Enhance UI and functionality across multiple components

- Updated styles in style.css to improve overall design consistency and introduced CSS variables for better theming.
- Refined ChatWindow.vue with improved no-conversation styling and adjusted image borders for a cleaner look.
- Enhanced HistoryView.vue and InboxView.vue with new panel styles for better user experience and readability.
- Revamped LoginForm.vue to provide a more engaging user interface with a landing page layout and cookie-based profile persistence.
- Improved MenuBar.vue and SearchView.vue with active state indicators and refined item displays for better navigation.
- Added logout functionality in chat store and server routes to manage user sessions effectively.
- Introduced a new mockup view route for design previews.

These changes collectively enhance the user experience and visual appeal of the application.

client/src/components/ImprintContainer.vue

@@ -55,30 +55,53 @@ Thanks for the flag icons to <a href="https://flagpedia.net">flagpedia.net</a>
   left: 0;
   right: 0;
   bottom: 0;
-  background: rgba(0, 0, 0, 0.5);
+  background: rgba(18, 26, 21, 0.52);
   display: flex;
   align-items: center;
   justify-content: center;
-  z-index: 1000;
+  z-index: 1200;
+  padding: 20px;
 }
 
 .imprint-content {
-  background: white;
-  padding: 20px;
+  background: #ffffff;
+  border: 1px solid #d7dfd9;
+  border-radius: 14px;
+  padding: 24px 20px 20px;
   max-width: 600px;
   max-height: 80vh;
   overflow-y: auto;
   position: relative;
+  box-shadow: 0 24px 60px rgba(18, 26, 21, 0.18);
 }
 
 .close-button {
   position: absolute;
   top: 10px;
   right: 10px;
-  background: none;
-  border: none;
-  font-size: 24px;
+  width: 32px;
+  height: 32px;
+  background: #f6f9f7;
+  border: 1px solid #d7dfd9;
+  border-radius: 8px;
+  font-size: 22px;
+  line-height: 1;
   cursor: pointer;
 }
-</style>
 
+.imprint-content :deep(h1) {
+  margin-bottom: 12px;
+  font-size: 20px;
+  color: #18201b;
+}
+
+.imprint-content :deep(p) {
+  margin-bottom: 12px;
+  color: #344038;
+  line-height: 1.5;
+}
+
+.imprint-content :deep(a) {
+  color: #245c3a;
+}
+</style>