But beware: The opacity property not only makes the styled element transparent — it also makes its child elements transparent. In other words, if I style a div that contains text with the opacity property, then both the div and the text in the div will be transparent. That can make the text really difficult to read, as in the example below.
The first three numbers represent the intensity of the respective primary color r ed, b lue, g reen as an integer between 0 and The fourth value — ranging from 0 to 1 — sets the transparency of the color. Setting the opacity of text in CSS is nearly identical to setting the opacity of the background of an element.
You can set the opacity of an entire element — the background, text within the element, the border, and everything else — using the opacity property.
When adjusting the opacity of text, make sure you maintain a color contrast ratio so that all users — including those with disabilities related to vision — can see and read the text. Large text is defined as Large text is defined as at least 14 point bolded text or 18 point text.
Setting the opacity of a border in CSS is like setting the opacity of text. You can set the opacity of an image in CSS as well. The opacity property is frequently used with the :hover selector to style an image. That way, the opacity of the image will change only when a user hovers over it. You have two options. You can have the image become transparent when the user hovers over it and then become opaque when their mouse moves away.
Or, you can set it so the image is somewhat transparent and then becomes opaque when the user hovers over it. You can also combine the opacity property with the animation or transition property to create a fade-in image transition in CSS. In CSS, you can create a color gradient that shows one color gradually changing into another in a certain direction like top to bottom, left to right, or diagonally.
In the following example opacity is changed on hover, so the striped background image on the parent element shows through the image. Value Meaning 0 The element is fully transparent that is, invisible. For example: background : rgba 0 , 0 , 0 , 0. Syntax: Attention reader! The alpha parameter is a number between 0.
CSS is the foundation of webpages, is used for webpage development by styling websites and web apps. Skip to content. Change Language. Related Articles. Table of Contents. The CSS for this is opacity:1;. When using the opacity property to add transparency to the background of an element, all of its child elements inherit the same transparency. This can make the text inside a fully transparent element hard to read:. If you do not want to apply opacity to child elements, like in our example above, use RGBA color values.
The following example sets the opacity for the background color and not the text:. An RGBA color value is specified with: rgba red, green, blue, alpha.
The alpha parameter is a number between 0.
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