try to make the chart square

app.py

@@ -76,7 +76,10 @@ chart_data = chart_data.merge(
     on = "run_accession")
 
 chart = (
-   alt.Chart(chart_data)
+   alt.Chart(
+       chart_data,
+       width = 2000,
+       height = 2000)
    .mark_circle()
    .encode(
        x="expression_1",
@@ -85,7 +88,6 @@ chart = (
        tooltip=["run_accession", "study_accession"]))
 
 st.altair_chart(
-    chart,
-    use_container_width=True)
+    chart)