the problem is when I put .show instead of.box.show in CSS
the even boxes don’t come from the left side.
I just wanna know why? because I thought they were the same thing.
but it seems like in this code they are behaving differently.
const boxes = document.querySelectorAll('.box');
window.addEventListener('scroll',()=>{
const triggerPoint=window.innerHeight*4/5;
boxes.forEach((box)=>{
const boxTop=box.getBoundingClientRect().top;
if(boxTop<triggerPoint){
box.classList.add('show')
}else{
box.classList.remove('show')
}
})
})*{
padding:0;
margin:0;
box-sizing: border-box;
}
body{
background-color: #efedd6;
min-height: 100%;
width:100%;
display:flex;
justify-content: center;
align-items: center;
flex-direction: column;
overflow-x: hidden;
}
.box{
width: 100px;
height: 100px;
background-color: rgb(226, 43, 43);
margin:10px;
transform: translateX(4000%);
transition:0.4s;
}
h1{
margin:10px;
}
.box:nth-of-type(even){
transform: translateX(-4000%);
}
.box.show{
transform: translateX(0%);
transition: .4s;
}<!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">
<link rel="stylesheet" href="style.css">
<title>Scroll Animation</title>
</head>
<body>
<!-- <h1>scroll to see the Animation</h1> -->
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<script src="main.js"></script>
</body>
</html>Advertisement
Answer
.classA targets elements with CSS classclassA and has a CSS specificity of 0, 0, 1, 0. Let’s say 10.
classA.classB (or .classB.classA) targets elements with both classes classA and classB. This time with a specificity of 20 (two classes).
Why does this strange word matter in your case?
Your selector with default transform value below has a specificity of 10:
.box{
transform: translateX(4000%);
}
The following selector
.box:nth-of-type(even){
transform: translateX(-4000%);
}
has a specificity of 20, and will override same CSS attributes from selectors with lower specificity. So your even animation works by overriding .box{transform: translateX(4000%);}.
But .show{ transform: translateX(0%); } doesn’t have a higher specificity, so it can fail to override the original value.
.box.show{transform: translateX(0%);} however, has specificity of 20 and will definitely override the original value just like the selector for even elements.
Read more about specificity with illustrations here: specifics-on-css-specificity