@media screen and (max-width: 320px) {  
    .nav { display: none; }
}

#masthead {
    height: 68px;
    background: #fff;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    width: 94.5%;
    z-index: 5;
    padding: 0 3% 14px;
    font-size: 1.5em;
    color: #989999;
    overflow: hidden;
    }

    #title {
        text-transform: uppercase;
        margin: 0;
        font-weight: normal;
        font-size: 1em;
        width: 95%;
        white-space: nowrap;
        overflow: hidden;
        }

        #title .chap, #title b {
            padding-top: 9px;
            padding-bottom: 11px;
            text-overflow: ellipsis;
            overflow: hidden;
            vertical-align: top;
            }

        #title b { 
            padding-left: 15px;
            margin-left: 10px;
            color: #4e5456;
            font-weight: bold;
            display: inline-block;
            }

            #title .chap-numb { margin-left: 0; }

            header .chap-name { 
                border-left: 3px solid #ececec; 
                max-width: 200px;
                }

        #open-index-link, .nav { 
            float: right;
            padding-top: 11px;
            padding-bottom: 11px;
            text-transform: uppercase;
            font-weight: bold;
            font-size: .8em;
            }

        #open-index-link {
            padding-right: 20px;
            margin-left: 13px;
            background: url(../img/icon_menu.svg) center right no-repeat;
            }

        .nav-wrapper {
            width: 87px;
            white-space: nowrap;
            float: right;
            }

            .nav {  
                z-index: 5;
                background-repeat: no-repeat;
                background-position: left 60%;
                background-size: 15px 15px;
                width: 30px;
                height: 15px;
                float: none;
                display: inline-block;                
                -webkit-transition: width .2s ease;
                        transition: width .2s ease;   
                }

                .nav span { display: none; }

     .nav.inactive { opacity: .3; }

     .nav.active:hover, .nav.active:focus,
     .prev.active:hover, .prev.active:focus { opacity: .8; }

        .next {
            border-left: 3px solid #ececec;
            background-image: url(../img/nav_arrow_right.svg);
            background-position: right 60%;
            }

            .next span { 
                margin-right: 30px; 
                margin-left: 30px; 
                }

        .prev { 
            background-image: url(../img/nav_arrow_left.svg); 
            padding-right: 0;
            }

            .prev span { 
                margin-left: 30px; 
                margin-right: 30px; 
                }


@media screen and (min-width: 768px) {     
  
    /* MASTHEAD */
    #masthead { 
        height: 35px; 
        position: fixed;
        }

        #masthead nav { 
            float: right;
            width: 52%;
            }

        #title { 
            width: 48%; 
            float: left;
            }

    .nav-wrapper { float: right; }

        .nav { 
            background-size: 20px 20px;
            height: 21px;
            }

    #open-index-link, .nav { 
        font-size: 1em; 
        line-height: 1.1em;
        padding-bottom: 17px;
        }

    #open-index-link { 
        margin-left: 45px; 
        padding-bottom: 10px;
        }

    header .chap-numb { border-left: 3px solid #ececec; }

 } /* /768 */

 @media screen and (min-width: 1024px) {

    #masthead nav { width: 40%; }

    #title { width: 60%; }

    header .chap-name { max-width: 310px; }

 } /* / 1024 */

@media screen and (min-width: 1200px) {

    header .chap-name { max-width: 550px; }

    .nav-wrapper { width: 262px; }

        .nav { }

            .nav span { 
                height: auto;
                overflow: hidden;
                text-overflow: ellipsis;
                white-space: nowrap;
                display: block;
                visibility: hidden; 
                -webkit-transition: visibility .5s ease;
                        transition: visibility .5s ease;  
                }

        .nav.open { 
            width: 221px;
            -webkit-transition: width .2s ease;
                    transition: width .2s ease;   
            }

            .nav.open span { 
                visibility: visible; 
                -webkit-transition: visibility .2s ease;
                        transition: visibility .2s ease;  
                }
}