Change bubble size in altair without changing font size

Question

I am trying to create a altair bubble chart. The sample code and sample dataframe is below: I want the size of the bubble based on Market_cap and put names of companies alongside. The problem is font size of names is also changing as per the bubble size.

How can this I create this bubble chart with different bubble size but same size of font for Company names?

df = pd.DataFrame({ 'Company' : ['Apple', 'Microsoft', 'Meta', 'Nvidia'],
                   'Rev_perct' : [30, 50, 90, 10],
                  'Score' : [8, 5, 10, 4],
                  'Market_Cap' : [2000, 1000, 500, 800]
})

Graph_1 = alt.Chart(df).mark_circle(size = 100).encode( y = alt.Y('Rev_perct'), x = alt.X('Score'), 
                                                       color=alt.condition(
                                                       "datum.Rev_perct > 30"
                                                       "& datum.Score > 6",  
                                                        alt.value('red'),     
                                                       alt.value('green')          
                                                       ), size='Market_Cap')

Text_1 = Graph_1.mark_text( align='center',
   baseline='line-top', color = 'black', fontSize = 12, angle = 0,
   dy=10, dx= -5    
).encode(text='Company:O')

(Graph_1 + Text_1).properties(width = 800, height = 400)

This is the resulting graph i am getting now-