chore: Remove unused inappbrowser.css file (#1038)

diff --git a/www/inappbrowser.css b/www/inappbrowser.css
deleted file mode 100644
index 5762c74..0000000
--- a/www/inappbrowser.css
+++ /dev/null
@@ -1,114 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-.inAppBrowserWrap {
-    margin: 0;
-    padding: 0;
-    outline: 0;
-    font-size: 100%;
-    vertical-align: baseline;
-    background: 0 0;
-    position: fixed;
-    top: 0;
-    left: 0;
-    width: 100%;
-    height: 100%;
-    z-index: 9999999;
-    box-sizing: border-box;
-    border: 40px solid #bfbfbf;
-    border: 40px solid rgba(0, 0, 0, 0.25);
-}
-
-.inAppBrowserWrapFullscreen {
-    border: 0;
-}
-
-.inappbrowser-app-bar {
-    height: 70px;
-    background-color: #404040;
-    z-index: 9999999;
-}
-
-.inappbrowser-app-bar-inner {
-    padding-top: 10px;
-    height: 60px;
-    width: 155px;
-    margin: 0 auto;
-    background-color: #404040;
-    z-index: 9999999;
-}
-
-.app-bar-action {
-    width: auto;
-    height: 40px;
-    margin-left: 20px;
-    font-family: "Segoe UI Symbol";
-    float: left;
-    color: white;
-    font-size: 12px;
-    text-transform: lowercase;
-    text-align: center;
-    cursor: default;
-}
-
-.app-bar-action[disabled] {
-    color: gray;
-    /*disable click*/
-    pointer-events: none;
-}
-
-.app-bar-action::before {
-    font-size: 28px;
-    display: block;
-    height: 36px;
-}
-
-/* Back */
-.action-back { 
-    margin-left: 0px;
-}
-
-.action-back::before {
-    content: "\E0BA";
-}
-
-.action-back:not([disabled]):hover::before {
-    content: "\E0B3";
-}
-
-/* Forward */
-.action-forward::before {
-    content: "\E0AC";
-}
-
-.action-forward:not([disabled]):hover::before {
-    content: "\E0AF";
-}
-
-/* Close */
-.action-close::before {
-    content: "\E0C7";
-    /* close icon is larger so we re-size it to fit other icons */
-    font-size: 20px;
-    line-height: 40px;
-}
-
-.action-close:not([disabled]):hover::before {
-    content: "\E0CA";
-}