Transparent header not working

Hi,

I’m using a Pinboard theme, and already made a transparent (text) png logo. I’m still trying to find the best size for my header. This is not the problem.

I’ve been searching the web for houres to find a CSS code to make the header transparent.

Here is my site.

These are all the Custom CSS codes I filled in. The last 2 codes I filled in I saw on other sites and it should work… :

[ Moderator Note: Please post code or markup snippets between backticks or use the code button. ]

.page-template-template-no-sidebars-php #wrapper,
.page-template-template-blog-no-sidebars-php #wrapper,
.page-template-template-portfolio-no-sidebars-php #wrapper {
	max-width:810px;
}

aside.entry-meta {
 display:none;
}

#sidebar-header {
float: right;
height: 260px;
margin: -80px 0;
overflow: hidden;width: 728px;
opacity:0.4;
}

#site-title,
#site-description {
	margin:30;
	font-weight:300;
	float:left;
	line-height:75px;
}
/*
#wrapper {
	position:relative;
	max-width:1140px;	margin:0 auto;
	box-shadow:0 0 18px rgba(0, 0, 0, .4);
	overflow:hidden;
        /*opacity:0.4;
        filter:alpha(opacity=40);*/ /* For IE8 and earlier */
}

#wrapper {
	margin-top: 0px;

	padding: 0 0px;
}

#main {
        background: #fff;
}