.header {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: flex-start;
    position: fixed;
    top: 0;
    width: 100%;
    padding: 16px 30px;
    z-index: 500;
    transition: width background-color .2s;
    background-color: #fff;
    border-bottom: 1px solid rgba(130,126,126,.2);
    box-shadow: 5px 1px 15px rgba(0,0,0,.15);
}

#windy-api-logo {
    background-image: url(https://api.windy.com/static/img/api-logo-gray.svg);
    background-size: contain;
    background-repeat: no-repeat;
    background-position: left center;
    text-decoration: none;
    flex-basis: 150px;
    width: 150px;
    height: 50px;
    display: inline-block;
    vertical-align: middle;
    margin-right: 1em;
    position: relative;
    top: -0.1em;
    z-index: 10;
}

.header .nav {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    flex: 1;
    align-self: center;
    transition: transform .2s ease-in-out;
}

.header .menu {
    padding: 0;
    margin: 0;
    align-self: center;
}

.header li {
    list-style: none;
    display: inline-block;
}

#menu-active{
    font-weight: 500;
}

.menu-item {
    font-size: 18px;
    color: #6d7278;
    font-weight: 100;
    text-decoration: none;
    padding: 0 0.5em;
}

.header .button {
    display: inline-block;
    padding: 8px 15px;
    text-decoration: none!important;
    cursor: pointer;
    border-radius: 8px;
}

.header .button {
    font-weight: 100;
    border: 1px solid #4a4a4a;
    color: #4a4a4a;
}

#burger {
    display: none;
    background: url(https://api.windy.com/static/img/burger-gray.svg) no-repeat;
    background-size: cover;
    width: 29px;
    height: 25px;
    float: right;
    z-index: 10;
    align-self: center;
}

@media only screen and (max-width: 767px) {

    .header {
        padding: 8px 10px;
    }

    #burger {
        display: block;
    }

    .header.open #burger {
        background-image: none;
        position: relative;
        top: -3px;
    }

    .header.open #burger:after,
    .header.open #burger:before {
        position: absolute;
        left: 15px;
        content: ' ';
        height: 33px;
        width: 4px;
        background-color: #666;
    }

    .header.open #burger:before {
        transform: rotate(45deg); 
    }

    .header.open #burger:after {
        transform: rotate(-45deg);  
    }

    .header .nav {
        transform: translateX(100%);
        display: flex;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background-color: #fff;
        text-align: center;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    }

    .header.open .nav {
        transform: translateX(0);
    }

    .header .nav li {
        display: block;
        padding: 0.7em 0;
    }

    .menu-item {
        font-size: 1.25em;
    }

    .header .button {
        margin-top: 4em;
        color: #6d7278;
        border-color: #6d7278;
        padding: 5px 10px;
        font-size: .9em;
    }
}