<!DOCTYPE html>
<html>
<style>
    body { margin: 0; }

    #button {
        display: inline-block;
        width: 100px;
        height: 100px;
        background-color: green;
        cursor: pointer;
        border-radius: 10px;
    }
</style>
<body>
<div id="button" onclick="click()"></div>

<pre id="results"></pre>
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window.onload = function () {
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</body>
</html>