(CSS stylesheet) 2 problems

version is 3.7.3

Hi,

I have a problem with my website… I want first of all, to put the header (the big logo on top of my website to not take the full width of my website but to be in line with my articles)

Not even sure if it’s in the header.. but here is the coding

/* Headers */
h1, h2, h3, h4, h5, h6 {
color: #333;
margin: 0.5em 0;
padding: 0;
line-height: 1.1em;
}
h2.suf-mag-category-title {
margin: 0;
}
h1 a, h2 a, h3 a, h4 a, h5 a, h6 a {
color: #333;
}
h1, h2 {
font-weight: normal;
}
h3, h4, h5, h6 {
font-weight: bold;
}
h1 {
font-size: 200%;
}
h2 {
font-size: 183%;
}
h3 {
font-size: 166%;
}
h4 {
font-size: 150%;
font-weight: bold;
}
h5 {
font-size: 133%;
font-weight: bold;
}
h6 {
font-size: 116%;
font-weight: bold;
}

sup, sub {
height: 0;
line-height: 1;
vertical-align: baseline;
position: relative;
font-size: 0.7em;
}
sup {
bottom: 1ex;
}
sub {
top: .5ex;
}

/* WordPress Standard Elements */
img#wpstats {
width:0;
height:0;
overflow:hidden;
}

.border{
padding: 2.5px;
border: 1px solid #ccc;
}
.hidden {
display: none;
visibility: hidden;
}
.aligncenter {
display: block;
margin-left: auto;
margin-right: auto;
}
.alignleft {
float: left;
margin:0 10px 5px 0;
}
.alignright {
float: right;
margin:0 0 5px 10px;
}
.sticky, .bypostauthor {}

.floatleft{
float:left;
margin:3px 7px 0 0;
}
.floatright{
float:right;
margin:3px 0 0 7px;
}
.right{
float:right;
}
.block{
display:block;
}
.left{
float:left;
}
.clear{
clear:both;
}
.center {
text-align: center;
}
dl.gallery-item {margin:0}
div.suf-widget{
background: #fff;
border: 1px solid #c0c0c0;
}