Questions
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1How can you centre text vertically and horizontally inside a box?
2What is the use of the white-space property?
3How can you truncate text with an ellipsis (...) in CSS?
4How do you wrap or prevent wrapping of text in a container?
5How do you make text responsive across different screen sizes?
6How do you justify text using CSS?
7What does text-shadow do? Give an example.
8How can you apply multiple shadows to text?
9How do you apply gradients to text in CSS?
10How do you control text overflow in a fixed-width container?
11What is the difference between em, rem, and px when styling text?
12How does font-weight differ from <b> tag in semantic meaning?
13How does accessibility relate to text formatting in HTML?
14What’s the difference between semantic and non-semantic text formatting tags?
15How can you ensure consistent text appearance across different browsers?
16What is the difference between font-style, font-variant, and font-weight?
17What is the role of @font-face in web typography?
18How can you import custom fonts in CSS?
19What’s the impact of using web fonts on performance?
20How can you optimise text rendering for readability?
21How do you make text appear vertically (top-to-bottom) using CSS?
22How do you style only the first letter or first line of a paragraph?
23How do you create a drop cap effect?
24How can you highlight a selected text range dynamically?
25How do you make text glow or have a neon effect using CSS?
26What CSS properties can you use for text animations?
27How can you apply a gradient background only to the text and not the entire element?
28How can you apply different styles to different words in the same line?
29How do you prevent text selection on a webpage?
30How do you implement responsive typography (fluid text size)?
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What is the difference between em, rem, and px when styling text?

Understanding em, rem, and px in CSS

CSS provides several units for sizing text. Choosing the right unit affects scalability, accessibility, and responsiveness.

Unit Differences
  1. 1

    px (pixels) – Absolute unit. Defines a fixed size regardless of parent or root element. Not responsive but precise for exact control.

  2. 2

    em – Relative to the font-size of the parent element. Multiplicative; nesting can compound sizes.

  3. 3

    rem – Relative to the font-size of the root (<html>) element. Predictable scaling independent of parent elements.

Example: Using em, rem, and px

In this example, .container sets the text size relative to the root element using rem. .text-em sizes text relative to the parent (.container), and .text-px is fixed.

Key Takeaways
  1. 1

    px is fixed; use for precise control but less flexible for responsive design.

  2. 2

    em is relative to the parent; useful for scaling components but can compound unintentionally.

  3. 3

    rem is relative to the root; ideal for consistent, scalable typography across a site.

  4. 4

    Combine relative units with media queries or clamp() for responsive, accessible text.