<dl class="child">
	<dt>dt</dt>
	<dd>1番目のdd</dd>
	<dd>2番目のdd</dd>
	<dd>3番目のdd</dd>
</dl>

<dl class="of-type">
	<dt>dt</dt>
	<dd>1番目のdd</dd>
	<dd>2番目のdd</dd>
	<dd>3番目のdd</dd>
</dl>
dt {
  font-weight: bold;
}

dd {
  margin: 0;
}

.child *:first-child {
	&:after {
    color: red;
		content: '←これは:first-childです';
	}
}

.of-type {
  *:first-of-type:after {
    color: green;
  }
  
  dt:first-of-type:after {
    content: '←これはdt:first-of-typeです';
  }
  
  dd:first-of-type:after {
    content: '←これはdd:first-of-typeです';
  }
}
View Compiled
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