Log in to your Shopify Admin Panel. Go to Online Store > Themes > Customize.
On the theme editing page, select Theme Settings. When you select Color, all the colors in your theme will be displayed. You can adjust them to suit your preferences.
In the theme editor, navigate to the section where you want to change the background. Go to Online Store > Themes > Customize
Look for background color settings (commonly found under “Style” or “Design” tabs). Choose a color from the palette or enter a hex code (e.g., #EFF0F5). Save the changes