In additiona to below heading or title styles, you can also use heading styles of theXPro base theme.
The-X-Pro - Heading Styles
The-X-Pro - Heading Styles
Underline Style
<h1>Heading with <span class="text-underline">primary underline style</span> and <span class="text-underline-secondary">secondary underline style</span>.</h1>Wavy Underline
<h1>Heading with <span class="text-underline-wavy">wavy underline</span> style.</h1>