position:absolute
个就行了
.container {
width: 400px;
padding: 5px;
border: 1px solid;
text-align: center; /* center the text */
/* to illustrate the center */
background:linear-gradient(red 0 0) 50%/2px 100% no-repeat;
}
.label {
position: absolute; /* out of the flow but don't define any position */
}
.title {
margin-inline: 5px; /* control the gap */
}
<div class="container">
<span class="title">Header</span>
<span class="label">today</span>
</div>