body {
    color: #000F2D;
    font-family: 'Roboto', sans-serif;
    font-size: 1em;
    line-height: 1.35;
    background: -webkit-linear-gradient(white 55%, #0040FF 95%);
    background: linear-gradient(white 55%, #0040FF 95%);
}

h1, h2, h3, h4 {
    font-family: 'Roboto', sans-serif;
}

span.spambescherming {
    display: none;
}

header {
    background-image: url(../afbeeldingen/header.JPG);
    background-size: 100% auto;
    background-repeat: no-repeat;
    padding: 4em 0;
    text-align: center;
}

header a {
    text-decoration: none;
    color: #00FE00;
    text-shadow: 2px 2px 1px grey;
    letter-spacing: .03em;
    font-size: 1em;
}

nav {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    display: block;
}

nav p.menuknop {
    font-family: courier, monospace;
    font-size: 35px;
    margin: 0 4px 0 0;
    text-align: right;
    display: inline-block;
    cursor: pointer;
    float: right;
}

.onder, .midden, .boven {
    width: 35px;
    height: 5px;
    background-color: blue;
    margin: 6px 0;
    transition: 0.5s;
}

.change .onder {
  -webkit-transform: rotate(-45deg) translate(-9px, 6px);
  transform: rotate(-45deg) translate(-9px, 6px);
}

.change .midden {opacity: 0;}

.change .boven {
  -webkit-transform: rotate(45deg) translate(-8px, -8px);
  transform: rotate(45deg) translate(-8px, -8px);
}

nav ul {
    background-color: #0040FF;
    display: none;
    list-style-type: none;
    padding: 0;
    margin: 0;
}

nav ul li {
    border-top: 0px solid darkgrey;
    padding: 0.6em 0.5em 0.6em 0.5em;
}

nav a {
    color: white;
    text-decoration: none;
}

nav ul li a {
    display: block;
}

nav ul li:hover {
    background-color: #FF001A;
}

nav ul li.submenu {
    position: relative;
}

nav ul li a:hover {
    color: #00FE00;
}

nav ul li.submenu > a:after {
    content: " \025BE";
}

nav ul li.submenu:hover ul {
    box-sizing: border-box;
    background-color: #0040FF;
    display: block;
    width: 50%;
    position: absolute;
    top: 0;
    left: 50%;
    z-index: 2;
}

nav li li:first-child {
    border-top: none;
}

nav li li a:hover {
    color:  #00FE00;
}

div.art-aside {
    width: 90%;
    margin: -40px auto 0 auto;
    background-color: white;
    box-shadow: 0 0 10px #444;
    border-radius: 4px;
}

article {
    padding: 2em;
    min-height: 300px;
}

article h1 {
    color: #000F2D;
    font-size: 1.6em;
}

article h2 {
    color: #000F2D;
    font-size: 1.4em;
}

article h3 {
    color: #000F2D;
    font-size: 1.2em;
}

aside {
    padding: 1em 1em 2em 1em;
    text-align: center;
    border-bottom-left-radius: 4px;
    border-bottom-right-radius: 4px;
}

aside h3, aside h4 {
    color: #000F2D;
}

footer {
    color: white;
    font-size: 0.9em;
    padding: 2em;
    text-align: center;
    margin: 0;
}

footer a {
    color: white;
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

img.rechts, img.links {
    box-sizing: border-box;
    display: block;
    margin: 0.5em auto;
    max-width: 100%;
}

@media screen and (max-width: 499px) {
    nav a {
        color: #0040FF;
        text-decoration: none;
        }
    nav ul li {
        background-color: lightgray;
    }
    nav ul li:hover {
        background-color: darkgrey;
    }
    nav ul li.submenu > a:after {
    content: " \025B8";
    }
}

@media screen and (min-width: 500px) {
    header {
        padding: 6em 0.5em;
    }
    div.nav-aa {
        box-shadow: 0 0 5px #444;
        border-radius: 4px;
        width 90%;
        margin: -100px auto 0 auto;
        background-color: white;
    }
    nav {
        position: relative;
        border-top-left-radius: 4px;
        border-top-right-radius: 4px;
    }
    nav p.menuknop {
        display: none;
    }
    nav > ul > li:first-child {
         border-top-left-radius: 4px;
    }
    nav > ul > li:last-child {
        border-top-right-radius: 4px;
    }  
    nav > ul {
        display: -webkit-box !important;
        display: -ms-flexbox !important;
        display: flex !important;
        -ms-flex-pack: distribute;
        justify-content: space-around;
        border-top-left-radius: 4px;
        border-top-right-radius: 4px;
    }
    nav ul li.submenu:hover ul {
        width: 8em;
        left: 0;
        top: 100%;
        -webkit-box-orient: vertical;
        -webkit-box-direction: normal;
        -ms-flex-direction: column;
        flex-direction: column;
        border-top: 1px solid darkgrey;
    }
    nav > ul > li {
        border-top: none;
    }
    div.art-aside {
        width: 100%;
        border: none;
        box-shadow: none;
        margin: 0;
    }
    img.rechts {
        float: right;
        margin: 0.4em 0 0.4em 1.2em;
        box-shadow: 3px 3px 3px #444;
    }
    img.links {
        float: left;
        margin: 0.4em 1.2em 0.4em 0;
        box-shadow: 3px 3px 3px #444;
    }
}

@media screen and (min-width: 700px) {
    .flex-container {
        display: flex;
        flex-direction: row;
    }    
    .flex-container > div {
        background-color: white;
        width: 50%;
        margin: 5px;
        text-align: left;
        padding: 10px 10px; 
        flex: 1;
    } 
    .flex-container img {
        box-shadow: 3px 3px 3px #444;
    }
    .art-aside {
        display: -webkit-box;
        display: -ms-flexbox;
        display: flex;
    }
    aside {
        -webkit-box-flex: 0;
        -ms-flex: 0 0 17%;
        flex: 0 0 17%;
        font-size: .9em;
        margin-top: 1em;
    }
}

@media screen and (max-width: 699px) {
    .flex-container {
        flex-direction: column;
    }
}

@media screen and (min-width: 1200px) {
    div.nav-aa {150px auto 0 auto;
        margin: -90px auto 0 auto;
    }    
    header {
        padding: 6em 0.5em;
    }
    header h1 {
        font-size: 4em;
    }
    div.nav-aa {
        max-width: 1150px;
    }
    nav > ul {
        -webkit-box-pack: center;
        -ms-flex-pack: center;
        justify-content: center;
    }
    nav > ul > li {
        margin: 0 .7em;
    }
}