UI refinements (#2859)

## Description:

UI Refinements requested by @evanpelle  check https://ui.openfront.dev

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

w.o.n

src/client/FlagInputModal.ts

@@ -18,7 +18,7 @@ export class FlagInputModal extends BaseModal {
   render() {
     const content = html`
       <div
-        class="h-full flex flex-col bg-black/40 backdrop-blur-md rounded-2xl border border-white/10 overflow-hidden"
+        class="h-full flex flex-col bg-black/60 backdrop-blur-md rounded-2xl border border-white/10 overflow-hidden"
       >
         <div
           class="flex items-center mb-4 pb-2 border-b border-white/10 gap-2 shrink-0 p-6"
@@ -54,7 +54,7 @@ export class FlagInputModal extends BaseModal {
 
         <div class="flex justify-center w-full px-6 pb-4 shrink-0">
           <input
-            class="h-12 w-full max-w-md border border-white/10 bg-black/40
+            class="h-12 w-full max-w-md border border-white/10 bg-black/60
             rounded-xl shadow-inner text-xl text-center focus:outline-none
             focus:ring-2 focus:ring-blue-500/50 focus:border-blue-500 text-white placeholder-white/30 transition-all"
             type="text"