Update app.py

app.py

@@ -1,3 +1,6 @@
+import base64
+from pathlib import Path
+
 import streamlit as st
 from dotenv import load_dotenv
 
@@ -35,6 +38,130 @@ with st.sidebar:
         logout()
         st.rerun()
 
+    st.markdown(
+        """
+        <style>
+        .private-mode-banner {
+            padding: 0.75rem 1rem;
+            margin-top: 0.5rem;
+            border-radius: 0.85rem;
+            background: linear-gradient(125deg, rgba(91, 33, 182, 0.85), rgba(132, 94, 247, 0.55));
+            border: 1px solid rgba(132, 94, 247, 0.35);
+            color: #fff;
+            font-weight: 500;
+            box-shadow: 0 10px 24px rgba(82, 46, 173, 0.28);
+            animation: privateBannerSlide 0.55s ease forwards, privateBannerFade 3.3s ease 1.75s forwards;
+        }
+
+        .private-mode-banner-content {
+            display: flex;
+            align-items: flex-start;
+            gap: 0.85rem;
+        }
+
+        .private-mode-banner-copy {
+            display: flex;
+            flex-direction: column;
+            gap: 0.15rem;
+        }
+
+        .private-mode-icon {
+            width: 64px;
+            min-width: 48px;
+            max-width: 20%;
+            filter: drop-shadow(0 6px 16px rgba(16, 13, 61, 0.45));
+            opacity: 0.95;
+        }
+
+        .private-mode-banner small {
+            display: block;
+            opacity: 0.85;
+            font-weight: 400;
+            margin-top: 0.25rem;
+            letter-spacing: 0.01em;
+        }
+
+        @media (max-width: 320px) {
+            .private-mode-icon {
+                display: none;
+            }
+        }
+
+        @keyframes privateBannerSlide {
+            0% { transform: translateY(-12px); opacity: 0; }
+            60% { transform: translateY(2px); opacity: 1; }
+            100% { transform: translateY(0); opacity: 1; }
+        }
+
+        @keyframes privateBannerFade {
+            to { opacity: 0; }
+        }
+
+        @keyframes privateToggleGlow {
+            0% { box-shadow: 0 0 0 rgba(132, 94, 247, 0.0); }
+            40% { box-shadow: 0 0 24px rgba(132, 94, 247, 0.55); }
+            100% { box-shadow: 0 0 0 rgba(132, 94, 247, 0.0); }
+        }
+        </style>
+        """,
+        unsafe_allow_html=True,
+    )
+
+    prev_private_mode = st.session_state.get("_private_mode_prev", st.session_state.get("private_mode_enabled", False))
+    banner_slot = st.empty()
+
+    private_mode_default = st.session_state.get("private_mode_enabled", False)
+    private_mode = st.toggle(
+        "Private mode",
+        value=private_mode_default,
+        key="private_mode_enabled",
+        help="Skip saving prompts, jobs, and generated media to shared libraries."
+    )
+    just_enabled_private_mode = private_mode and not prev_private_mode
+    just_disabled_private_mode = (not private_mode) and prev_private_mode
+
+    if just_enabled_private_mode:
+        st.markdown(
+            """
+            <style>
+            div[data-testid="stSidebar"] div[data-testid="stToggle"] label {
+                animation: privateToggleGlow 2.45s ease-out 0s 1;
+                border-radius: 0.5rem;
+            }
+            </style>
+            """,
+            unsafe_allow_html=True,
+        )
+        icon_data_url = ""
+        try:
+            icon_path = Path(__file__).resolve().parent / "assets" / "private-mode.png"
+            icon_data_url = "data:image/png;base64," + base64.b64encode(icon_path.read_bytes()).decode("utf-8")
+        except Exception:
+            icon_data_url = ""
+
+        icon_html = f'<img src="{icon_data_url}" alt="Private mode icon" class="private-mode-icon" />' if icon_data_url else ""
+        banner_slot.markdown(
+            f"""
+            <div class="private-mode-banner">
+                <div class="private-mode-banner-content">
+                    {icon_html}
+                    <div class="private-mode-banner-copy">
+                        Private mode is live for this session.
+                        <small>We'll keep new generations off shared storage until you disable it.</small>
+                    </div>
+                </div>
+            </div>
+            """,
+            unsafe_allow_html=True,
+        )
+    elif just_disabled_private_mode:
+        banner_slot.empty()
+
+    st.session_state["_private_mode_prev"] = private_mode
+
+    if private_mode:
+        st.caption("Private mode keeps this session's generations ephemeral—nothing is stored in the AI Library or external storage.")
+
     section = st.radio(" ", ["Gen AI", "AI Library"], index=0, horizontal=True, key="main_section")
 
 # ---------------------------- Gen AI ---------------------------------