Let the user's agent figure out selection colors.

css/layout.css

@@ -1414,6 +1414,9 @@ a:only-of-type > .remove {
 .section-style fieldset {
   text-align: left;
 }
+.section-keybinds table {
+  margin: auto;
+}
 #appchanx-settings ul {
   padding: 0;
   #{if _conf["Rounded Edges"] then "border-radius: 3px;" else ""}
@@ -1471,6 +1474,9 @@ article li {
   display: inline-block;
   vertical-align: bottom;
 }
+.option input {
+  width: 100%;
+}
 .optionlabel {
   padding-left: 18px;
 }

css/theme.css

@@ -20,10 +20,6 @@
 .filter_highlight > .reply {
   box-shadow: -5px 0 #{theme["Backlinked Reply Outline"]};
 }
-::#{agent}selection {
-  background: #{theme["Text"]};
-  color: #{backgroundC};
-}
 hr {
   border-bottom: 1px solid #{theme["Reply Border"]};
 }