.nav-btn span{width:28px}.nav-btn span:before,.nav-btn span:after{width:20px}.nav-btn span:before{bottom:9px}.nav-btn span:after{top:7px}.nav-btn.active span:before{width:28px;-webkit-transform:rotate(-135deg);transform:rotate(-135deg)}.nav-btn.active span:after{width:28px;-webkit-transform:rotate(135deg);transform:rotate(135deg)}