Fix epicker's transparency issue with dark theme

Related discussion:
- https://github.com/uBlockOrigin/uBlock-issues/discussions/1963#discussioncomment-2120210

Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/2062

src/css/themes/default.css

@@ -299,8 +299,6 @@
 
 /* https://material.io/design/color/dark-theme.html */
 :root.dark {
-    color-scheme: dark;
-
     --elevation-down-surface: black;
     --elevation-down1-opacity: 16%;
     --elevation-down2-opacity: 32%;
@@ -373,6 +371,12 @@
     --logger-redirected-surface: rgb(var(--yellow-5) / 40%);
 }
 
+:root.dark input,
+:root.dark select,
+:root.dark textarea {
+    color-scheme: dark;
+}
+
 /*
  * Shared declarations
  * */