To change Site Title (text, size, color, font…) in Squarespace, you can follow these.
A. Change Site Title
To change the site title to another text, you can follow this guide
B. Change Size Title Size
To change the site title size, you can follow this guide.
C. Change Site Title Color
#1. First, click EDIT on the top left of the Header
#2. Click on the Site Styles icon on the top right of the screen.
#3. Next, choose COLORS
#4. Click on your page color theme
#5. Click on Site Title – Header to change your title color
D. Site Title Font CSS
To change Site Title font with CSS code, you can use this code to Custom CSS box. Replace futura-pt with font what you want.
a#site-title {
font-family: futura-pt !important;
}