A designer notices that stacking two boxes vertically with generous top/bottom margins produces a smaller gap than expected, but placing two boxes side by side with the same margin values produces the full combined gap. What best explains this difference?

A tea shop’s site has a nav link with a light green background and generous padding. A visitor asks whether that green area they see is really part of the link’s clickable box, or just decorative space around it. What’s accurate?

A mobile site’s “Add to Cart” button has very little padding, and users report it’s hard to tap accurately. Without changing the font size or the button’s text, what change would directly address the tap-accuracy complaint?

Nutshell Board Game Cafe’s weekly-events table has one game night that runs the same in three consecutive evening slots, and the developer wants one cell to cover all three rows in that column instead of repeating the text three times. Which attribute fits?

A site’s images occasionally fail to load due to a broken file path, and the developer wants users to at least see something meaningful in that case.

A developer writes `border: #3498db;` alone, expecting a visible blue border to appear.

A site hardcodes `#3498db` directly in a dozen separate CSS rules for buttons, links, and headings, and now the client wants to switch that shade to a different blue everywhere.

A portfolio site stacks a heading with margin-bottom: 40px directly above a paragraph with margin-top: 10px. What’s the resulting visible gap between the heading and the paragraph?

Half Pipe Skate Shop accidentally sets all four offsets — `top`, `right`, `bottom`, and `left` — on the same absolutely positioned element. Which pair wins?

A team wants a modern replacement for their JPEG photos that keeps a similar look but noticeably cuts file size, and would also like the option of transparency for some images.