The margin-top specifies the top margin of an element. It can have a value in length, % or auto. You can try to run the following code to set the top margin:
Example
<html> <head> </head> <body> <p style = "margin-top: 10px; border:2px solid red;"> This is a paragraph with a specified top margin </p> <p style = "margin-top: 10%; border:2px solid green;"> This is another paragraph with a specified top margin in percent </p> </body> </html>