.bannertext supercedes the styles you gave to the individual tag you're showing there.
You only have left and right padding because .bannertext only has left and right padding.
.bannerimage {
	position: relative;
	height: 600px;
	overflow: hidden;
}
/* v This peice of code here supercedes... v */
[b].bannertext {
	position: absolute;
	top: 200px;
	left: 0px;
	background: rgb(0, 0, 0);
	background: rgba(0, 0, 0, 0.7);
	margin-left: 250px;
	padding-right: 30px;
	padding-left: 15px;
	color: white;
	text-decoration: none;
}[/b]
/* v ...this piece of code here v */
.bannertext h1 {
	margin-top: 10px;
	margin-bottom: 0px;
}
.bannertext a {
	color: white;
	margin: 20px;
}
.bannertext a:hover {
	color: red;
	text-decoration: none;
}