When I look up css properties in MDN's specifications section, there are some properties in it and it seems unfamiliar to me. So I try to find out some of them today.

The follow list try to give one word to specify the meaning of them.

  • Initial value: Specify the CSS property's default value;
  • Applies to: Specify which elements to apply to;
  • Inherited: Specify the CSS property is inherited or non-inherited;
  • Media: Specify how a document is to be presented on different media;
  • Computed value: The CSS property that is transferred from parent to child;
  • Animation type
  • Canonical order: Some CSS properties(font、background...) have their own CSS property value order.

And this article is to discuss the topic about the knowledge of inherited and non-inherited.

Initial value between inherited and non-inherited

The initial value of a CSS property is its default value.

The Initial value has two different behavior between inherited properties and non-inherited properties.

For inherited properties, the initial value is used on the root element only.

<span style="color: red">
  hello, <em>CSS</em>
</span>

The result is the color of both span and em element are red. Because the color is an inherited property, the element will get the color property from the parent recursively until to document.

For non-inherited properties, the initial value is used on every element. When no value for a non-inherited property has been specified on an element, the element gets the initial value directly.

<span style="border: 1px solid black">
  hello, <em>CSS</em>
</span>

The result is the border is only effected on span element, not em. Because the border is a non-inherited property, and there is no border property specified on the em, so the em get the border's initial value none.

It mentioned much times about inherited value and non-inherited value above, and now we sort out css properties.

Inherited Type

I've collected some inherited types in css, they are listed as follow:

  • Font Type: font-style、font-variant、font-weight、font-stretch、font-size、font-family、color、line-height;
  • Space Type: letter-spacing、word-spacing、white-space;
  • Letter Type: text-align、text-indent、text-shadow、text-transform;
  • List Type: list-style、list-style-type、list-style-position;
  • Others: visibility、cursor;

Non-Inherited Type

In the opposite of inherited type, the non-inherited types are listed as follow:

  • Layout Type: float、position、left、right、top、bottom、z-index、display
  • Box Type: width、max-width、min-width、height、max-height、min-height、margin、padding、border;
  • Background Type: background-size、background-image、background-clip、background-color、background-origin、background-position、background-repeat;
  • Others: overflow、text-overflow、vertical-align;

Recap

These section introduces the inherited concept in CSS, and distinguish some inherited type and some non-inherited type from css properties. Hope it's helpful for you.


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