Why Aren\'t My Borders Showing on Sticky-Positioned Elements?

Border Styles Not Displaying on Element with Sticky Position

In CSS, the "sticky" position allows an element to remain fixed on the screen even when the surrounding content scrolls. However, when applied to an element with borders, the borders may not appear as expected.

Cause:

This issue arises due to the use of the "border-collapse" property. When set to "collapse," borders between adjacent elements are combined and distributed among those elements. In the case of elements with sticky position, the top border on the sticky element may merge with the border of the containing element (e.g., the table), while the bottom border may merge with the border of the subsequent element.

Solution:

To resolve this problem, you can change the "border-collapse" property from "collapse" to "separate." This will prevent the borders from being combined and ensures that each element has its own distinct border.

Alternatively, you can explicitly define the border on each individual element using CSS rules like:

table thead th {
  border-top: 2px solid;
  border-bottom: 2px solid;
}

This ensures that the border on the sticky table header is applied directly to the cells without being affected by the border-collapse property.

Example:

Implement the following CSS styles to achieve the desired behavior:

table {
  border-collapse: separate;
}

table thead th {
  position: sticky;
  top: 0;
  border-top: 2px solid;
  border-bottom: 2px solid;
}

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