<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width">
<style>
.container {
    position: relative;
    width: 500px;
    height: 200px;
    margin: 20px;
    border: 1px solid black;
}

.editable {
    -webkit-user-modify: read-write;
    background-color: aquamarine;
    border: 2px solid green;
}

.overlapper {
    position: absolute;
    top: 0;
    height: 100%;
    width: 50%;
    background-color: rgba(255, 255, 255, 0.75);
    border: 1px solid black;
    z-index: 1;
    box-shadow: 0 0 10px black;
}

.tap-point {
    position: absolute;
    height: 10px;
    width: 10px;
    border-radius: 50%;
    background-color: red;
    z-index: 1;
}
</style>
</head>
<body>
<h2>Non-composited overlap</h2>
<div class="container">
    <div class="editable" style="margin: 10px; height: 100px"></div>
    <div class="overlapper"></div>
</div>

<h2>Composited overlap</h2>
<div class="container">
    <div class="editable" style="margin: 10px; height: 100px"></div>
    <div class="overlapper" style="transform: translateZ(0)"></div>
</div>

<div class="tap-point" style="top: 150px; left: 270px"></div>
<div class="tap-point" style="top: 400px; left: 270px"></div>
<p>Tap near the red dots</p>
</body>
</html>