JSFiddle - React, Tailwind, and code Playground

HTML

<div id="control">
    <input type="radio" onclick="alert('ok');return false;" value="送出"/>
</div>

<div id="block">
    <div id="content">
        <h3>優先順序較高的圖層</h3>
    </div>
</div>

CSS

#control
{
    position:fixed;
    z-index: 1000;
}
#block {
    position:static;
    z-index:auto;
    display:inline-block;
    opacity:.80;
    pointer-events: none;
}

#content {
    margin:auto;
    width:300px;
    background-color:#7db0f4;
    border:1px solid #CCC;
    text-align:center;
}