A gallery with one big tile in HTML & CSS
HTML & CSS interview exercise on Grid, difficulty 2 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
A gallery of square tiles in four equal columns with 8px gaps, where the first tile is a hero that spans two columns and two rows. Every tile stays square (use aspect-ratio), and the hero ends up exactly as wide and as tall as two tiles plus the gap.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.