I'm currently testing to modify .htmls with Powershell. Which works fine. Only problem I'm having (for now) is, that the CSS appears to be empty after loaded.
Firefox shows, that the .css is loaded but in Firebug it says (roughly translated) "No style rules where defined. You can create rules"
My head:
<head>
<title>Phantom by HTML5 UP</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<link rel="stylesheet" href="assets/css/main.css" type="text/css">
</head>
I'm currently working on a Xampp.
Edit1: I tried with Firefox and Chrome
Edit2: main.css does contain code and I tried with another .css