.sm-main-menu-container {
    position: fixed;
    z-index: 100;
    left: 0px;
    right: 0px;
    top: 0px;
    background: #fff;
    box-shadow: 0px 0px 50px #888;
}    
.sm-menu:after {
    clear: both;
    content: "\00a0";
    display: block;
    height: 0;
    font: 0px/0 serif;
    overflow: hidden;
}

.sm-menu-white {

}
.sm-menu-white .nav-brand {
    /*position: absolute;
    top: 10px;*/

}

.sm-menu-white .main-menu-btn {
    float: right;
    margin: 19px 0px;
    position: relative;
    display: inline-block;
    width: 29px;
    height: 29px;
    text-indent: 29px;
    white-space: nowrap;
    overflow: hidden;
    cursor: pointer;
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
  }
  
  
/* hamburger icon */
  
.sm-menu-white .main-menu-btn-icon,
.sm-menu-white .main-menu-btn-icon:before,
.sm-menu-white .main-menu-btn-icon:after {
    position: absolute;
    top: 50%;
    left: 2px;
    height: 2px;
    width: 24px;
    background: #000;
    -webkit-transition: all 0.25s;
    transition: all 0.25s;
}
  
.sm-menu-white .main-menu-btn-icon:before {
    content: '';
    top: -7px;
    left: 0;
}
  
.sm-menu-white .main-menu-btn-icon:after {
    content: '';
    top: 7px;
    left: 0;
}
  
  
/* x icon */
  
.sm-menu-white .sm-menu-state:checked ~ .main-menu-btn .main-menu-btn-icon {
    height: 0;
    background: transparent;
}
  
.sm-menu-white .sm-menu-state:checked ~ .main-menu-btn .main-menu-btn-icon:before {
    top: 0;
    -webkit-transform: rotate(-45deg);
    transform: rotate(-45deg);
}
  
.sm-menu-white  .sm-menu-state:checked ~ .main-menu-btn .main-menu-btn-icon:after {
    top: 0;
    -webkit-transform: rotate(45deg);
    transform: rotate(45deg);
}
  
  
/* hide menu state checkbox (keep it visible to screen readers) */  
.sm-menu-white  .sm-menu-state {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    border: 0;
    padding: 0;
    overflow: hidden;
    clip: rect(1px, 1px, 1px, 1px);
}
  
  
/* hide the menu in mobile view */
.sm-menu-white .sm-menu-state:not(:checked) ~ .sm-white {
    display: none;
}
  
.sm-menu-white .sm-menu-state:checked ~ .sm-white {
    display: block;
}
  
@media (min-width: 768px) {
    /* hide the button in desktop view */
    .sm-menu-white .main-menu-btn {
        position: absolute;
        top: -99999px;
    }

    /* always show the menu in desktop view */
    .sm-menu-white .sm-menu-state:not(:checked) ~ .sm-white {
        display: block;
    }
}