Hallo Martin, hi Mike!
Try
background-color:transparent;
.
How is this one?
<body style="[code lang=css]background-color:#ff0000
~~~">
<a href="#" style="`color:black`{:.language-css}" onmouseover="`document.body.style.backgroundColor=''`{:.language-javascript}">don't touch me, else I will set backgroundcolor to bladhiblahdiblah!</a>
</body>[/code]
Regards, Gernot