:root {
    --chat-bg: #f8f9fa;
    --border-color: #dee2e6;
    --card-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.1);
    --bubble-shadow: 0 2px 4px rgba(0, 0, 0, 0.075);
}

.co-author-container {
    max-width: 800px;
    margin: auto;
}

.chat-card {
    border: none;
    border-radius: 0.75rem;
    box-shadow: var(--card-shadow);
    overflow: hidden;
}

.chat-header {
    background-color: #0d6efd;
    color: white;
    padding: 1rem 1.5rem;
    text-align: center;
}

    .chat-header h2 {
        font-size: 1.5rem;
        margin-bottom: 0.25rem;
    }

    .chat-header p {
        opacity: 0.9;
    }

.chat-messages {
    background-color: var(--chat-bg);
    padding: 1.5rem;
    max-height: 60vh;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
  /*  gap: 1rem;*/
}

.message-bubble {
    width: fit-content;
    max-width: 80%;
    padding: 0.75rem 1.25rem;
    border-radius: 0.75rem;
    word-wrap: break-word;
    box-shadow: var(--bubble-shadow);
    position: relative;
}

    .message-bubble .sender-info {
        font-weight: bold;
        font-size: 0.8rem;
       /* margin-bottom: 0.25rem;*/
        opacity: 0.8;
    }

    .message-bubble .timestamp {
        font-size: 0.75rem;
        opacity: 0.6;
        margin-left: 0.5rem;
    }

.human-message {
    align-self: flex-end;
    background-color: #fff;
    border: 1px solid #0d6efd;
    color: #0d6efd;
}

.ai-message {
    align-self: flex-start;
    background-color: #f1f3f5;
}

.chat-footer {
    padding: 1rem 1.5rem;
    background-color: #fff;
    border-top: 1px solid var(--border-color);
}

.chat-input-group {
    display: flex;
    gap: 0.75rem;
    align-items: flex-end;
}

.auto-expand-textarea {
    resize: none;
    overflow-y: hidden;
    min-height: 48px;
    max-height: 200px;
    line-height: 1.5;
}

.form-control-setup {
    min-height: 52px;
}