I need to make it so that in real time, when I type words or letters, they turn green in textarea. But at the same time, mathematical signs or numbers did not change color.

My HTML code:

<textarea id="input" class="syncscroll" oninput="updateCode()" rows="10" placeholder="Enter an expression to start"></textarea>

I’ve tried like this:

function highlightNumbers() {
    const input = document.getElementById('input')
    const htmlContent = input.innerHTML

    // Заменяем числа в тексте на версии с установленным цветом
    const formattedContent = htmlContent.replace(
        /(d+(.d+)?)/g,
        '<span class="number">$1</span>'
    )
    input.innerHTML = formattedContent
}
highlightNumbers()

style.css:

.number {
    color: green;
}