Case File · CSS

Selectors

Selectors

Selectors is a core part of CSS. In this case file you'll learn what it is, why it matters, and how to use it in real code.

Understanding selectors well means you can read other people's CSS code with confidence, and avoid the most common beginner mistakes in this area.

Key points:

  • What selectors means in the context of CSS
  • A minimal example you can run or read in the playground on the right
  • A common mistake to avoid when working with selectors
/* CSS: Selectors */
body {
  font-family: sans-serif;
  background: #0B0F17;
  color: #E5E7EB;
}

.card {
  padding: 1rem;
  border-radius: 0.75rem;
  border: 1px solid #22D3EE55;
}

Tip: Try changing a value in the code on the right and re-running it — small experiments are the fastest way to build real intuition for selectors.

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