<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
</head>
<style>
    .example {
        width: 520px;
        padding: 42px 24px 50px;
        border: 1px solid #f0f0f0;
        margin: 20px auto;
    }
</style>

<body>
    <div class="example">
        <r-radio checked="true">Radio</r-radio>
    </div>

    <div class="exam