You can customize the background color of the form field customers are filling in in your booking page.
1. Go to Settings>Colors and styles
2. Input the following rules in the section Custom CSS (Advanced)
.bookeocss .inputFieldFocused {
background-color: #FF0000;
}
to set it to red, for example.
3. Save
These are only sample colors. Colors can be expressed by standard color name (example: yellow ; see a list of possible color names here: http://www.w3schools.com/cssref/css_colornames.asp ), or code (example: #FF6666 ; see http://www.w3schools.com/tags/ref_colorpicker.asp )