<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>linestring-style-css-filter</title>
    <link rel="stylesheet" type="text/css" href="/ol/ol.css">
    <style>
      html, body {
        margin: 0;
        padding: 0;
        width: 100%;
        height: 100%;
      }
      #map {
        width: 100%;
        height: 100%;
      }
      .bw {
        filter: grayscale(100%);
      }
      .ol-control {
        display: none;
      }
    </style>
  </head>
  <body>
    <div id="map"></div>
    <script src="main.js"></script>
  </body>
</html>
