Smooth Animation for Bootstrap 4 collapse - html

Question

I got what I'm looking for but the animation effect isn't smooth as it should. I understand that the animation would be better if I don't have padding but I need padding to get the design. How do I solve this problem?
JSFiddle DEMO
HTML:
<div class="container">
<div class="row">
<div class="col-sm-12">
<div class="block">
<label class="checkbox"> This is my checkbox
<input type="checkbox" data-toggle="collapse" data-target="#collapseExample">
</label>
<div class="collapse" id="collapseExample">
<div class="row">
<div class="col-12">
<div class="form-group">
<input type="number" class="form-control" placeholder="option one">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option two">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option three">
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
CSS:
.block {
margin-top: 30px;
}
.collapse {
background-color: #eee;
padding: 30px 15px;
}
This is base on Bootstrap 4, the latest version.

Answer 1

When you set .collapse it first apply the bootstrap style of .collapse and after yours because that there is delay...
Use the id #collapseExample to style:
.block {
margin-top: 30px;
}
#collapseExample{
background-color: #eee;
padding: 30px 15px;
}
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"></script>
<div class="container">
<div class="row">
<div class="col-sm-12">
<div class="block">
<label class="checkbox"> This is my checkbox
<input type="checkbox" data-toggle="collapse" data-target="#collapseExample">
</label>
<div class="collapse" id="collapseExample">
<div class="row">
<div class="col-12">
<div class="form-group">
<input type="number" class="form-control" placeholder="option one">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option two">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option three">
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
EDIT to your comment!
There's a "drag" when it closes.
Use jquery onclick the checkbox and apply padding as below:
fiddle here
$('.checkbox').on('click', function(){
if($('.collapse.show').length>0)
$('.collapse').css('padding','0');
else
$('.collapse').css('padding','30px 15px');
});
.block {
margin-top: 30px;
}
#collapseExample{
background-color: #eee;
}
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"></script>
<div class="container">
<div class="row">
<div class="col-sm-12">
<div class="block">
<label class="checkbox"> This is my checkbox
<input type="checkbox" data-toggle="collapse" data-target="#collapseExample">
</label>
<div class="collapse" id="collapseExample">
<div class="row">
<div class="col-12">
<div class="form-group">
<input type="number" class="form-control" placeholder="option one">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option two">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option three">
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>

Answer 2

I got it resolved. It's because I added the padding in parent div.
.block {
margin-top: 30px;
}
.block__collapse {
background-color: #eee;
padding: 30px 15px;
}
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"></script>
<div class="container">
<div class="row">
<div class="col-sm-12">
<div class="block">
<label class="checkbox"> This is my checkbox
<input type="checkbox" data-toggle="collapse" data-target="#collapseExample">
</label>
<div class="collapse" id="collapseExample">
<div class="block__collapse">
<div class="row">
<div class="col-12">
<div class="form-group">
<input type="number" class="form-control" placeholder="option one">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option two">
</div>
<div class="form-group">
<input type="number" class="form-control" placeholder="option three">
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>