components/web_app_resources/web_app_default_offline.css

/* Copyright 2022 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. */

@media (prefers-color-scheme: light) {
  body {
    background-color: var(--customized-background-color);
  }
  h2 {
    color: var(--theme-color);
  }
 }

@media (prefers-color-scheme: dark) {
  body {
    background-color: var(--dark-mode-background-color);
  }
  h2 {
    color: var(--dark-mode-theme-color);
  }
}

h2 {
  height: 200px;
  left: 50%;
  margin-inline-start: -200px;
  margin-top: -100px;
  position: fixed;
  top: 50%;
  width: 400px;
}