Help create Alternating "Chess-like" Collection-list Grid using Custom CSS

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3

Then since you already have flex applied to each item, simply apply row-reverse:

.w-dyn-item:nth-child(n+5):nth-child(-n+8),
.w-dyn-item:nth-child(n+13):nth-child(-n+16) {
    flex-direction: row-reverse;
}

Screenshot_2018-09-03_120901
Screenshot_2018-09-03_1209011336×800 508 KB

Hint: If you paste custom CSS in an Embed Code component, you can preview the style within the designer itself without having to publish.