Techniques for CSS Overlays

Jan 19, 2025

CSS Overlay Techniques

Introduction

  • Common issue: Text readability on background images.
  • Solution: Overlay color or effect.

Traditional Method

  • Use of pseudo-elements to create overlays.
  • Steps:
    • Add pseudo-element with CSS.
    • Use position: relative on the hero to avoid full viewport coverage.
    • Adjust z-index for stacking context.
    • This method adds extra CSS code.

Improved Method with Overlay Class

  • Create an overlay class for better separation of concerns.
  • Benefits:
    • Reusable across multiple background images.

Implementation Steps

  1. Define a border image with a linear gradient.
  2. Example gradient: border-image-source: linear-gradient(red, blue);
  3. Border images need:
    • border-style: solid;
    • Introduce border-image-slice to dictate how the image is filled.
    • Example: border-image-slice: 1;
  4. To fill the empty space, add the fill keyword:
    • Result: The image fills the entire element, not just the border.

Opacity Adjustments

  • Adjust the gradient colors to be semi-transparent (e.g., 0.3 opacity for both colors).
  • Importance: Ensures text remains readable.

Simplifying the CSS Code

  • Remove unnecessary border width and style properties.
  • Combine properties using border-image shorthand.
  • Example: border-image: linear-gradient(..., ...); fill;

Final Adjustments

  • Experiment with opacity for better contrast.
  • Example adjustments: Increase opacity to 0.6 for better readability.

Learning Resources

  • Mentioned a CSS course "CSS Demystified" for those wanting to enhance their CSS skills.

Acknowledgements

  • Thanked patrons for support.
  • Encouraged listeners to improve their web design skills.