Adjust font contrast to be more accessible.

chrome/browser/resources/hotword_audio_verification/style.css

 /* Copyright 2014 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. */
 
 /* TODO(xdai): Remove hard-coded font-family for 'Roboto'. */
 
 * {
   box-sizing: border-box;
   color: rgba(0, 0, 0, .54);
   font-family: Roboto, 'Noto Sans', sans-serif;
@@ skipping 51 matching lines @@
 
 #start-container .buttonbar button {
   height: 100%;
   margin: 0;
   padding: 0 8px;
   width: 100%;
 }
 
 a {
   -webkit-app-region: no-drag;
-  color: rgb(66, 133, 244);
+  color: rgb(51, 103, 214);
   text-decoration: none;
 }
 
 button {
   -webkit-app-region: no-drag;
 }
 
 body {
   -webkit-app-region: drag;
   background: #ddd;
@@ skipping 170 matching lines @@
 .buttonbar button:disabled {
   opacity: .5;
 }
 
 .buttonbar button.grayed-out {
   color: rgba(0, 0, 0, .28);
   text-transform: none;
 }
 
 .buttonbar button.primary {
-  color: rgb(66, 133, 244);
+  color: rgb(51, 103, 214);
 }
 
 .buttonbar .left {
   float: left;
   text-align: left;
 }
 
 .buttonbar .left button:first-child {
   margin-left: 0;
 }
@@ skipping 32 matching lines @@
 
 .buttonbar .message .text {
   color: rgba(0, 0, 0, .54);
   display: inline-block;
   line-height: 18px;
   padding-top: 2px;
   vertical-align: top;
 }
 
 .buttonbar .message.error .text {
-  color: rgb(219, 68, 55);
+  color: rgb(213, 0, 0);
 }
 
 .close {
   -webkit-app-region: no-drag;
   background: -webkit-image-set(
       url(../images/ic-x-white-1x.png) 1x,
       url(../images/ic-x-white-2x.png) 2x)
       center center no-repeat;
   border: none;
   float: right;
@@ skipping 25 matching lines @@
   background: none;
   border: none;
   color: rgb(58, 218, 255);
   float: right;
   height: 32px;
   margin-left: 18px;
   min-width: 56px;
   padding: 0 8px 0 8px;
   text-transform: uppercase;
 }