body {
    font-family: sans-serif;
    background: #f3f1d2;
    margin: 20px;
}
#container {
    display: flex;
    gap: 10px;
}
#tree {
    width: 200px;
    border: 1px solid #ccc;
    padding: 10px;
    background: #fff;
    overflow-y: auto;
    height: 400px;
}
textarea {
    width: 400px;
    height: 400px;
}
.selected {
    background: #bb8d76;
    color: white;
}