/* General Reset */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    background-color: #111;
    color: #ccc;
    line-height: 1.6;
    margin: 0;
}

/* Header */
header {
    background-color: #222;
    color: #fff;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 20px;
}

header .logo {
    font-size: 1.5em;
    font-weight: bold;
}

header nav ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
}

header nav ul li {
    margin-left: 20px;
}

header nav ul li a {
    text-decoration: none;
    color: #ccc;
    transition: color 0.3s;
}

header nav ul li a:hover {
    color: #fff;
}

/* Main Layout */
main {
    display: flex;
    flex-wrap: wrap;
}

.sidebar {
    width: 20%;
    background-color: #1a1a1a;
    padding: 20px;
    min-height: 100vh;
}

.sidebar h3 {
    margin-bottom: 10px;
    font-size: 1.2em;
    color: #fff;
}

.sidebar ul {
    list-style: none;
}

.sidebar ul li a {
    text-decoration: none;
    color: #ccc;
    display: block;
    padding: 5px 0;
    transition: color 0.3s;
}

.sidebar ul li a:hover {
    color: #fff;
}

.content {
    flex: 1;
    padding: 20px;
    min-width: 300px;
}

.content h1 {
    margin-bottom: 20px;
    font-size: 2em;
    color: #fff;
}

.chat {
    margin-top: 20px;
    background-color: #222;
    padding: 10px;
    border-radius: 5px;
}

/* Chat Elements */
#chat-container {
    display: none; /* Initially hidden */
    margin-top: 50px;
    text-align: center;
}

#chat-box {
    height: 150px;
    background-color: #1a1a1a;
    padding: 10px;
    margin-bottom: 10px;
    overflow-y: auto;
    border: 1px solid #333;
    color: #fff;
    border-radius: 5px;
    box-sizing: border-box;
    text-align: left;
}

#chat-input {
    width: calc(100% - 80px);
    padding: 10px;
    background-color: #333;
    border: none;
    color: #fff;
    border-radius: 5px;
    margin-right: 10px;
}

#send-btn {
    width: 60px;
    background-color: #444;
    color: #fff;
    border: none;
    padding: 10px;
    cursor: pointer;
    transition: background 0.3s;
    border-radius: 5px;
}

#send-btn:hover {
    background-color: #555;
}

/* Registration Form */
#registration-container {
    display: block;
    text-align: center;
    margin-top: 50px;
}

#registration-container h2 {
    color: #fff;
}

#register-username,
#register-password,
#login-username,
#login-password {
    padding: 10px;
    background-color: #333;
    color: #fff;
    border: none;
    margin-bottom: 10px;
    border-radius: 5px;
    width: 200px;
}

#register-form button,
#login-form button {
    background-color: #444;
    color: #fff;
    border: none;
    padding: 10px;
    cursor: pointer;
    transition: background 0.3s;
}

#register-form button:hover,
#login-form button:hover {
    background-color: #555;
}

/* Error Messages */
#registration-error,
#login-error {
    display: none;
    color: red;
    margin-top: 10px;
    font-size: 1.2em;
    text-align: center;
}

/* Login Form */
#login-container {
    display: block;
    text-align: center;
    margin-top: 50px;
}

#login-container h2 {
    color: #fff;
}

/* Footer */
footer {
    background-color: #222;
    text-align: center;
    padding: 10px;
    color: #ccc;
}

#logout-btn {
    background-color: #444;
    color: #fff;
    border: none;
    padding: 10px 20px;
    cursor: pointer;
    transition: background 0.3s, color 0.3s;
    border-radius: 5px;
    font-size: 1em;
}

#logout-btn:hover {
    background-color: #555;
    color: #fff;
}

/* Responsive Design */
@media (max-width: 768px) {
    header {
        flex-direction: column;
        align-items: flex-start;
    }

    header nav ul {
        flex-direction: column;
        align-items: flex-start;
        padding-left: 0;
    }

    header nav ul li {
        margin-left: 0;
        margin-bottom: 10px;
    }

    .sidebar {
        width: 100%;
        min-height: auto;
        padding: 10px;
    }

    main {
        flex-direction: column;
    }

    .content {
        padding: 10px;
    }

    #chat-box {
        height: 200px;
    }

    #chat-input,
    #send-btn {
        width: 100%;
        margin-bottom: 10px;
    }

    #chat-input {
        margin-right: 0;
    }
}

@media (max-width: 480px) {
    header .logo {
        font-size: 1.2em;
    }

    .content h1 {
        font-size: 1.5em;
    }

    #register-username,
    #register-password,
    #login-username,
    #login-password {
        width: 90%;
    }
}