.container {
    display: flex;
}

aside.toc {
    position: fixed;
    left: 0;
    top: 0;
    width: 250px; /* Adjust the width as needed */
    height: 100%;
    background-color: #f4f4f4; /* Optional: background color */
    padding: 20px; /* Optional: padding */
    box-shadow: 2px 0 5px rgba(0,0,0,0.1); /* Optional: shadow effect */
}

main.content {
    margin-left: 250px; /* Same as the width of the aside */
    padding: 20px; /* Optional: padding */
    flex-grow: 1;
}