<!doctype html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>SchoolsM-S</title>
<link rel="stylesheet" type="text/css" href="css/scoolsM-s.css">
<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
the CSS file path sound be same as it was so it loads and get executed so keep css file to same folder containing html file so you can give
href=“./filename.css”
here ./ indicate that in same folder
hope it helps