.main-menu {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-flex-flow: column nowrap;
    -ms-flex-flow: column nowrap;
    flex-flow: column nowrap;
    list-style: none;
    position: absolute;
    top: 48px;
    left: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    transition: opacity .3s ease-in-out;
    opacity: 0;
    overflow: hidden;
    z-index: 100;
    pointer-events: none;
}

.main-menu.is-open {
    opacity: 1;
    pointer-events: auto;
    overflow-y: auto;
}

/* Main Menu Link */
.main-menu__link > button,
.main-menu__link > a{
    padding-left: 10px;
    text-align: left;
    width: 100%;
}

/* Sub menu */
.main-sub-menu {
    transition: opacity .2s ease-in-out;
    height: 0;
    opacity: 0;
    overflow: hidden;
    pointer-events: none;
}

.main-sub-menu__container {
    padding-top : 20px;
    padding-bottom : 20px;
}

.main-sub-menu__grid {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-orient: vertical;
    -webkit-box-direction: normal;
    -webkit-flex-direction: column;
    -ms-flex-direction: column;
    flex-direction: column;
    list-style: none;
}

.main-menu__link.is-open .main-sub-menu {
    height: auto;
    opacity: 1;
    z-index: 101;
    pointer-events: auto;
}

.sub-menu__link {
    margin-left : auto;
    margin-right : auto;
    text-align: center;
}

.sub-menu__link a{
    display: block;
}

/* thumbmail */
.sub-menu__thumbmail {
    height: 218px;
    width: 218px;
    overflow: hidden;
}


@media (min-width: 768px) {
    .main-menu-block {
        -webkit-box-flex: 1;
        -webkit-flex-grow: 1;
        -ms-flex-positive: 1;
        flex-grow: 1;
    }

    button.mobile-menu {
        display: none;
    }

    .main-menu {
        display: -webkit-inline-box;
        display: -webkit-inline-flex;
        display: -ms-inline-flexbox;
        display: inline-flex;
        -webkit-flex-flow: row nowrap;
        -ms-flex-flow: row nowrap;
        flex-flow: row nowrap;
        -webkit-justify-content: space-around;
        -ms-flex-pack: distribute;
        justify-content: space-around;
        position: static;
        opacity: 1;
        pointer-events: auto;
    }

    /* Main menu link */
    .main-menu__link button,
    .main-menu__link a{
        padding-left: 0;
        width: auto;
    }

    .main-sub-menu {
        position: absolute;
        top: 48px;
        left: 0;
        right: 0;
        bottom: 0;
        overflow-y: auto;
        height: auto;
        z-index: 100;
        transition-duration: .3s;
    }

    .main-sub-menu__grid {
        -webkit-flex-flow: row wrap;
        -ms-flex-flow: row wrap;
        flex-flow: row wrap;
        -webkit-box-pack: center;
        -webkit-justify-content: center;
        -ms-flex-pack: center;
        justify-content: center;
    }

    .sub-menu__link {
        margin: 0;
        padding: 10px 5px;
    }
}