Update app.py

app.py

@@ -1,31 +1,46 @@
 import streamlit as st 
 
-# More specific CSS targeting for sticky header
+# Create a container for the sticky header
+header_container = st.container()
+
+# Create a separate container for the main content
+main_container = st.container()
+
+# Set up a custom CSS using st.markdown for the containers
 st.markdown("""
 <style>
-    /* Target the main header container */
-    [data-testid="stHeader"] {
-        position: fixed;
-        top: 0px;
-        left: 0px;
-        right: 0px;
-        z-index: 1000;
+    div[data-testid="stVerticalBlock"] > div:nth-child(1) {
+        position: sticky;
+        top: 0;
         background-color: white;
-    }
-    
-    /* Add padding to the main content to prevent it from being hidden under the header */
-    [data-testid="stAppViewContainer"] > .main {
-        padding-top: 3rem;
-    }
-    
-    /* Ensure the sidebar isn't affected by the fixed header */
-    [data-testid="stSidebar"] {
         z-index: 999;
-        padding-top: 3rem;
+        padding: 1rem;
+        border-bottom: 1px solid #f0f0f0;
+    }
+    /* Adjust main content padding */
+    div[data-testid="stVerticalBlock"] > div:nth-child(2) {
+        padding-top: 1rem;
     }
+    /* Hide default Streamlit header if desired */
+    header {visibility: hidden;}
 </style>
 """, unsafe_allow_html=True)
 
+# Add content to the sticky header container
+with header_container:
+    st.title("My App with Sticky Header")
+    # Add any other header elements here
+    st.markdown("---")  # Optional divider
+
+# Add content to the main container
+with main_container:
+    # Your main app content goes here
+    st.write("Main content starts here")
+    
+    # Add some sample content to demonstrate scrolling
+    for i in range(20):
+        st.write(f"Content line {i}")
+