {
position: relative;
display: inline-block;
margin: 10vmax;
}
.cat {
height: 20vmax;
}
.center-point {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
height: 10px;
width: 10px;
background: blue;
transform-origin: center;
}
.to-animate {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
border: 1px solid red;
height: 5vmax;
width: 5vmax;
}
.one {
-webkit-animation: ripple_large 2s linear 0s infinite;
animation: ripple_large 2s linear 0s infinite;
}
.two {
-webkit-animation: ripple_large 2s linear 1s infinite;
animation: ripple_large 2s linear 1s infinite;
}
<div class='container'>
<img src='http://www.catster.com/wp-content/uploads/2017/08/Pixiebob-cat.jpg' class='cat'>
<div class='center-point'>
</div>
<div class='to-animate one'></div>
<div class='to-animate two'></div>
</div>
UPDATE
As commented, it's better to center your element using another method than translation to avoid changing the animation since this can be used with other elements.
Example:
#keyframes ripple_large {
0% {
transform: scale(1) ;
}
75% {
transform:scale(3) ;
opacity: 0.4;
}
100% {
transform: scale(4) ;
opacity: 0;
}
}
.container {
position: relative;
display: inline-block;
margin: 10vmax;
}
.cat {
height: 20vmax;
}
.center-point {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
height: 10px;
width: 10px;
background: blue;
transform-origin:center;
}
.to-animate {
position: absolute;
top: 0;
left: 0;
bottom:0;
right:0;
margin:auto;
border: 1px solid red;
height: 5vmax;
width: 5vmax;
}
.one {
animation: ripple_large 2s linear 0s infinite;
}
.two {
animation: ripple_large 2s linear 1s infinite;
}
<div class='container'>
<img src='http://www.catster.com/wp-content/uploads/2017/08/Pixiebob-cat.jpg' class='cat'>
<div class='center-point'>
</div>
<div class='to-animate one'></div>
<div class='to-animate two'></div>
</div>

How to hide the scroll indicator on scroll?

Dear people of the Internet,
I have this css & html code to add an scroll indicator to my landing page.
My goal is; As soon as you scroll down, the indicator disappears and only appears again after reloading the page.
My jquery seems not to work, any help much appreciated!
$(window).scroll(function() {
if ($(this).scrollTop()>0)
{
$('.scrolli').fadeOut();
}
});
body{
margin: 0;
padding: 0;
background: #000;
}
.scrolli{
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%,-50%);
}
.scrolli span{
display: block;
width: 20px;
height: 20px;
border-bottom: 1px solid #FFF;
border-right: 1px solid #FFF;
transform: rotate(45deg);
margin: -10px;
animation: animate 2s infinite;
}
.scrolli span:nth-child(2){
animation-delay: -0.2s;
}
.scrolli span:nth-child(3){
animation-delay: -0.4s;
}
#keyframes animate{
0%{
opacity: 0;
transform: rotate(45deg) translate(-20px,-20px);
}
50%{
opacity: 1;
}
100%{
opacity: 0;
transform: rotate(45deg) translate(20px,20px);
}
}
<div class="scrolli">
<span></span>
<span></span>
<span></span>
</div>

Your code is fine, it doesn't work because there isn't any available scroll, so $(this).scrollTop() can't ever be greater than zero.
You can see it working by making the body taller:
$(window).scroll(function() {
if ($(this).scrollTop()>0)
{
$('.scrolli').fadeOut();
}
});
body{
margin: 0;
padding: 0;
background: #000;
height: 200vh;
}
.scrolli{
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%,-50%);
}
.scrolli span{
display: block;
width: 20px;
height: 20px;
border-bottom: 1px solid #FFF;
border-right: 1px solid #FFF;
transform: rotate(45deg);
margin: -10px;
animation: animate 2s infinite;
}
.scrolli span:nth-child(2){
animation-delay: -0.2s;
}
.scrolli span:nth-child(3){
animation-delay: -0.4s;
}
#keyframes animate{
0%{
opacity: 0;
transform: rotate(45deg) translate(-20px,-20px);
}
50%{
opacity: 1;
}
100%{
opacity: 0;
transform: rotate(45deg) translate(20px,20px);
}
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="scrolli">
<span></span>
<span></span>
<span></span>
</div>

css circle rotation with text inside

Can you guys tell me how to make the hallo text to centre inside the circle?
The circle is not currently working the way it should in IE8 and Firefox.
Does anyone have any ideas / suggestions that could fix this?
I have provided a fiddle
Here is my code below (It is all in my Fiddle above)
CSS
.spinner span em {
border-radius: 999px;
position: absolute;
width: 100%;
height: 100%;
-webkit-animation-iteration-count: infinite;
-webkit-animation-timing-function: linear;
}
.spinner span:first-child em {
left: 100%;
border-top-left-radius: 0;
border-bottom-left-radius: 0;
-webkit-animation-name: rotate-lt;
-webkit-transform-origin: 0 50%;
}
.spinner span:last-child em {
left: -100%;
border-top-right-radius: 0;
border-bottom-right-radius: 0;
-webkit-animation-name: rotate-rt;
-webkit-transform-origin: 100% 50%;
}
HTML
<div class="spinner">
<span><em></em></span>
<span><em></em></span>
hallo
</div>
Any help would be great!

To centre your text, use text-align:center for horizontal alignment, and set line-height:300px (with 300px being equal to the element's height) for vertical alignment.

Check this fiddle, I've placed a wrapper div
HTML
<div class="wrapper">
<div class="spinner">
<span><em></em></span>
<span><em></em></span>
</div>
<div class="text">hallo<div>
</div>
CSS
body {
margin: 50px;
}
.wrapper {
position: relative;
width: 300px;
height: 300px;
margin: 0 auto;
}
.text {
position: absolute;
top:0px;
width: 300px;
height: 300px;
margin: 0 auto;
z-index:10;
text-align:center;
line-height:300px;
}
.spinner {
position: absolute;
width: 300px;
height: 300px;
background: #aaa;
}
.spinner:after {
position: absolute;
content: "";
width: 80%;
height: 80%;
border-radius: 100%;
background: #fff;
top: 10%;
left: 10%;
}
.spinner span em {
background: #0e728e;
-webkit-animation-duration: 3s;
}
/* No need to edit below this line */
#-webkit-keyframes rotate-rt {
0% { -webkit-transform: rotate(0deg); }
25% { -webkit-transform: rotate(180deg); }
50% { -webkit-transform: rotate(180deg); }
75% { -webkit-transform: rotate(360deg); }
100% { -webkit-transform: rotate(360deg); }
}
#-webkit-keyframes rotate-lt {
0% { -webkit-transform: rotate(0deg); }
25% { -webkit-transform: rotate(0deg); }
50% { -webkit-transform: rotate(180deg); }
75% { -webkit-transform: rotate(180deg); }
100% { -webkit-transform: rotate(360deg); }
}
.spinner {
border-radius: 100%;
position: relative;
}
.spinner span {
width: 50%;
height: 100%;
overflow: hidden;
position: absolute;
}
.spinner span:first-child {
left: 0;
}
.spinner span:last-child {
left: 50%;
}
.spinner span em {
border-radius: 999px;
position: absolute;
width: 100%;
height: 100%;
-webkit-animation-iteration-count: infinite;
-webkit-animation-timing-function: linear;
}
.spinner span:first-child em {
left: 100%;
border-top-left-radius: 0;
border-bottom-left-radius: 0;
-webkit-animation-name: rotate-lt;
-webkit-transform-origin: 0 50%;
}
.spinner span:last-child em {
left: -100%;
border-top-right-radius: 0;
border-bottom-right-radius: 0;
-webkit-animation-name: rotate-rt;
-webkit-transform-origin: 100% 50%;
}