border-block-start-color

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.

CSS 属性 border-block-start-color 定义了元素的逻辑块首的边框颜色，并根据元素的书写模式、行内方向和文本朝向对应至实体边框颜色。根据 writing-mode、direction 和 text-orientation 所定义的值，此属性对应于 border-top-color、border-right-color、border-bottom-color 或 border-left-color 属性。

尝试一下

border-block-start-color: red;
writing-mode: horizontal-tb;

border-block-start-color: #32a1ce;
writing-mode: vertical-rl;

border-block-start-color: rgb(170, 50, 220, 0.6);
writing-mode: horizontal-tb;

border-block-start-color: hsl(60, 90%, 50%, 0.8);
writing-mode: vertical-lr;

<section class="default-example" id="default-example">
  <div class="transition-all" id="example-element">
    This is a box with a border around it.
  </div>
</section>

#example-element {
  background-color: #eee;
  color: #000;
  border: 0.75em solid;
  padding: 0.75em;
  width: 80%;
  height: 100px;
  unicode-bidi: bidi-override;
}

语法

css
border-block-start-color: blue;
border-block-start-color: #4c5d21;

/* 全局值 */
border-block-start-color: inherit;
border-block-start-color: initial;
border-block-start-color: revert;
border-block-start-color: revert-layer;
border-block-start-color: unset;

与此相关的属性有 border-block-end-color、border-inline-start-color 和 border-inline-end-color，这些属性定义了元素其他边框的颜色。

取值

<'color'>

见 border-color

形式定义

初始值currentcolor
适用元素所有元素
是否是继承属性否
计算值颜色计算值
动画类型按计算值的类型

形式语法

border-block-start-color = 
  <color>     |
  <image-1D>  

<image-1D> = 
  <stripes()>  

<stripes()> = 
  stripes( <color-stripe># )  

<color-stripe> = 
  <color>                            &&
  [ <length-percentage> | <flex> ]?  

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

示例

竖排文本的边框颜色

HTML

html
<div>
  <p class="exampleText">示例文本</p>
</div>

CSS

css
div {
  background-color: yellow;
  width: 120px;
  height: 120px;
}

.exampleText {
  writing-mode: vertical-lr;
  border: 10px solid blue;
  border-block-start-color: red;
}

结果

规范

Specification
CSS Logical Properties and Values Level 1
# border-color

浏览器兼容性

参见