Opacity

Opacity sets the transparency of an element, including background, text and border.
It accepts values from 0.0 fully transparent to 1.0 fully opaque.
A similar effect that only applies to color and background-color can be achieved using the alpha transparency of rgba color eg background-color:rgba(0, 255, 0, 0.5);
Versions of IE 8 and earlier needed the proprietary filter property eg filter:alpha(opacity=40);

background-origin

Specifies where the background image is attached in the box.

  • content-box is the area inside any padding or border.
  • padding-box is from the outside edge of the padding.
  • border-box is from the outside edge of the border and will sit on top of and cover the background.

When background-attachment is set to fixed this property has no effect.

See also:

Debugging CSS problems

Validate
Use a valid doctype and validate your markup and styles.
This will help you find out if something as simple as a typo or an unclosed element is causing the problem.

Test in other browsers
Browsers have different base styles and varying support for CSS properties. Knowing in which browsers the problem occurs, make it easier to find a solution. Your problem may be a browser not implementing a CSS property.

Inspect

What CSS preprocessor do you use?

Sass
27% (4 votes)
Less
13% (2 votes)
Other
0% (0 votes)
None
60% (9 votes)
Total votes: 15

Happy Birthday to us

I can't believe the forum is now 9 years old. That must be like 100 in web years. The site is actually a few months older then the forum and started as way to display a tool I called the CSS Creator which allowed you to make style changes to live sites. Here's a link to the wayback machine from December 2002, and the CSS Generator as it is today.

Thanks to all who help make this a great place to solve CSS issues and browser issues.

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