从font的color属性继承边框颜色是正常的吗？我很惊讶地发现：
div
{
border: 4px solid;
color: red;
height: 100px;
width: 100px;
}
<div></div>
给了我一个带红色边框的div。通常不指定颜色将默认为黑色。这个奇怪的遗产是什么？
解决方法
根据相关
Backgrounds and Borders Module spec的
section 4.1，初始边界颜色值为
currentColor：
07003
CSS1 and CSS2 defined the initial value of the
border-colorproperty to be the value of thecolorproperty but did not define a corresponding keyword. This omission was recognized by SVG,and thus SVG 1.0 introduced thecurrentColorvalue for thefill,stroke,stop-color,flood-color,andlighting-colorproperties.CSS3 extends the color value to include the
currentColorkeyword to allow its use with all properties that accept a <color> value. This simplifies the definition of those properties in CSS3.
换句话说，在您的情况下，该值被视为以下内容：
border: 4px solid currentColor;
因此，您还可以将currentColor值用于诸如background-color属性之类的内容。例如：
div {
color: red;
width: 100px;
height: 100px;
border: 4px solid;
background-color: currentColor;
}
<div></div>
很有趣的事实，如果你改变字体颜色(例如：悬停)，边框颜色会随之改变！ It also works well with transitions!
