CSS
The language for styling and laying out HTML pages.
1. Introduction to CSS
What CSS is, how a rule is structured, and the three ways to attach it — with why one of them is almost always the right choice.
2. Selectors
Targeting elements by tag, class, id, or combinations of these — and how CSS decides which rule wins when two rules conflict.
3. Colors & Backgrounds
Setting text and background color by name, hex, or rgb — and what that fourth rgba number actually controls.
4. The Box Model
Content, padding, border, and margin — the four layers every element is built from, and the one setting that changes how they're measured.
5. Text & Fonts
font-family, font-size, font-weight, and text-align — and why a font-family list always needs a fallback.
6. Flexbox
Laying out a row (or column) of items with display: flex — the single most useful layout tool for everyday UI work.
7. Grid
Two-dimensional layouts with display: grid — when to reach for it instead of flexbox.
8. Positioning
static, relative, absolute, and fixed positioning — and the parent/child relationship that makes absolute positioning predictable instead of confusing.
9. Responsive Design (Media Queries)
Changing styles based on screen width with @media — and why the mobile-first approach beats designing desktop-first.
10. Transitions & Hover Effects
Animating property changes smoothly with the transition property — and why it needs to be paired with :hover to actually be noticed.