header {
    background-color: #f8f9fa;
    padding: 1rem;
}

.container {
    margin-top: 1rem;
}

.sub-menu-parent {
    position: relative;
}

.sub-menu {
    visibility: hidden; /* hides sub-menu */
    opacity: 0;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    transform: translateY(-2em);
    z-index: -1;
    transition: all 0.1s ease-in-out 0s, visibility 0s linear 0.3s, z-index 0s linear 0.01s;
}

    .sub-menu li {
        background-color: #fff;
        width: 100%;
    }

.sub-menu-parent:focus .sub-menu,
.sub-menu-parent:focus-within .sub-menu,
.sub-menu-parent:hover .sub-menu {
    visibility: visible; /* shows sub-menu */
    opacity: 1;
    z-index: 1;
    transform: translateY(0%);
    transition-delay: 0s, 0s, 0.1s; /* this removes the transition delay so the menu will be visible while the other styles transition */
}

.error404 {
    width: 100%;
    float: left;
    display: block;
    height: 100%;
    position: fixed;
    text-align: center;
}

.button404 {
    border: 1px;
    background: #292c35;
    color: #fff;
    -webkit-border-radius: 3px;
    -moz-border-radius: 3px;
    border-radius: 3px;
    -webkit-transition: 200ms ease all;
    transition: 200ms ease all;
    -o-transition: 200ms ease all;
    -moz-transition: 200ms ease all;
    line-height: 16px;
    text-decoration: none;
    padding: 9px 30px;
    font-size: 13px;
    cursor: pointer;
    font-family: 'Open Sans', arial, sans-serif;
}

    .button404:hover {
        background: #0c0e12;
    }

.menu-header {  
    cursor: default;
}