.header { height: 40px; position: fixed; z-index: 50; top: 0; width: 100%; } 
//.logo { float: left; }
.nav { float: left; margin-left: 40px;margin-top: 20px;}
.nav a { text-decoration: none; color: #000; font-size: 2.5rem; }
.nav > div { float: left; text-align: center; padding: 5px; background: rgba(0,0,0,0.4); font-size: 20px; width: 35px; }
.nav > div div { display: none; }
.nav > div:hover div { display: block; }
.nav span { display: block; }

.nav .social { float: right; width: auto; padding-left: 20px; padding-top: 8px;}
.nav .social a { display: inline-block; padding: 0px 5px }

.social img { height: 34px; }