[DevTools] Improve Device Mode icons.

third_party/WebKit/Source/devtools/front_end/emulation/deviceModeView.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.
  */
 
 :host {
     overflow: hidden;
     align-items: stretch;
     flex: auto;
     background-color: #fcfcfc;
 }
 
 .device-mode-toolbar {
     flex: none;
     background-color: #f3f3f3;
     border-bottom: 1px solid #ccc;
     display: flex;
     flex-direction: row;
     align-items: stretch;
     padding: 0 4px;
 }
 
-.device-mode-toolbar > .toolbar {
+.device-mode-toolbar .toolbar {
     padding: 0;
     overflow: hidden;
+    flex: auto;
+}
+
+.device-mode-toolbar-left {
+    flex: 0 1000 115px;
+    min-width: 93px;
+}
+
+.device-mode-toolbar-right {
+    flex: 0 1000 115px;
+    min-width: 40px;
+    display: flex;
 }
 
 .device-mode-toolbar-middle-container {
-    flex: auto;
+    flex: 1 1 120px;
     position: relative;
 }
 
 .device-mode-toolbar-middle {
     display: flex;
     justify-content: flex-start;
     overflow: hidden;
 }
 
 .device-mode-toolbar-middle .toolbar {
-    flex-shrink: 1;
+    flex: 0 1 auto;
 }
 
 .device-mode-toolbar-spacer {
     flex: auto;
 }
 
 .device-mode-content-clip {
     overflow: hidden;
     flex: auto;
 }
 
 .device-mode-media-container {
     flex: none;
     overflow: hidden;
+    box-shadow: inset 0 -1px #ccc;
 }
 
 .device-mode-content-area {
     flex: auto;
     position: relative;
     margin: 0;
 }
 
 .device-mode-screen-area {
     position: absolute;
@@ skipping 101 matching lines @@
 .device-mode-blueprint > span {
     transition: opacity 150ms;
     opacity: 0;
     padding: 3px;
 }
 
 .device-mode-blueprint:hover > span {
     opacity: 1;
     display: initial;
 }