CSS Box Model and Spacing
Every element is a box made from content, padding, border and margin.
*,
*::before,
*::after {
box-sizing: border-box;
}
.card {
max-width: 42rem;
padding: 1rem;
border: 1px solid #cbd5e1;
margin-block: 1rem;
}
With border-box, declared width includes padding and border.
Use padding inside a component and margin between components. Prefer relative units such as rem for scalable spacing.
Avoid fixed layouts
Large fixed widths can overflow small screens. Combine width: 100% with a suitable max-width.
Check
- Global border-box rule is present.
- Spacing has a consistent scale.
- Content does not touch borders.
- Page has no horizontal scrolling at narrow widths.