console 命令行工具 X clear
console
<!DOCType html>
<html>
<head>
    <meta charset="utf-8">
    <style>
        .hr {
            width: 300px;
            background-color: #000;
        }
        .hr.half-px {
            height: 0.5px;
        }
        .hr.one-px {
           height: 1px;
        }
        .hr.scale-half {
           height: 1px;
           transform: scaleY(0.5);
           transform-origin: 50% 100%;
}
    </style>
</head>
<body>
    <p>0.5px</p>
    <div class="hr half-px"></div>
    <p>1px</p>
    <div class="hr one-px"></div>
    <p>1px + scaleY(0.5)</p>
    <div class="hr scale-half"></div>
</body>
</html>