How to make the mouse hover over the button to display the layer, when the mouse is over the button or layer, the layer does not disappear, if you leave both, it will disappear?

just like the "message", "dynamic" and other buttons at the top of bilibili, a pull-down suspension layer appears when you hover over it. As long as the mouse is still on the button, or on the layer, the layer will not disappear, without both will disappear.

Css html5 html javascript
Mar.20,2021

< style > 

-sharpparent{
    position:relative;
    width:100px;
    height:100px;
    background:-sharpf99;
}
-sharpchildren{
    position: absolute;
    width:100px;
    height:100px;
    right:-100%;
    top:0;
    background:-sharp99f;
    display:none;
}

< / style >
< div id= "parent" > 

<div id="children"></div>

< / div >
< script > 

var eParent = document.getElementById('parent')
var eChildren = document.getElementById('children')

eChildren.onmouseover =  eParent.onmouseover = function(e){
    eChildren.style.display="block"
}
eChildren.onmouseout =  eParent.onmouseout = function(e){
    eChildren.style.display="none"
}

< / script >

Does

mean this?

-Update

< style > 

*{
    margin:0;
    padding:0;
}
ul{
    list-style: none;
}
.item{
    position:relative;
    width:100px;
    height:100px;
    background:-sharpf99;
    border:1px solid -sharpccc;
    cursor:pointer;
}
.item div{
    position: absolute;
    width:100px;
    height:100px;
    right:-100%;
    top:0;
    background:-sharp99f;
    display:none;
}

< / style >
< ul id= "list" > 

<li class="item">
    <div></div>
</li>
<li class="item">
    <div></div>
</li>
<li class="item">
    <div></div>
</li>


< script src= " https://cdn.bootcss.com/jquer.;></script>
<script>

$('.item').on('mouseover',function(){
    $(this).find('div').css('display','block')
})
$('.item').on('mouseout',function(){
    $(this).find('div').css('display','none')
})

< / script > 

*{
    margin:0;
    padding:0;
}
ul{
    list-style: none;
    position:relative;
    width:500px;
    margin:0 auto;
    height:500px;
}
.item{
    position:relative;
    width:100px;
    height:100px;
    background:-sharpf99;
    border:1px solid -sharpccc;
    cursor:pointer;
    float:left;
}
.hidden{
    position: absolute;
    width:100px;
    height:100px;
    background:-sharp99f;
    display:none;
    top:100%;
    left:0;
}
.bu{
    display:block;
    width:100%;
    height:100%;
}

< / style >
< ul id= "list" > 

<li class="item">
    <a class="bu" href="www.baidu.com"></a>
    <div class="hidden"></div>
</li>
<li class="item">
    <a class="bu"></a>
    <div class="hidden"></div>
</li>
<li class="item">
    <a class="bu"></a>
    <div class="hidden"></div>
</li>


< script src= " https://cdn.bootcss.com/jquer.;></script>
<script>

$('.item').on('mouseover',function(){
    $(this).find('.hidden').css('display','block')
})
$('.item').on('mouseout',function(){
    $(this).find('.hidden').css('display','none')
})

< / script >

Previous: Questions in the php tp framework

Next: A problem of code coverage

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-429b3bf-5a09.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-429b3bf-5a09.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?