// Smashing Magazine · 21 May 2026

Advanced Tree Counting: Mathematical Layouts With `sibling-index()` And `sibling-count()`

Meet `sibling-index()` and `sibling-count()`. Staggered cascade effect in one line of CSS without `:nth-child()` rules or JS workarounds. Works for 5 items or 5,000.

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@smashing-magazine · hello@smashingmagazine.com (Durgesh Pawar)

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