Centrar position absolute
<div class="container">
<h1>item 1</h1>
<small class="absolute">#</small>
</div>
<style>
.container {
position: relative;
display: flex;
justify-content: center;
align-items: center;
}
.absolute {
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%)
}
</style>
Otra forma de hacerlo
<div class="container">
<h1>item 1</h1>
<div class="absolute">
<small>#</small>
</div>
</div>
<style>
.container {
position: relative;
display: flex;
justify-content: center;
align-items: center;
}
.absolute {
position: absolute;
inset: 0;
display: grid;
place-items: center;
}
</style>