UL kaskadierung in smartmenu

[selfman]

Ich lese in smartmenu.org's style.css

.sm-simple > li:first-child {
  border-top: 0;
}

.sm-simple ul {
  background: rgba(179, 179, 179, 0.1);
}

.sm-simple ul a, .sm-simple ul a:hover, .sm-simple ul a:focus, .sm-simple ul a:active {
  font-size: 14px;
  border-left: 8px solid transparent;
}

.sm-simple ul ul a,
.sm-simple ul ul a:hover,
.sm-simple ul ul a:focus,
.sm-simple ul ul a:active {
  border-left: 16px solid transparent;
}

.sm-simple ul ul ul a,
.sm-simple ul ul ul a:hover,
.sm-simple ul ul ul a:focus,
.sm-simple ul ul ul a:active {
  border-left: 24px solid transparent;
}

.sm-simple ul ul ul ul a,
.sm-simple ul ul ul ul a:hover,
.sm-simple ul ul ul ul a:focus,
.sm-simple ul ul ul ul a:active {
  border-left: 32px solid transparent;
}

.sm-simple ul ul ul ul ul a,
.sm-simple ul ul ul ul ul a:hover,
.sm-simple ul ul ul ul ul a:focus,
.sm-simple ul ul ul ul ul a:active {
  border-left: 40px solid transparent;
}

Kann man uls einfach kaskadieren und so verschachtelte uls stylen ? Wo ist das dokumentiert ?