<!-- Licensed under a BSD license. See license.html for license -->
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<title>Environment Mapping Diagram</title>
<style>
:root {
  color-scheme: light dark;
}
html, body {
  margin: 0;
  height: 100%;
}
canvas {
  width: 100%;
  height: 100%;
  display: block;
  cursor: crosshair;
}
@media (prefers-color-scheme: dark) {
  canvas {
    background: #444;
  }
}
</style>
<