To move "Leave a comment" to the left:

Change this:
Code:
<h2 id="postcomment">Leave a comment</h2>
To this:
Code:
<h2 id="postcomment" style="text-align: left">Leave a comment</h2>
Try one of these 3 options for the margin in css:

Change:

Code:
h2 {
    font-size: 12pt;
    margin-top: 10px;
    color: #000;
    text-align: right;
}
To:
Code:
h2 {
    font-size: 12pt;
    margin: 10px;
    color: #000;
    text-align: right;
}
Or:
Code:
h2 {
    font-size: 12pt;
    margin: 10px 10px 10px 10px;
    color: #000;
    text-align: right;
}
Or you may have to align each side like this:
Code:
h2 {
    font-size: 12pt;
    margin-top: 10px;
    margin-bottom: 10px;
    margin-left: 10px;
    margin-right: 10px;
    color: #000;
    text-align: right;
}