4.2.3 #Style.border.widths Border widths

Toggle example guides Toggle HTML markup

Various border widths are available by level number: top, bottom, left, right,

Browser support: IE3+, Safari1+, Firefox1+, Chrome10+

Default styling
Text
.sb-border-width-l
large
Text
.sb-border-width-xl
extra large
Text
Markup 
<span class="sb-padding-xs sb-border-black [modifier class]">Text</span>
Source: trumps/_border.scss, line 74