chat: bottom input matches hero — floating card, text-xl, Send label

Replaces the compact dark footer bar with a floating rounded card
(same rgba glass style as the hero input) centred at max-w-3xl.
Textarea grows to rows=2, text-xl with transparent background.
Stop/Send buttons gain a text label to match the hero variant.
A gradient fade from #0F0027 to transparent behind the card
prevents content bleeding through.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/components/ChatInput.tsx

@@ -101,63 +101,69 @@ export function ChatInput({
     );
   }
 
-  // "bottom" variant — sticky footer bar once a conversation is in progress
+  // "bottom" variant — floating card anchored to bottom, matching hero style
   return (
-    <div className="sticky bottom-0 w-full" style={{ backgroundColor: "#0F0027" }}>
-      <form
-        onSubmit={handleSubmit}
-        className="mx-auto max-w-3xl flex items-center gap-3 px-4 py-3"
+    <div className="sticky bottom-0 w-full px-4 pb-4 pt-2" style={{ background: "linear-gradient(to top, #0F0027 60%, transparent)" }}>
+      <div
+        className="mx-auto max-w-3xl rounded-2xl border border-white/10"
+        style={{ backgroundColor: "rgba(255,255,255,0.08)" }}
       >
-        {/* Download conversation button */}
-        {hasMessages && (
-          <button
-            type="button"
-            onClick={onExportConversation}
-            className="shrink-0 p-2 rounded-lg text-white/70 hover:text-white hover:bg-white/10 transition-colors"
-            title="Download conversation"
-            aria-label="Download conversation"
-          >
-            <DownloadIcon />
-          </button>
-        )}
-
-        {/* Text input */}
-        <div className="flex-1">
+        <form onSubmit={handleSubmit} className="flex flex-col gap-0 px-5 pt-4 pb-3">
+          {/* Large textarea — same scale as hero input */}
           <textarea
             value={query}
             onChange={(e) => setQuery(e.target.value)}
             onKeyDown={handleKeyDown}
             disabled={isStreaming}
             placeholder={isStreaming ? "Waiting for response..." : "Ask a compliance question..."}
-            rows={1}
-            className="w-full resize-none rounded-lg border-0 bg-white/15 px-4 py-2.5 text-sm text-white placeholder-white/50 outline-none focus:bg-white/20 focus:ring-0 disabled:opacity-50 disabled:cursor-not-allowed transition-colors"
+            rows={2}
+            className="w-full resize-none border-0 bg-transparent text-xl text-white placeholder-white/40 outline-none focus:ring-0 disabled:opacity-50 disabled:cursor-not-allowed leading-relaxed"
             aria-label="Chat input"
           />
-        </div>
 
-        {/* Stop button while streaming, send button otherwise */}
-        {isStreaming ? (
-          <button
-            type="button"
-            onClick={onStop}
-            className="shrink-0 p-2 rounded-lg text-white/80 hover:text-white hover:bg-white/10 transition-colors"
-            title="Stop generating"
-            aria-label="Stop generating"
-          >
-            <StopIcon />
-          </button>
-        ) : (
-          <button
-            type="submit"
-            disabled={!canSubmit}
-            className="shrink-0 p-2 rounded-lg text-white/80 hover:text-white hover:bg-white/10 disabled:opacity-30 disabled:cursor-not-allowed transition-colors"
-            title="Send message"
-            aria-label="Send message"
-          >
-            <SendIcon />
-          </button>
-        )}
-      </form>
+          {/* Action row */}
+          <div className="flex items-center justify-between pt-2">
+            {/* Download conversation button */}
+            {hasMessages && (
+              <button
+                type="button"
+                onClick={onExportConversation}
+                className="p-2 rounded-lg text-white/50 hover:text-white hover:bg-white/10 transition-colors"
+                title="Download conversation"
+                aria-label="Download conversation"
+              >
+                <DownloadIcon />
+              </button>
+            )}
+            {!hasMessages && <div />}
+
+            {/* Stop / Send */}
+            {isStreaming ? (
+              <button
+                type="button"
+                onClick={onStop}
+                className="flex items-center gap-2 px-4 py-2 rounded-xl text-sm font-medium text-white/90 hover:text-white bg-white/10 hover:bg-white/20 transition-colors"
+                title="Stop generating"
+                aria-label="Stop generating"
+              >
+                <StopIcon />
+                <span>Stop</span>
+              </button>
+            ) : (
+              <button
+                type="submit"
+                disabled={!canSubmit}
+                className="flex items-center gap-2 px-4 py-2 rounded-xl text-sm font-medium text-white/90 hover:text-white bg-white/10 hover:bg-white/20 disabled:opacity-30 disabled:cursor-not-allowed transition-colors"
+                title="Send message"
+                aria-label="Send message"
+              >
+                <SendIcon />
+                <span>Send</span>
+              </button>
+            )}
+          </div>
+        </form>
+      </div>
     </div>
   );
 }