What is the difference between margin and padding?

Padding is the space inside an element, between its content and its border. Margin is the space outside the border, separating the element from its neighbours.

When should I use flexbox versus grid?

Flexbox is best for laying out items in a single direction, a row or a column, and distributing space along that axis. CSS grid is best for two-dimensional layouts where you control both rows and columns at once.

Is anything I search sent to a server?

No. The full property list and the search both run entirely in your browser — nothing you type is uploaded anywhere.

CSS Properties Reference

Common CSS properties grouped by purpose and searchable.

CSS properties — searchable reference

A grouped, searchable list of the CSS properties you use most: the box model (margin, padding, border), layout (display, position), flexbox and grid, typography (font-size, line-height), colour and transitions — each with a plain-English description.

Search by property name or description to find what you need instantly. Everything runs in your browser; nothing is uploaded.