Adapt Header to match Website

hi, i’ve been playing with the CSS file to match the header with the one of the website (www.mothersguidetoclimatechange.org/test/index.html)

the blog is https://www.mothersguidetoclimatechange.org/blog/

So what I would like is to get the following header:

<div id=”header”>
<div id=”headertop”>
</div>
<div id=”headernav”>

• CONTACT
• |
• LINKS
• |
• KATY’S BLOG
• |
• GAIL’S BLOG
• |
• THE BOOK
• |

<li class=”navactive”>HOME

</div>
<div id=”headerphoto”>
</div>
</div>

CSS being:

#header {
margin: 20px 0 0 0;
}
#headertop {
height: 150px;
background-image: url(images/GenerationClimate-Heading.png);
}
#headernav {
height: 40px;
}
#headernav ul {
list-style: none;
padding: 0;
margin: 0;
}
#headernav li {
float: right;
margin: 5px 5px;
}
#headernav li a {
text-decoration:none;
font-size: 14px;
color: #595959;
font-family: Verdana, Geneva, sans-serif;
}
#headernav li a:hover {
text-decoration:none;
font-size: 14px;
color: #376092;
font-family: Verdana, Geneva, sans-serif;
}
#headernav .navactive a, .navactive a:hover {
text-decoration:none;
font-size: 14px;
color: #376092;
font-family: Verdana, Geneva, sans-serif;
font-weight: bold;
}
#headerphoto {
height: 200px;
background-image: url(images/Header-Photo.png);
border-color: #bfbfbf;
border-width: 1px 1px 1px 1px;
border-style: solid;
}

I use the default wordpress file. I already managed to adapt length and everything, except the split up of the header images and the menu (ul li). can you help me with this please??? i can’t figure it out. i tried to insert a new div, also in the header.php but it does not show up, just blows up the whole page…

here’s my blog’s CSS:

/*
Theme name: WordPress Default – kubrick –
Editors: Navid Kashani
Persian WordPress Project : wp-persian.com
*/
body, .commentlist li, #commentform input, #commentform textarea, #commentform p, #sidebar, #wp-calendar caption {
font-family:tahoma, arial;
}
#page {
text-align:right;
direction:rtl;
}
h1, h2, h3, #sidebar h2 {
font-family:arial, tahoma;
}
.commentlist li .avatar {
float:left;
}

.commentlist li {
padding: 5px 10px 10px 5px;
}
.commentlist li ul li {
margin-left: -5px;
margin-right: 10px;
}

.commentlist p {
margin: 10px 0 10px 5px;
}
#header {
margin:0 1px 0 0;
}
.narrowcolumn {
float:right;
padding: 0 45px 20px 0;
}
.widecolumn {
margin: 5px 150px 0 0;
}
.widecolumn .smallattachment {
margin: 5px 0 5px 5px;
}
.postmetadata {
clear:right;
}
#sidebar {
margin-left: 0;
margin-right: 545px;
}
img.alignright {
margin: 0 7px 2px 0;
}

img.alignleft {
margin: 0 0 2px 7px;
}

.alignright {
float: left;
}

.alignleft {
float: right;
}
code {
display:block;
direction:ltr;
text-align:left;
}
acronym, abbr, span.caps {
letter-spacing:0; /* fix opera bug */
}
html>body .entry ul {
padding:0 10px 0 0;
text-indent:10px;
}
html>body .entry li {
margin: 7px 10px 8px 0;
}
.entry ol {
padding: 0 35px 0 0;
}
#sidebar ul ul, #sidebar ul ol {
margin: 5px 10px 0 0;
}
#sidebar ul ul ul, #sidebar ul ol {
margin: 0 10px 0 0;
}
#commentform {
margin: 5px 0 0 10px;
}
#commentform input {
margin: 5px 0 1px 5px;
}
#commentform #submit {
float:left;
}
.commentlist p {
margin: 10px 0 10px 5px;
}

.children .even, .alt {
border-left: 0;
border-right: 1px solid #ddd;
}

#wp-calendar #next a {
padding-right:0;
padding-left:10px;
text-align:left;
}
#wp-calendar #prev a {
padding-left:0;
padding-right:10px;
text-align:right;
}
blockquote {
margin: 15px 10px 0 30px;
padding-left: 0;
padding-right: 20px;
border-left: 0 none;
border-right: 5px solid #ddd;
}
#email, #url {
direction:ltr;
}