We suggest to use classes also for default elements like headings. Link will come soon to provide reasoning behind.
<h3 class="lbh-u-h3">Medium 20px</h3>
.lbh-u-h1,
.lbh-u-h2,
.lbh-u-h3,
.lbh-u-h4 {
font-weight: 700;
}
.lbh-u-h1 {
font-size: var(--font-size-heading-xlarge);
}
.lbh-u-h2 {
font-size: var(--font-size-heading-large);
}
.lbh-u-h3 {
font-size: var(--font-size-heading-medium);
}
.lbh-u-h4 {
font-size: var(--font-size-heading-small);
}