index.css

/* Copyright 2015 The Chromium Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file. */

body {
  background-color: rgb(82, 86, 89);
  font-family: 'Roboto', 'Noto', sans-serif;
  margin: 0;
}

viewer-page-indicator {
  visibility: hidden;
  z-index: 2;
}

viewer-pdf-toolbar {
  position: fixed;
  width: 100%;
  z-index: 4;
}

#plugin {
  height: 100%;
  position: fixed;
  width: 100%;
  z-index: 1;
}

#sizer {
  position: absolute;
  z-index: 0;
}

@media(max-height: 250px) {
  viewer-pdf-toolbar {
    display: none;
  }
}

@media(max-height: 200px) {
  viewer-zoom-toolbar {
    display: none;
  }
}

@media(max-width: 300px) {
  viewer-zoom-toolbar {
    display: none;
  }
}