After reading the wonderful post by @una, I know what is @property in CSS?

    First of all, it's a CSS Houdini custom property. If you don't know what is CSS Houdini, then read this first.

ok, let's start.

CSS syntax:

// For Chromium 85 and above
  @property --MyColor {
    syntax: '<color>';
    initial-value: red;
    inherits: false;
  }

     If your Chromium browser is from 78 and above and below 85, then you should include some javascript code to make this functionality to work.

Fallback JS code:

CSS.registerProperty({
  name: '--MyColor',
  syntax: '<color>',
  initialValue: 'red',
  inherits: false
});

structure:

• name - name of the property(eg: myColor, columnPercentage, etc...).

• syntax - syntax of the property.
  Allowable values are

  1). length

  2). number

  3). percentage

  4). length-percentage

  5). color

  6). image

  7). url

  8). integer

  9). angle

  10). time

  11). resolution

  12). transform-list

  13). transform-function

  14). custom-ident

• initial-value - Begining value of the property

• inherits - Defines whether inherit the value from the parent or not

    After knowing this thing as a web developer, you might have the following question.

How it defers from normal CSS variables?🤔

    In the CSS variable, we can only give value. But using the @property, we can define the syntax like value should be in color.

So, we can write the code with a more semantical meaning 🔥.

Let's explore this property with the following Example

Note:

    We can able to overwrite the values in the particular block like below.

  @property --Mycolor {
  syntax: '<color>';
  initial-value: red;
  inherits: false;
}
.text {
  --Mycolor: blue;
  color: var(--Mycolor); // blue
}

    If we give invalid value, then it will back off to the initial value. for example, if we give some number value(67) in the color property, then it will back off to the initial value(red).

.text {
  --Mycolor: 67;
  color: var(--Mycolor); // red
}

I hope you enjoyed this post 😍. Thanks for reading.

Source Url: https://web.dev/at-property/