alterações de melhorias

src/public/js/dark-mode.js

@@ -1,14 +1,29 @@
 // Dark Mode Controller — Unified for all Chatc2 pages
 (function() {
+  // Detecta preferência do sistema
+  var osPrefersDark = window.matchMedia('(prefers-color-scheme: dark)');
+  var manualOverride = localStorage.getItem('chatc2_dark_mode_manual');
+
+  // Decide tema inicial: manual > preferência OS > claro
+  function getInitialTheme() {
+    if (manualOverride !== null) return manualOverride === 'true';
+    return osPrefersDark.matches;
+  }
+
   // Apply on load immediately (FOUC prevention)
-  if (localStorage.getItem('chatc2_dark_mode') === 'true') {
+  if (getInitialTheme()) {
     document.documentElement.classList.add('dark-mode-pending');
   }
 
-  function applyTheme(enable) {
+  function applyTheme(enable, isManual) {
     document.documentElement.classList.remove('dark-mode-pending');
-    document.body && document.body.classList.toggle('dark-mode', enable);
+    if (document.body) {
+      document.body.classList.toggle('dark-mode', enable);
+    }
     localStorage.setItem('chatc2_dark_mode', enable ? 'true' : 'false');
+    if (isManual) {
+      localStorage.setItem('chatc2_dark_mode_manual', enable ? 'true' : 'false');
+    }
     document.querySelectorAll('.dark-mode-toggle').forEach(function(btn) {
       btn.innerHTML = enable ? '☀️ Claro' : '🌙 Escuro';
     });
@@ -16,21 +31,28 @@
 
   window.darkModeToggle = function() {
     var isDark = localStorage.getItem('chatc2_dark_mode') === 'true';
-    applyTheme(!isDark);
+    applyTheme(!isDark, true); // toggle manual
   };
 
-  window.darkModeApply = function(enable) { applyTheme(enable); };
+  window.darkModeApply = function(enable) { applyTheme(enable, false); };
 
   window.darkModeIsDark = function() {
     return localStorage.getItem('chatc2_dark_mode') === 'true';
   };
 
-  // Apply stored preference after DOM ready
+  // Reage a mudanças no tema do sistema (só quando não há override manual)
+  osPrefersDark.addEventListener('change', function(e) {
+    if (localStorage.getItem('chatc2_dark_mode_manual') === null) {
+      applyTheme(e.matches, false);
+    }
+  });
+
+  // Apply after DOM ready
   if (document.readyState === 'loading') {
     document.addEventListener('DOMContentLoaded', function() {
-      applyTheme(localStorage.getItem('chatc2_dark_mode') === 'true');
+      applyTheme(getInitialTheme(), false);
     });
   } else {
-    applyTheme(localStorage.getItem('chatc2_dark_mode') === 'true');
+    applyTheme(getInitialTheme(), false);
   }
 })();