At EmailsAndSurveys you can import your brand, and website colors and set default faults which is highly recommended. This will make creating email template much easier as your website colors will be defaulted in the color pallets
You will be prompted to import your brand during registration by clicking the up arrow you see below, but it also can be done after registration, but clicking your initials, go to My Profile, and then My Brand on the right side of the page. You can edit or delete your brand or add another one by clicking the button "Add Your Brand Name Automatically".
Pick your logo, this will display in the logo directory in My Drive.
You can filter the pages of images you would like to import
Set the colors you would like to use in your Email Template. You can still pick any color, but these will be your default colors