body, html {
    margin: 0;
    padding: 0;
    height: 100%;
    width: 100%;
    overflow: hidden;
}
.container {
    display: flex;
    height: 100%;
}
#map {
    flex: 1;
    height: 100%;
}
#threejs {
    flex: 1;
    height: 100%;
    position: relative;
}
#download-btn {
    position: absolute;
    bottom: 20px;
    right: 20px;
    z-index: 1000;
    padding: 10px 15px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
}
#download-btn:hover {
    background-color: #45a049;
}