body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #1e1e1e;
    color: #dcdcdc;
    margin: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    overflow: hidden;
}

.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px 30px;
    background: #333333;
    color: #ffffff;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.3);
    box-sizing: border-box;
}

.logo img {
    height: 50px;
    width: auto;
}

.headbar {
    display: flex;
    align-items: center;
    gap: 20px;
    flex-grow: 1;
    justify-content: center;
}

.headbar a {
    color: #ffffff;
    text-decoration: none;
    font-size: 16px;
    font-weight: bold;
    padding: 10px;
    transition: color 0.3s ease;
    display: block;
}

.headbar a:hover {
    color: #00aaff;
}

.menubtn {
    display: none;
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: #ffffff;
    border-radius: 5px;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

@media (max-width: 768px) {
    .headbar {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 60px;
        right: 0;
        background: #333333;
        width: 100%;
        border-top: 1px solid #444444;
        box-sizing: border-box;
    }

    .headbar.show {
        display: flex;
    }

    .headbar a {
        padding: 15px;
        text-align: center;
        border-bottom: 1px solid #444444;
        width: 100%;
    }

    .menubtn {
        display: block;
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
}

.container {
    width: 90%;
    max-width: 800px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
    border-radius: 10px;
    background: #2b2b2b;
    padding: 0;
    margin-top: 80px;
}

.chatbox {
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    height: 500px;
    overflow: hidden;
    background: #333333;
    background-image: radial-gradient(circle, #444444, #333333);
    transition: box-shadow 0.3s ease-in-out;
    margin: auto;
}

.chatbox-header {
    background: #444444;
    color: #ffffff;
    padding: 16px;
    text-align: center;
    font-size: 22px;
    font-weight: bold;
    border-bottom: 1px solid #555555;
}

.chatbox-body {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
    background: #2b2b2b;
    position: relative;
}

.chatbox-footer {
    display: flex;
    padding: 12px;
    border-top: 1px solid #555555;
    background: #444444;
}

#user-input {
    flex: 1;
    padding: 12px;
    border: 1px solid #555555;
    border-radius: 8px;
    background: #1e1e1e;
    color: #ffffff;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.3);
    transition: box-shadow 0.3s ease-in-out, border-color 0.3s ease;
}

#user-input:focus {
    box-shadow: inset 0 4px 6px rgba(0, 0, 0, 0.5), 0 0 8px rgba(0, 186, 255, 0.7);
    border-color: #0d6efd;
    outline: none;
}

#send-button {
    padding: 12px 18px;
    border: none;
    background: linear-gradient(135deg, #0d6efd, #0a58ca);
    color: #ffffff;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
    font-weight: bold;
    transition: background 0.3s ease, transform 0.3s ease;
}

#send-button:hover {
    background: linear-gradient(135deg, #0a58ca, #004085);
    transform: scale(1.05);
}

.message {
    margin-bottom: 12px;
    padding: 12px;
    border-radius: 8px;
    max-width: 80%;
    line-height: 1.5;
    word-wrap: break-word;
    transition: background-color 0.3s ease;
}

.message.user-message {
    background-color: #0d6efd;
    color: #ffffff;
    align-self: flex-end;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}

.message.bot-message {
    background-color: #444444;
    color: #dcdcdc;
    align-self: flex-start;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}

@media (max-width: 768px) {
    .container {
        width: 100%;
        margin: 0;
        margin-top: 80px;
    }
    
    .chatbox {
        height: 80vh;
    }
}