Here is how to remove padding/line brake from H1 tag:
h1
{
    margin: 0px 0px 0px 0px;
    padding: 0px 0px 0px 0px;
}
 

If you want to remove bold from H1 you can add following line "font-weight:normal;" so your CSS will look like this:
h1
{
    margin: 0px 0px 0px 0px;
    padding: 0px 0px 0px 0px;
    font-weight:normal;"
}