body {
    margin: 0;
    display: flex;
    flex-direction: column;
    height: 100vh;
}
#header {
    padding: 10px;
    background-color: #f5f5f5;
    border-bottom: 1px solid #ccc;
}
#content {
    display: flex;
    flex: 1;
    height: calc(100% - 50px);
}
#tree {
    width: 30%;
    border-right: 1px solid #ccc;
    overflow-y: auto;
    padding: 10px;
}
#files {
    flex: 1;
    padding: 10px;
    overflow-y: auto;
}
ul {
    list-style-type: none;
    padding-left: 20px;
}
li {
    margin-bottom: 5px;
}
a {
    text-decoration: none;
    color: #007BFF;
}
a:hover {
    text-decoration: underline;
}