Update app.py

app.py

@@ -1,5 +1,82 @@
 import streamlit as st 
 
+import time
+
+# --- Custom CSS ---
+# !!! IMPORTANT !!!
+# 1. YOU MUST VERIFY AND ADJUST THE SELECTORS BELOW USING YOUR BROWSER'S INSPECTOR.
+# 2. THE HEADER_HEIGHT MUST ACCURATELY REFLECT YOUR HEADER'S ACTUAL HEIGHT.
+
+# Use the developer tools to find your header's actual height.
+# Inspect the header element, go to the "Computed" tab in styles, and find its height.
+HEADER_HEIGHT = "60px"  # EXAMPLE: Adjust this (e.g., "56px", "4rem")
+
+# ---- SELECTOR FOR THE HEADER ----
+# Try this first (common for recent Streamlit versions):
+HEADER_SELECTOR = 'header[data-testid="stHeader"]'
+# If that doesn't work, inspect and find the correct one.
+# It might be just 'header', or a div with a specific class.
+# Example if using a class: HEADER_SELECTOR = 'div.my-custom-looking-header-class'
+
+# ---- SELECTOR FOR THE MAIN CONTENT AREA THAT NEEDS PADDING ----
+# This targets the first direct div child of the stAppViewContainer,
+# which often holds the main scrollable content.
+MAIN_CONTENT_SELECTOR = 'section[data-testid="stMainBlockContainer"] > div:nth-child(1)'
+# Alternative if the above doesn't work or if your content is further nested:
+# MAIN_CONTENT_SELECTOR = 'section[data-testid="stAppViewContainer"] .main-content-wrapper-class'
+# Or, very commonly, Streamlit wraps main content in a div with class "block-container":
+# MAIN_CONTENT_SELECTOR = 'section[data-testid="stAppViewContainer"] .block-container'
+# MAIN_CONTENT_SELECTOR = '.main .block-container' # A more general selector for block-container
+
+custom_css = f"""
+<style>
+    /* Making the Streamlit header sticky */
+    {HEADER_SELECTOR} {{
+        position: -webkit-sticky !important; /* For Safari */
+        position: sticky !important;
+        top: 0 !important;
+        z-index: 9999 !important; /* Very high z-index */
+        background-color: #0f1116 !important; /* Or your app's header background color */
+        /* Add a subtle shadow to make it feel more distinct when content scrolls under */
+        /* box-shadow: 0 2px 4px -1px rgba(0,0,0,0.1); */
+    }}
+
+    /* Adding padding to the main content area to prevent overlap with the sticky header */
+    {MAIN_CONTENT_SELECTOR} {{
+        padding-top: {HEADER_HEIGHT} !important;
+    }}
+
+    /* Optional: If your app is set to wide mode and the header isn't spanning full width */
+    /* This might be needed if the sticky positioning affects its width calculation. */
+    /*
+    {HEADER_SELECTOR} {{
+        width: 100% !important;
+    }}
+    */
+</style>
+"""
+
+# Inject CSS as early as possible in your app
+st.markdown(custom_css, unsafe_allow_html=True)
+
+# --- Your Streamlit App ---
+st.title("App with Attempted Sticky Header")
+st.sidebar.header("Sidebar")
+st.sidebar.write("Sidebar content here.")
+
+st.header("Main Content Section")
+st.write(f"The header should be sticky. This content section has a top padding of approximately {HEADER_HEIGHT} to compensate for the header.")
+st.info(f"Header Selector Used: `{HEADER_SELECTOR}`")
+st.info(f"Main Content Selector Used: `{MAIN_CONTENT_SELECTOR}`")
+
+
+if st.button("Run Process (for status widget)"):
+    with st.spinner("Processing..."):
+        time.sleep(2)
+    st.success("Process finished!")
+
+for i in range(60):
+    st.write(f"Scrollable line of content {i + 1}.")
 
 # --- SHARED ON ALL PAGES ---
 #st.logo(image="images/menu_book_60dp_75FBFD.png")