How can I edit Color Confirmation Addon to make tooltips into squircles?

Anki Add-ons
2

I’ve tried adding the following modifications, but they didn’t work:

# apply width and height
styleString1 = "height:100%; height: 100%; background: red; border-radius: 10px;"
styleString2 = "padding: 8px 13px; text-align: center; border-radius: 10px;"

lab = CustomLabel("""\
<table cellpadding=0 padding=0px style="height:100%; height: 100%; border-radius: 10px;">
<tr>
<td style="padding: 8px 13px; text-align: center; border-radius: 10px;">"""+msg+"""</td>
</tr>
</table>""", aw)