Logo size

Hello,

I’m using the Trident Lite theme and I wonder how to change the logo size in the customizer part of the theme.
In “custom.css” I’ve changed in Header Style :

#masthead .header-logo {
	float: left;
	max-width: 390px;
	height: 150px;
	margin: 20px 0 20px 20px;

by

#masthead .header-logo {
	float: left;
	max-width: 1500px;
	height: 400px;
	margin: 20px 0 20px 20px;

but the header is bigger, and my logo picture still the same (a little size).

Waiting for your answer ?? thx