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← All coursesModern CSS: Features That Replace JavaScript5 levels · 24 lessons

Animate height to auto without a guessed max-height~11 min
Animate in and out of display: none without a timer~9 min
Put a popover above every z-index without a portal~10 min
Anchor a tooltip to its button without a positioning library~9 min
Your ResizeObserver measures a width the browser already has~8 min
Scroll-snap carousels, and the CSS arrows and dots only Chromium ships~9 min
CSS that replaces JavaScript · Review~5 min

A working subgrid reports no track sizes~9 min
What `container-type` charges~8 min
What :has() weighs~7 min
Asking an element whether it is stuck~7 min
startViewTransition captures the old page before your callback runs~8 min
Styling a component from its context · Review~5 min

The seat that will not change colour~8 min
& resolves through an implicit :is()~7 min
Proximity is not encapsulation~7 min
Layers, nesting and scope in the cascade · Review~5 min

What a group weighs~8 min
Physical and logical are separate properties~6 min
Specificity arithmetic · Review~5 min

Invalid at computed-value time is not initial~7 min
Why HSL lightness does not match how light a colour looks~7 min
style(--x) means "differs from the initial value"~7 min
Values that compute · Review~5 min

Course

Modern CSS: Features That Replace JavaScript

Four jobs you still do in JavaScript that the browser now does for you.

Start free: Animate height to auto without a guessed max-height

The levels

Level I · 7 lessonsCSS that replaces JavaScript