header{
    position:fixed;
    width: 100%;
    min-width: 1200px;
    z-index:100;
}
header .bg{
    width: 100%;
    min-width: 1200px;
}
header .holder{
    position:absolute;
    width:100vw;
    height:85%;
    margin:auto;
    left:0;
    right:0;
}
header .holder .menu{
    position:absolute;
    height:50%;
    left:0;
    top: 50%;
    -ms-transform: translateY(-50%);
    transform: translateY(-50%);
    margin-left:5%;
}
header .holder .mobile_toggle{
    position:absolute;
    display:none;
    top: 50%;
    -ms-transform: translateY(-50%);
    transform: translateY(-50%);
    margin-left:30px;
    z-index:11;
}
header .holder .mobile_toggle div{
    width:35px;
    cursor:pointer;
}
header .mobile_menu{
    position:absolute;
    display:none;
    z-index:10;
    background:rgba(0,0,0,0.7);
    width:100%;
    height:100vh;
    text-align:center;
    padding-top:10%;
}
header .mobile_menu .link{
    height:20px;
    padding:10px;
    margin-bottom:10px;
}
header .holder .menu .link{
    display:inline-block;
    margin-right:40px;
    height:25%;
    top: 50%;
    -ms-transform: translateY(-50%);
    transform: translateY(-50%);
}
header .holder .logo{
    position:absolute;
    width:20%;
    margin:auto;
    margin-top:1%;
    left:0;
    right:0;
    z-index:11;
}
header .holder .download{
    position:absolute;
    height:50%;
    top: 50%;
    -ms-transform: translateY(-50%);
    transform: translateY(-50%);
    right:0;
    margin-right:5%;
    z-index:11;
}
header .holder .download .title{
    display:inline-block;
    margin:0 20px;
    height:25%;
    vertical-align:middle;
}
header .holder .download .link{
    display:inline-block;
    margin-left:10px;
    height:100%;
    vertical-align:middle;
}
@media screen and (max-width: 1200px) {
    header{
        left: 50%;
        margin-left: -600px;   /* 50% */
    }
    header .holder .logo{
        width:240px;
        margin-top:15px;
    }
    header .holder .menu{
        margin-left:20px;
    }
    header .holder .menu .link{
        margin-right:20px;
    }
    header .holder .download{
        margin-right:20px;
    }
    header .holder .download .title{
        margin:0 10px;
    }
}
@media screen and (max-width: 1000px) {
    header .holder .menu{
        display:none;
    }
    header .holder .mobile_toggle{
        display:block;
    }
    header .holder .mobile_toggle .open{
        display:block;
    }
    header .holder .mobile_toggle .close{
        display:none;
    }
}
@media screen and (max-width: 768px) {
    header{
        min-width: 500px;
        left: 0;
        margin-left: 0px;
    }
    header .bg{
        min-width: 500px;
    }
    header .holder .logo{
        width:35%;
        margin-top:2%;
    }
    header .holder .mobile_toggle{
        margin-left:3%;
    }
    header .holder .download{
        height:70%;
        margin-right:3%;
    }
    header .holder .download .title{
        display:none;
    }
    header .mobile_menu{
        padding-top:20%;
    }
}
@media screen and (max-width: 500px) {
    header{
        left: 50%;
        margin-left: -250px;   /* 50% */
    }
    header .holder .logo{
        width:160px;
        margin-top:10px;
    }
}