body {
    background-color: #f1f1f1;
}

#mainFrame {
    background-color: #555555;
    width: 90%;
    height: 200px;
    margin: 5px;
    padding: 0;
    border: 2px solid #000;
    resize: both; /* Allows resizing both horizontally and vertically */
    overflow: hidden; /* Prevent content from overflowing while resizing */
    background-size: cover;
    background-repeat: no-repeat;
}