#cluster-map {
    width: 100%;
    height: 500px;
} 

#map {
    width: 100%;
    height: 300px;
}
#offline-message {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1050; /* Higher than most elements */
    text-align: center;
    padding: 10px;
    font-weight: bold;
    background-color: red; /* Make it more visible */
    color: white;
}