Just make the span valid as a block element.
h1 span{display: block; background:#000; color:#fff; padding:5px 10px;}
to change . JavaScript solution. Divide the contents of the range into several intervals.
var span = document.getElementById("txt"); var newSpans = "<span>" + span.innerHTML.replace(/<br\s*[\/]?>/g, "</span><br /><span>") + "</span>"; span.parentNode.innerHTML = newSpans;
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