Programonic

The concept

Grid lays out items in rows and columns at once. grid-template-columns defines the columns, with the fr unit sharing the free space. grid-template-areas names regions in a drawing-like way, and grid-area places an element in a region. For a gallery, repeat(auto-fit, minmax(10rem, 1fr)) creates as many columns of at least 10rem as fit, so the grid reflows without media queries. Use Grid for page layout and two-dimensional arrangements, and flexbox for a single row or column of items.

Code example

CSS

.layout {
  display: grid;
  grid-template-columns: 12rem 1fr;
  grid-template-areas:
    "header header"
    "sidebar main"
    "footer footer";
  gap: 1rem;
}
.layout > header { grid-area: header; }
.layout > nav { grid-area: sidebar; }
.layout > main { grid-area: main; }
.layout > footer { grid-area: footer; }

.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr));
  gap: 0.5rem;
}

Preview example Example details

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1.layout {

2 display: grid;

3 grid-template-columns: 12rem 1fr;

4 grid-template-areas:

5 "header header"

6 "sidebar main"

7 "footer footer";

8 gap: 1rem;

9}

10.layout > header { grid-area: header; }

11.layout > nav { grid-area: sidebar; }

12.layout > main { grid-area: main; }

13.layout > footer { grid-area: footer; }

15.gallery {

16 display: grid;

17 grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr));

18 gap: 0.5rem;

19}

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Prepared trace of the published program. Some rows group repeated iterations.
What happens	State after step	Output so far
The element becomes a grid container and its children become grid items.	`—`	—
A fixed 12rem sidebar column and one flexible column that takes the rest.	`—`	—
The header spans both columns. Each quoted string is a row, and each word names a cell.	`—`	—
The second row has the sidebar on the left and the main content on the right.	`—`	—
Place the header element in the area named header.	`—`	—
As many columns as fit, each at least 10rem wide, sharing any extra space equally.	`—`	—

Behind the scenes

How CSS processes this code

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