c1, c2 = st.columns([1, 2])
    if c1.button("🗑️ Clear"):
        st.session_state.history = []; st.rerun()

    if st.session_state.history:
        c2.download_button("📄 Export", export_txt(st.session_state.history),
                           "Math_Mastermind_Solutions.txt", "text/plain")

    with st.form("math_form", clear_on_submit=True):
        q = st.text_area("📝 Enter your math problem:", height=100,
                         placeholder="Example: Solve x² + 5x + 6 = 0",
                         key=f"q_{st.session_state.k}")
        a, b = st.columns([3, 1])
        solve = a.form_submit_button("🧠 Solve", use_container_width=True)
        level = b.selectbox("Level", ["Basic", "Intermediate", "Advanced"], index=1)

        if solve:
            if not q.strip(): st.warning("⚠️ Enter a problem first.")
            else:
                with st.spinner("Solving..."):
                    ans = math_generate(q.strip(), level)
                st.session_state.history.insert(0, {"q": q.strip(), "a": ans, "lvl": level})
                st.session_state.k += 1; st.rerun()

    if not st.session_state.history: return
    st.markdown("### 🧾 Solution History (Latest First)")
    st.markdown("""<style>
    .box{max-height:500px;overflow-y:auto;border:2px solid #4CAF50;padding:12px;background:#f7fbff;border-radius:10px}
    .q{font-weight:700;color:#2E7D32;margin-top:12px}
    .lvl{display:inline-block;background:#FF9800;color:#fff;padding:2px 8px;border-radius:12px;font-size:12px;margin-left:8px}
    .a{white-space:pre-wrap;color:#1B5E20;background:#fff;padding:10px;border-radius:8px;border-left:4px solid #4CAF50;margin:6px 0 14px}
    </style>""", unsafe_allow_html=True)

    html = '<div class="box">'
    for i, h in enumerate(st.session_state.history, 1):
        html += f'<div class="q">Q{i}: {h["q"]}<span class="lvl">{h["lvl"]}</span></div>'
        html += f'<div class="a">{h["a"]}</div>'
    st.markdown(html + "</div>", unsafe_allow_html=True)

if __name__ == "__main__":
    setup_ui()