JSFiddle - React, Tailwind, and code Playground

HTML

<h1>Header</h1>

CSS

h1 {
        overflow: hidden;
        text-align: center;
        position:relative;
    }
    h1:before, h1:after {
        position: absolute;
        top: 51%;
        overflow: hidden;
        width: 40%;
        height: 2px;
        content:'\a0';
        background-color: #e6ebfa;
    }
    h1:before {
        left:0;
    }
    h1:after {
        right:0;
    }