CSS Property:
text-decoration-style:

Note: The text-decoration-style property is not supported in any of the major browsers.

Note: Firefox supports an alternative, the -moz-text-decoration-style property.

Result:
Hello world!
CSS Code:
#myDIV {
text-decoration: underline;
text-decoration-style: solid;
}
Click the property values above to see the result
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