mask-border-width CSS property sets the width of an element's mask border .

句法

/* Keyword value */
mask-border-width: auto;
/* <length> value */
mask-border-width: 1rem;
/* <percentage> value */
mask-border-width: 25%;
/* <number> value */
mask-border-width: 3;
/* vertical | horizontal */
mask-border-width: 2em 3em;
/* top | horizontal | bottom */
mask-border-width: 5% 15% 10%;
/* top | right | bottom | left */
mask-border-width: 5% 2em 10% auto;
/* Global values */
mask-border-width: inherit;
mask-border-width: initial;
mask-border-width: unset;
					

mask-border-width property may be specified using one, two, three, or four values chosen from the list of values below.

  • When one value is specified, it applies the same width to all four sides .
  • When two values are specified, the first width applies to the top and bottom , the second to the left and right .
  • When three values are specified, the first width applies to the top , the second to the left and right , the third to the bottom .
  • When four values are specified, the widths apply to the top , right , bottom ,和 left in that order (clockwise).

<length-percentage>
The width of the mask border, specified as a <length> <percentage> . Percentages are relative to the width of the border area for horizontal offsets and the height of the border area for vertical offsets. Must not be negative.
<number>
The width of the mask border, specified as a multiple of the corresponding border-width . Must not be negative.
auto
The width of the mask border is made equal to the intrinsic width or height (whichever is applicable) of the corresponding mask-border-slice . If the image does not have the required intrinsic dimension, the corresponding border-width is used instead.

形式定义

初始值 auto
适用于 all elements; In SVG, it applies to container elements excluding the defs element and all graphics elements
继承 no
百分比 relative to width/height of the mask border image area
计算值 as specified, but with relative lengths converted into absolute lengths
动画类型 discrete

形式句法

[ <length-percentage> | <number> | auto ]{1,4}

where
<length-percentage> = <length> | <percentage>

范例

基本用法

This property doesn't appear to be supported anywhere yet. When it eventually starts to be supported, it will serve to define the width of the border mask — setting this to a different value to mask-border-slice will cause the slices to be scaled to fit the border mask.

mask-border-width: 30 fill;
					

Chromium-based browsers support an outdated version of this property — mask-box-image-width — with a prefix:

-webkit-mask-box-image-width: 20px;
					

注意 : The mask-border page features a working example (using the out-of-date prefixed border mask properties supported in Chromium), so you can get an idea of the effect.

规范

规范 状态 注释
CSS Masking Module Level 1
The definition of 'mask-border-width' in that specification.
候选推荐 初始定义

浏览器兼容性

TBD

元数据

  • 最后修改: