Where do i insert custom code to reduce the default white space created?

Please follow thread below. My follow up question is in blue.

 Too Much whitespace between color sections
 On the sponsorship page of the website mentioned in private comments…
 there is too much white space between the beginning of the color section and the end of the main menu.
 I placed a simple white space separator at the start of the sponsorship page, designed to give padding , space, between the start of blue color section and the end of the main menu.
 The whitespace separator is value of 1.
 Yet a space of magnitude like 50 or something is occuring!
 I checked the color section; there is no default “padding at the top= ‘high value’”
 Im not sure whats up; can you fix?
 October 10, 2015 at 1:27 pm#516784

Ismael

 Moderator

 Hey elliotstiller!
 Thank you for using Enfold.
 If you put an element outside a color section, the theme will automatically create a section for that particular element. Each section has a top and bottom padding of 50px. Include the hr element inside the color section or try to create a gap via css:
 #av_section_1 {
 margin-top: 100px;
 }
 The Section ID field is going to be handy in this case. Adjust the value as you please.
 Regards,
Ismael

Where do I post that chunk of code he provided? Is it custom css?
What item do I edit– margin, right?– to get the space down to customizable.