<!DOCTYPE html>
<html>
<head>
<style>
p.ex1 {
border: 1px solid yellow;
outline-style: solid;
outline-color: invert;
}
</style>
</head>
<body>
<h1>使用 outline-color:invert</h1>
<p class="ex1">invert 实线轮廓</p>
</body>
</html>