DeflatedPickle/css_switcher.html

## css_switcher.html
<!DOCTYPE html>

<html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Index</title>

        <script rel="script" type="text/javascript" src="switcher.js"></script>
    </head>

    <body>
        <h1>Title</h1>
    </body>
</html>

## linux.css
body {
    background: darkgray;
}

## osx.css
body {
    background: white;
}

## switcher.js
const os = require("os");

function loadCSS(path) {
    if (!document.getElementById) {
        document.write('<link rel="stylesheet" type="text/css" href=path>');
    }
}

switch (os.platform()) {
    case "win32":
        console.log("Windows");
        loadCSS("win32.css");
        break;

    case "darwin":
        console.log("OSX");
        loadCSS("osx.css");
        break;

    case "linux":
        console.log("Linux");
        loadCSS("linux.css");
        break;

    default:
        console.log("Other: %s", os.platform());
}

## win32.css
body {
    background: lightgray;
}
	<!DOCTYPE html>

	<html lang="en">
	<head>
	<meta charset="UTF-8">
	<title>Index</title>

	<script rel="script" type="text/javascript" src="switcher.js"></script>
	</head>

	<body>
	<h1>Title</h1>
	</body>
	</html>
	const os = require("os");

	function loadCSS(path) {
	if (!document.getElementById) {
	document.write('<link rel="stylesheet" type="text/css" href=path>');
	}
	}

	switch (os.platform()) {
	case "win32":
	console.log("Windows");
	loadCSS("win32.css");
	break;

	case "darwin":
	console.log("OSX");
	loadCSS("osx.css");
	break;

	case "linux":
	console.log("Linux");
	loadCSS("linux.css");
	break;

	default:
	console.log("Other: %s", os.platform());
	}