<!doctype html>
<html>
<head>
<meta charset="utf-8">
<style type="text/css">
.selected {
border-radius: 3px;
-webkit-box-decoration-break: clone;
}
::selection {
background: rgba(0, 0, 0, .25);
}
</style>
<script>
function styliString(color) {
const selection = getSelection();
const range = selection.getRangeAt(0);
const selectionContents = range.extractContents();
const span = document.createElement("span");
for(const oldSpan of selectionContents.querySelectorAll(".selected")) {
for(const childNode of [...oldSpan.childNodes])
oldSpan.parentNode.insertBefore(childNode, oldSpan);
oldSpan.remove();
}
selectionContents.normalize();
span.classList.add("selected");
span.style.backgroundColor = color;
span.appendChild(selectionContents);
range.insertNode(span);
}
document.addEventListener("click", ({ target }) => {
if(target.classList.contains("color")) {
styliString(target.dataset.color || target.textContent);
}
});
</script>
</head>
<body>
<button class="color" data-color="#f06">Pink</button>
<button class="color">Gold</button>
<button class="color">Yellowgreen</button>
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</body>
</html>
