:first-child Selector

Соответствует элементам, которые идут первыми в своих непосредственных предках.

:first-of-type Selector

Фильтрует набор выбранных элементов, оставляя только те элементы, которые первыми будут встречены в своих родителях.

:nth-last-child() Selector

Selects all elements that are the nth-child of their parent, counting from the last element to the first.

:nth-last-of-type() Selector

Selects all the elements that are the nth-child of their parent in relation to siblings with the same element name, counting from the last element to the first.

:nth-of-type() Selector

Selects all elements that are the nth child of their parent in relation to siblings with the same element name.