fix(theme): dark-theme login box, feedback messages, and nav logout link

- Override the Login plugin's white #grav-login box to use dark theme tokens
- Style flash/form notices (.notices, #messages .toast) globally on-theme;
  override markdown-notices' bright per-colour variant backgrounds so error/
  success/warning messages stay dark with a coloured left border
- Add a Logout link to the main nav (authenticated-only, plain nav style);
  no login link in the menu

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Rw9Tceo6DSzVqWKkjVJpHZ

themes/intotheeast/css/style.css

@@ -791,8 +791,65 @@ body::after {
 
 .feed-map-link:hover { color: var(--color-accent-hover); }
 
+/* ── Feedback / notification messages ────────────────────────────────────────── */
+
+/* Grav renders feedback two ways and the theme styled neither globally:
+   - Form/flash messages as <div class="notices success|error|warning green|red|yellow">
+     (Form plugin form-messages.html.twig; also markdown-notices output).
+   - Plain flash messages as #messages .toast .toast-error|success|warning (quark
+     partials/messages.html.twig, resolved since this theme has none of its own).
+   Without these rules they fell back to light admonition boxes that clash with the
+   dark theme (first noticed on /login). Kept on-theme with a status-coloured
+   left border. */
+.notices,
+#messages .toast {
+    padding: 1rem 1.1rem;
+    border-radius: var(--radius-md);
+    font-size: var(--text-base);
+    margin: 0 0 var(--space-5);
+    background: var(--color-canvas);
+    color: var(--color-ink);
+    border: 1px solid var(--color-border);
+    border-left: 4px solid var(--color-accent);
+}
+.notices p,
+#messages .toast p { margin: 0; }
+
+/* markdown-notices sets bright per-colour backgrounds on .notices.red / .yellow /
+   .green / .blue at (0,2,0). Override each variant at equal specificity (this
+   sheet loads later) so the dark canvas + cream text always win — only the
+   left-border colour signals status. */
+.notices.error, .notices.red,
+.notices.success, .notices.green,
+.notices.warning, .notices.yellow,
+.notices.blue,
+#messages .toast-error,
+#messages .toast-success,
+#messages .toast-warning {
+    background: var(--color-canvas);
+    color: var(--color-ink);
+    border-left-width: 4px;
+    border-left-style: solid;
+}
+.notices.error, .notices.red,
+#messages .toast-error { border-left-color: var(--color-error); }
+.notices.success, .notices.green,
+#messages .toast-success { border-left-color: var(--color-accent); }
+.notices.warning, .notices.yellow,
+#messages .toast-warning { border-left-color: #c98a2e; }
+.notices.blue { border-left-color: var(--color-accent); }
+
 /* ── Login form ─────────────────────────────────────────────────────────────── */
 
+/* Neutralise the Login plugin's built-in white box (#grav-login in
+   plugin://login/css/login.css) so the wrapper matches the dark theme. */
+#grav-login {
+    background: var(--color-canvas);
+    border: 1px solid var(--color-border);
+    border-radius: var(--radius-md);
+    color: var(--color-ink);
+}
+
 .login-form { max-width: 400px; margin: var(--space-8) auto; padding: 0 var(--space-4); }
 .login-form .form-field { margin-bottom: var(--space-5); }
 .login-form .form-label label { display: block; font-size: var(--text-sm); font-weight: 600; margin-bottom: var(--space-2); }