feat: move footer privacy note behind PRIVACY overlay button

DeepDrftPublic.Client/Layout/DeepDrftFooter.razor

@@ -4,8 +4,34 @@
         <ul class="deepdrft-footer-links">
             <li><a href="/about">About</a></li>
             <li><a href="#">Contact</a></li>
+            <li><button class="deepdrft-footer-privacy-btn" @onclick="@OpenPrivacy" type="button" aria-haspopup="dialog">Privacy</button></li>
         </ul>
         <div class="deepdrft-footer-copy">© 2026 Deep DRFT</div>
     </div>
-    <p class="deepdrft-footer-privacy">We keep a random tag in your browser so we can count how many people a track reaches — not who they are. No account, no name, nothing personal, nothing shared with anyone else. Clear your browser data and the tag&#8217;s gone.</p>
-</footer>
+</footer>
+
+<MudOverlay Visible="@_privacyOpen"
+            DarkBackground="true"
+            Modal="true"
+            OnClick="@ClosePrivacy"
+            Class="deepdrft-privacy-overlay">
+    <div class="deepdrft-privacy-modal" @onclick:stopPropagation="true">
+        <div class="deepdrft-privacy-modal-header">
+            <span class="deepdrft-privacy-modal-title">Privacy</span>
+            <MudIconButton Icon="@Icons.Material.Filled.Close"
+                           Size="Size.Small"
+                           Color="Color.Default"
+                           OnClick="@ClosePrivacy"
+                           aria-label="Close privacy note"
+                           Class="deepdrft-privacy-modal-close" />
+        </div>
+        <p class="deepdrft-privacy-modal-body">We keep a random tag in your browser so we can count how many people a track reaches — not who they are. No account, no name, nothing personal, nothing shared with anyone else. Clear your browser data and the tag&#8217;s gone.</p>
+    </div>
+</MudOverlay>
+
+@code {
+    private bool _privacyOpen;
+
+    private void OpenPrivacy() => _privacyOpen = true;
+    private void ClosePrivacy() => _privacyOpen = false;
+}

DeepDrftPublic.Client/Layout/DeepDrftFooter.razor.css

@@ -57,16 +57,26 @@
     color: var(--deepdrft-muted);
 }
 
-.deepdrft-footer-privacy {
+/* PRIVACY trigger — visually matches the footer <a> links (same font, size, casing, colour).
+   Reset all button chrome so it reads as a link, not a button element. */
+.deepdrft-footer-privacy-btn {
     font-family: var(--deepdrft-font-mono);
-    font-size: 0.55rem;
-    letter-spacing: 0.08em;
+    font-size: 0.62rem;
+    letter-spacing: 0.18em;
+    text-transform: uppercase;
     color: var(--deepdrft-muted);
-    opacity: 0.7;
+    text-decoration: none;
+    transition: color 0.2s;
+    background: none;
+    border: none;
+    padding: 0;
     margin: 0;
-    line-height: 1.6;
+    cursor: pointer;
+    line-height: inherit;
 }
 
+.deepdrft-footer-privacy-btn:hover { color: var(--deepdrft-navy); }
+
 @media (max-width: 440px) {
     .deepdrft-footer {
         padding: 1.5rem;

DeepDrftPublic/wwwroot/styles/deepdrft-styles.css

@@ -917,3 +917,82 @@ body:has(.deepdrft-queue-overlay) {
     max-height: 184px;
     overflow-y: auto;
 }
+
+/* =============================================================================
+   17. PRIVACY OVERLAY
+   Screen-centered modal following the same MudOverlay idiom as the visualizer
+   controls and queue overlays. MudOverlay portals to body — CSS isolation cannot
+   reach portaled content, so chrome lives here in the global sheet.
+   ============================================================================= */
+
+/* Raise above the sticky header (100), player dock (1200), and minimized FAB (1300). */
+.deepdrft-privacy-overlay {
+    z-index: 1400 !important;
+}
+
+/* Mild tint: doubled selector (0,2,0) outranks MudBlazor's .mud-overlay-dark (0,1,0). */
+.deepdrft-privacy-overlay .mud-overlay-scrim.mud-overlay-dark {
+    background-color: rgba(var(--deepdrft-scrim-rgb), var(--deepdrft-modal-scrim-alpha));
+}
+
+.deepdrft-privacy-overlay .mud-overlay-content {
+    max-height: 90vh;
+    overflow: visible;
+}
+
+/* Lock body scroll while the overlay is open. */
+body:has(.deepdrft-privacy-overlay) {
+    overflow: hidden;
+}
+
+/* Panel: compact width, navy-panel ground, thin light border — matches queue/visualizer chrome. */
+.deepdrft-privacy-modal {
+    display: flex;
+    flex-direction: column;
+    width: min(90vw, 480px);
+    background: var(--deepdrft-panel-ground);
+    border: 1px solid var(--deepdrft-border-light);
+    border-radius: 0;
+    backdrop-filter: blur(8px);
+    overflow: hidden;
+}
+
+.deepdrft-privacy-modal-header {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    padding: 0.85rem 0.85rem 0.85rem 1rem;
+    border-bottom: 1px solid var(--deepdrft-border-light);
+}
+
+/* Mono uppercase eyebrow — matches queue modal title. */
+.deepdrft-privacy-modal-title {
+    font-family: var(--deepdrft-font-mono);
+    font-size: 0.72rem;
+    letter-spacing: 0.2em;
+    text-transform: uppercase;
+    color: var(--deepdrft-white);
+    opacity: 0.85;
+}
+
+/* Tuck the close icon flush with the panel edge; keep it subtle. */
+.deepdrft-privacy-modal-close {
+    opacity: 0.6;
+    color: var(--deepdrft-white) !important;
+}
+
+.deepdrft-privacy-modal-close:hover {
+    opacity: 1;
+}
+
+/* Privacy copy: same mono treatment as the former inline paragraph, but readable on dark ground. */
+.deepdrft-privacy-modal-body {
+    font-family: var(--deepdrft-font-mono);
+    font-size: 0.72rem;
+    letter-spacing: 0.06em;
+    line-height: 1.7;
+    color: var(--deepdrft-white);
+    opacity: 0.8;
+    margin: 0;
+    padding: 1rem 1rem 1.25rem;
+}