Here is a list of classes of the chatbot elements. If I missed anything or any questions come up, please let me know. I’ll be happy to help 
.es-window-container - chat window container
.es-window-header - header of the chat window
.es-avatar-container - avatar container
.es-avatar-background - avatar background
[class*="window-header__Title-sc"] - agent profile name
[class*="window-header__Caption-sc"] - agent profile caption
.es-header-button-new-chat - New Chat button
.es-header-button-transcript - Save Transcript button
.es-message-user - message of the user
.es-message-assistant - bot messages
.es-message-background - message background
.es-quick-reply-button - quick reply button
.es-form-field-shortText - Short Text field of the form
.es-form-field-email - Email field of the form
.es-form-field-phone - Phone field of the form
.es-choice-option-item-label - Consent field label
.es-button-base-container - container of the Submit button in the form
.es-button-base-ellipsis - text of the Submit button in the form
.es-window-footer - footer of the chat window
.es-window-footer-content - footer content of the chat window
.es-interaction-field-container - message input container
[class*="TextControlBase__TextControlBasePlaceholder-sc"] - message input placeholder
.es-interaction-field-submit-button - Send Message button
[class*="footer__FooterText-sc"] - footer text
.es-footer-action-restart-button - Start New Conversation button