18. (5 points)
In a football match between Italy and Brazil, the ratio of spectators supporting Italy to those supporting Brazil was 5:4. At halftime, due to a large score difference, $\frac{1}{3}$ of the spectators left the venue, and the remaining spectators had a ratio of 3:1 for those supporting Italy to those supporting Brazil. If 35 spectators who left supported Italy, then the total number of spectators initially was $\qquad$ people.
$630$