1) Please login wp-admin, go to Aside / Layout, activate “fixed sidebar”

2) Please login wp-admin, go to Aside / General Settings / Custom Css
Paste the style code to Custom Css:

#sidebar.sidebar_show {
    left: 0; 
    width: 100%;
    height: 80px;
}
#logo {
    width: 200px;
    line-height: 60px;
    max-height: 60px;
    padding-left: 60px;
    margin-top: 0;
    display: inline-block;
    float: left;
}
#logo a {
    margin-right: 0;
}
#logo img {
    max-height: 80px;
}
#navi {
    margin-top: 20px;     
display: inline-block;
    float: left;
}
#navi>div>ul>li>a { 
    min-width: auto;
}
.sidebar-bottom-wrap {
position: static;
max-width: none;
}
.sidebar-bottom-wrap .copyright{
display: none;
}
#search_form{
line-height: 80px;
}
#sidebar.sidebar_show ~ #main-wrap {
    padding-left: 0;
}