index.css

body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f0f0f0;
}

.container {
    display: flex;
    height: 100vh;
}

.sidebar {
    width: 200px;
    background-color: #36393f;
    color: #fff;
    padding: 20px;
}

.sidebar h1 {
    font-size: 18px;
}

.sidebar ul {
    list-style-type: none;
    padding: 0;
}

.sidebar li {
    margin-bottom: 10px;
    cursor: pointer;
}

.chat {
    flex: 1;
    background-color: #fff;
    border-left: 1px solid #ccc;
    display: flex;
    flex-direction: column;
}

.chat-header {
    background-color: #36393f;
    color: #fff;
    padding: 10px;
}

.chat-header h2 {
    margin: 0;
    font-size: 16px;
}

.messages {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
}

.message {
    margin-bottom: 10px;
}

.user {
    font-weight: bold;
}

.input-box {
    padding: 20px;
    display: flex;
}

.input-box input {
    flex: 1;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 14px;
}

.input-box button {
    padding: 10px 20px;
    background-color: #36393f;
    color: #fff;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    margin-left: 10px;
    font-size: 14px;
}

.input-box button:hover {
    background-color: #555;
}