final fix

app.py

@@ -1508,23 +1508,21 @@ CANVAS_JS = r"""
 # --app-h is a *fixed pixel* stand-in for 100vh. On HF Spaces the app runs in a <gradio-app>
 # iframe that resizes to its content, so `vh` units feed back and grow forever. Pinning a pixel
 # height from window.innerHeight (updated only on real resize) breaks that loop.
+# --app-h is a fixed-px stand-in for the app height.
+#   Direct URL (top-level page): use the real available viewport -> full-height, scrollless.
+#   Embedded in an iframe (e.g. the HF Space page): the iframe is content-sized, so innerHeight is
+#   circular and unrelated to the visible area — we can't know it, so we use a sensible fixed height.
+EMBED_HEIGHT_PX = 720
 HEIGHT_SYNC_JS = (
-    "(function(){var h=0,dbg=null;"
-    "function s(){"
-    "var el=document.querySelector('.gradio-container');"
-    "var top=el?el.getBoundingClientRect().top:0;"  # space taken by HF/host header above the app
+    "(function(){var embedded=window.top!==window.self;var h=0;function s(){"
+    "if(embedded){h=" + str(EMBED_HEIGHT_PX) + ";}"
+    "else{var el=document.querySelector('.gradio-container');"
+    "var top=el?el.getBoundingClientRect().top:0;"
     "var a=Math.max(320, window.innerHeight - Math.max(0, top));"
-    "if(!h||a<h)h=a;"  # only ever shrink: an auto-sizing embed can't make us run away
-    "document.documentElement.style.setProperty('--app-h', h + 'px');"
-    "try{if(!dbg&&document.body){dbg=document.createElement('div');"
-    "dbg.style.cssText='position:fixed;left:2px;bottom:2px;z-index:99999;background:#000;"
-    "color:#0f0;font:10px monospace;padding:2px 5px;opacity:.85;pointer-events:none';"
-    "document.body.appendChild(dbg);}"
-    "if(dbg)dbg.textContent='ih='+window.innerHeight+' top='+Math.round(top)+' appH='+h"
-    "+' bsh='+document.body.scrollHeight+' iframe='+(window.top!==window.self)+' gc='+(!!el);"
-    "}catch(e){}}"
+    "if(!h||a<h)h=a;}"  # only ever shrink on the direct URL (never chase an auto-sizing parent)
+    "document.documentElement.style.setProperty('--app-h', h + 'px');}"
     "s();window.addEventListener('resize', s);window.addEventListener('load', s);"
-    "setTimeout(s,300);setTimeout(s,900);setTimeout(s,2000);})();"
+    "setTimeout(s,300);setTimeout(s,900);})();"
 )
 HEAD = (
     "<style>\n" + CSS + "\n</style>\n"