That’s the post’s footer meta info which is styled around line 1132 of the style.css file:
.entry-footer-meta {
margin: 2em 0;
padding: 0.5em 0.75em;
border-left: 4px solid #dedede;
background-color: #f5f5f5;
font: italic 11px verdana, sans-serif;
font-size: 0.688rem;
line-height: 1.5;
clear:both;
}