In the ‘Survey colors' panel, you can change the color of the Title, Text, Question text, Answer Text, Full background, Lines & Borders, Question background, Answers background.
To change a field's color color, you simply have to click the corresponding color. A color selector will appear. You can pick the desired color with the mouse button, and you have to click select once you've chosen a color.
To leave the color picker, simply click on the page outside the picker.
In this tab you can change the text style and size.
Width and paddings
In this tab you can change the survey width, question and answer paddings, and the logo spacing from bottom. Once you're finished with the design, click ‘Next' and you'll land at STEP 4.