CSS nth-child

:first-child

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:nth-child(2)

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:nth-child(odd)

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:nth-child(even)

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:nth-child(3n)

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:nth-child(n+4)

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:nth-child(-n+4)

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:nth-child(3n+2)

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:nth-child(4n-1)

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:last-child

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