/* starting with an element selector */
h1
{
  background-color: #fff;
}
h1#foo
{
  font-size: 50pt;
}
h1.bar
{
  border: none;
}
h1#foo.exp
{
  position: absolute;
}
h1#foo.exp.bar
{
  position: relative;
}

/* start with an id */
#someid
{
  color: red;
}
#bar.class
{
  right: 0px;
}
#bar.class.ack
{
  right: 10px;
}

/* start with a class */
.someclass
{
  color: Red;
}
.oneclass.twoclass
{
  color: #fff;
}