html {
    box-sizing: border-box;
	min-width: 320px;
}

*, ::before, ::after {
    box-sizing: inherit;
}

body {
    margin: 10px auto;
    max-width: 60em;
    font-family: sans-serif;
    color: #333333;
    background-image: url("pics/grau.gif");
}

.header, .nav, .main, .article, .section, .aside, .footer {
    border-radius: 0.5em;
    border: 1px solid;
    padding: 10px;
    margin: 10px;
}

.header {
    background: rgb(152,152,152);
    border-color: rgb(102,102,102);
}

    .header img {
        display: none;
    }

    .header h1 {
        margin: 0 0 0 1em;
    }

.nav {
    font-size: 1em;
    padding: 0;
    background: rgb(204,204,204);
    border-color: rgb(102,102,102);
}

    .nav ul {
        padding: 0;
    }

    .nav li {
        list-style: none;
        margin: 0;
        padding: 0.5em 0.5em 0.5em 1em;
    }

    .nav a, .nav span {
        color: rgb(42,42,144);
    }

.main {
    display: block;
    /*background: grey;*/
    min-width: 16em; /* Mindestbreite (der Ueberschrift) verhindert Anzeigefehler in modernen Browsern */
    padding: 2px 0 0 0;
    border-style: none;
    margin: 10px 0 10px 0;
}

.article {
    background: rgb(204,204,204);
    border-color: rgb(102,102,102);
}

    .article .hadrei {
        font-weight: bold;
    }

.footer {
    background: rgb(152,152,152);
    border-color: rgb(102,102,102);
}

    .footer p {
        margin: 0px;
    }

    .footer #copyright {
        display: block;
    }

/* Link Dekoration */

.linksave:before {
    content: url(pics/save.gif);
    margin-right: 4px;
}

.linkext:before {
    content: url(pics/linkext.gif);
}

.linkint:before {
    content: url(pics/linkint.gif);
}

.weglassen {
    display: none;
}

/* Vorschau Bilder */

.prepic {
    position: relative;
    display: inline-block;
}

.prepic-content {
    display: none;
    position: absolute;
    top: 0px;
    left: 0px;
    background-color: #f9f9f9;
    min-width: 160px;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    z-index: 10;
}

.prepic:hover .prepic-content {
    display: block;
}

.prepic-desc {
    padding: 5px;
    text-align: center;
}

/* mehrspaltiges Layout für breitere Viewports */

@media (min-width: 500px) {
    .nav {
        float: left;
        width: 10em;
    }

    .header img {
        width: 64px;
        height: 64px;
        vertical-align: middle;
        margin-right: 2em;
        display: inline-block;
    }

    .main {
        margin-left: 11em;
    }

    .footer #copyright {
        float: right;
    }
}