@keyframes blink{0%{opacity:1}50%{opacity:0}to{opacity:1}}.blink{animation:blink 1s infinite}#chat-center{position:fixed;bottom:20px;right:20px;width:300px;height:400px;background-color:#f0f0f0;border:1px solid #ccc;border-radius:5px;display:flex;flex-direction:column}#chat-messages{flex-grow:1;overflow-y:auto;padding:10px;display:flex;flex-direction:column}.message{max-width:80%;border-radius:10px;padding:10px;margin-bottom:10px}.received-message{align-self:flex-start;background-color:#dcf8c6}.sent-message{align-self:flex-end;background-color:#e5e5ea}.message-sender{font-weight:700;margin-right:5px}#chat-form{display:flex;align-items:center;padding:10px;background-color:#e0e0e0}#chat-input{flex-grow:1;padding:5px;border:1px solid #ccc;border-radius:3px}#chat-send{margin-left:10px;background-color:#4caf50;color:#fff;border:none;border-radius:3px;padding:5px 10px;cursor:pointer}#chat-send i{font-size:16px}#chat-send.sending{background-color:#ccc;cursor:not-allowed}#chat-send.sending i{display:none}.close-chat{position:absolute;right:10px;background:none;border:none;font-size:20px;cursor:pointer;top:-1px}