body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: #f4f6f8;
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.chat-container {
    width: 95%;
    max-width: 700px;
    height: 90vh;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.chat-header {
    background: #4a90e2;
    color: white;
    padding: 15px 20px;
    text-align: center;
    font-size: 1.1rem;
}

.chat-box {
    flex-grow: 1;
    padding: 20px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.message {
    padding: 12px 18px;
    border-radius: 20px;
    line-height: 1.5;
    max-width: 80%;
    word-wrap: break-word;
}

.message.user {
    background-color: #4a90e2;
    color: white;
    align-self: flex-end;
    border-bottom-right-radius: 5px;
}

.message.bot {
    background-color: #e9ecef;
    color: #333;
    align-self: flex-start;
    border-bottom-left-radius: 5px;
}

.message.loading {
    color: #888;
    font-style: italic;
}

.chat-input {
    display: flex;
    padding: 20px;
    border-top: 1px solid #ddd;
}

#user-input {
    flex-grow: 1;
    border: 1px solid #ccc;
    border-radius: 25px;
    padding: 12px 20px;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

#user-input:focus {
    border-color: #4a90e2;
}

#send-btn {
    background-color: #4a90e2;
    color: white;
    border: none;
    border-radius: 25px;
    padding: 12px 25px;
    margin-left: 10px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: bold;
    transition: background-color 0.2s;
}

#send-btn:hover {
    background-color: #357abd;
}