DevTools: Show a red background under unmatched brackets

third_party/WebKit/Source/devtools/front_end/text_editor/cmdevtools.css

 .CodeMirror {
     line-height: 1.2em !important;
     background-color: transparent !important;
     color: #222;
 }
 
 .CodeMirror-linewidget {
     overflow: visible !important;
 }
 
@@ skipping 95 matching lines @@
 }
 
 .breakpoints-deactivated .cm-breakpoint .CodeMirror-linenumber {
     opacity: 0.5;
 }
 
 .breakpoints-deactivated .cm-breakpoint-disabled .CodeMirror-linenumber {
     opacity: 0.3;
 }
 
-.CodeMirror-matchingbracket {
-    border-bottom: 1px solid black;
-    color: #222 !important;
+div.CodeMirror span.CodeMirror-matchingbracket {
+    background-color: rgba(0, 0, 0, 0.13);
+    color: unset;
 }
 
-.CodeMirror-nonmatchingbracket {
-    color: #222 !important;
+div.CodeMirror span.CodeMirror-nonmatchingbracket {
+    background-color: rgba(255, 0, 0, 0.13);
+    color: unset;
+}
+
+.-theme-with-dark-background div.CodeMirror span.CodeMirror-matchingbracket {
+    border-bottom: 1px solid rgb(217,217,217);
+    background-color:initial;
+}
+
+.-theme-with-dark-background div.CodeMirror span.CodeMirror-nonmatchingbracket {
+    border-bottom: 1px solid rgb(255, 26, 26);
+    background-color:initial;
 }
 
 .cm-whitespace::before {
     position: absolute;
     pointer-events: none;
     color: rgb(175, 175, 175);
 }
 
 .cm-tab {
     position: relative;
@@ skipping 226 matching lines @@
 
 .CodeMirror .auto-complete-text {
     color: rgb(128,128,128);
 }
 
 /** Prevent the codemirror textarea from stealing PageUp events **/
 .CodeMirror textarea {
     resize: none;
     overflow: hidden;
 }