third_party/WebKit/Source/devtools/front_end/ui/dialog.css

/*
 * Copyright (c) 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.
 */

.widget {
    box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.2), 0 2px 4px rgba(0, 0, 0, 0.2), 0 2px 6px rgba(0, 0, 0, 0.1);
    background: white;
    justify-content: flex-start;
    align-items: stretch;
    display: flex;
}

.dialog-close-button {
    position: absolute;
    right: 9px;
    top: 9px;
    z-index: 1;
}