How to use opacity in css

Usage of opacity in CSS: What is opacity? The opacity attribute controls the opacity of the element, that is, the degree to which the element transmits light. The value range is 0 (completely transparent) to 1 (completely opaque). How to use opacity? The syntax of the opacity attribute is: opacity: value; value can be a number between 0 and 1 or the inherit/initial keyword. Applications of opacity: The opacity attribute is widely used in web design, such as creating transparent backgrounds, fade-in/fade-out effects, overlays, mouseover effects, and image blending.

Usage of opacity in CSS

What is opacity?

The opacity attribute controls the opacity of the element, that is, the degree to which the element transmits light. Its value range is 0 to 1, where:

• 0 means completely transparent (the element is not visible)
• 1 means completely opaque (the element is completely visible)

How to use opacity?

In CSS, use the opacity attribute to set the opacity of an element. The syntax is as follows:

opacity: value;

Among them, value can be a number between 0 and 1, or you can use The following keywords:

• inherit: Inherit the opacity of the parent element
• initial: Use the browser's default opacity

opacity Application

The opacity attribute is widely used in web design, for example:

• Create a transparent background:Set the opacity of the background element to 0, you can create a transparent background effect.
• Fade in/fade out effect: By gradually changing the opacity value, you can create a fade in or fade out animation effect.
• Overlay: Use the opacity attribute to create a translucent overlay to block part of the content or provide additional information.
• Mouse hover effect: When the mouse hovers over an element, you can change the display effect of the element by changing the opacity value.
• Image Blending: You can create an image blending effect by overlaying the opacity of multiple images.

Example:

To set the opacity of an element to 50%, you would write:

opacity: 0.5;

To create a fade-in Effect that gradually increases the opacity of an element over a period of time, for example:

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

element {
  animation: fadeIn 1s;
}

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