Broken header widget

I have a widget set for my header with the styles set in the style sheet.

This is the code for my header:
<h4>Phone Us Now On</h4>
<h5>01202 048696 | 0845 450 7990</h5>
<h4>[email protected] </h4>

And this is what I have as h4

#text-5 h4 {
color: #b9d40f;
font-size: 36px;
text-align: center;
}

My website is https://www.thefriendlyaccountants.co.uk

…and it is no longer formatting my header correctly – but I don’t know why!

Is anyone able to help me with what I’ve done wrong please?

Thank you in advance.