body, html {
    height: 100%;
    margin: 0;
    overflow: hidden; /* Verhindert äußere Scrollbars */

body {
    background-image: url('../images/hintergruende/1x1-dunkelblau2.gif');
    margin: 0;
}

.container {
    display: flex;
    height: 100vh;
    max-width: 100%;
}

.nav-iframe {
    width: 15%;
    max-width: 212px;
    min-width: 212px;
    height: 100%;
    border: none;
}

.content-iframe {
    flex: 1;
    height: 100%;
    border: none;
}