html, body {
      font-family: 'Roboto', "Helvetica Neue", Helvetica, Arial, sans-serif !important;
    }

    body { background: #ece5dd; }
    .app-container { margin: 20px auto; max-width: 1000px; }
    .chat-header { display: flex; align-items: center; padding: 12px 16px; background: #075E54; color: #fff; border-top-left-radius: .25rem; border-top-right-radius: .25rem; }
    .chat-header img.avatar { width: 35px; height: 35px; border-radius: 50%; margin-right: 12px; }
    .chat-header .header-text h2 { margin: 0; font-size: 18px; font-weight: 500; }
    .chat-header .header-text p { margin: 0; font-size: 10px; opacity: 0.85; }
    .chat { padding: 16px; height: 500px; overflow-y: auto; background: #ffffff00 url('img/fondo.png') center bottom / contain repeat; margin-top: -1px; }
    .timestamp { text-align: center; font-size: 11px; color: #565656; margin: 8px 0; }
    .message { max-width: 80%; margin: 8px 0; padding: 10px 14px;
               border-radius: 18px; clear: both; word-wrap: break-word; position: relative;
               font-size: 14px; line-height: 1.4; display: inline-block; }
    .message .msg-time { display: block; text-align: right; margin-top: 4px; font-size: 10px; color: #555; }
    .Recibir { background: #dcf8c6; float: left; border-bottom-left-radius: 4px; border-bottom-right-radius: 18px; }
    .Enviar  { background: #ffffff; float: right; border-bottom-right-radius: 4px; border-bottom-left-radius: 18px; }
    .typing-indicator { background: #dcf8c6; float: left;border-bottom-left-radius: 4px; border-bottom-right-radius: 18px;display: inline-block; padding: 10px 14px; margin: 8px 0; }
    .typing-dots { font-size: 18px; letter-spacing: 4px; display: inline-block;animation: blink 1s steps(1,end) infinite; }
    @keyframes blink {
      0%, 20% { opacity: 0.2; }
      50%      { opacity: 1; }
      100%     { opacity: 0.2; }
    }
    .form-card { border-radius: .25rem; box-shadow: 0 2px 5px rgba(0,0,0,0.1); }
    .list-group-item { font-size: 14px; padding: 8px 12px; border: none; border-bottom: 1px solid #ddd; display: flex; justify-content: space-between; align-items: center; cursor: move; }
    .list-group-item:last-child { border-bottom: none; }
    #simulateBtn, #addBtn, #updateBtn { letter-spacing: .5px; }
    .typing-area { display: flex; align-items: center; margin-top: 0px; background: url('img/fondo.png') repeat; }
    .typing-area input { flex: 1; border-radius: 20px; padding: 8px 12px; border: 1px solid #ccc; }
    .typing-area button { margin-left: 8px; border-radius: 20px; }
    #chatWindow { overflow-y: auto; max-height: 500px; scrollbar-width: thin; scrollbar-color: #ccc transparent; }
    #chatWindow::-webkit-scrollbar { width: 4px; }
    #chatWindow::-webkit-scrollbar-track { background: transparent; }
    #chatWindow::-webkit-scrollbar-thumb { background-color: #ccc; border-radius: 10px; }
    #chatWindow::-webkit-scrollbar-button { display: none; }
    
    .wave {
      display: inline-flex;
      gap: 4px;
    }
    .wave .dot {
      display: inline-block;
      width: 3px;
      height: 3px;
      border-radius: 50%;
      background: #333;
      animation: wave 1.3s linear infinite;
    }
    .wave .dot:nth-child(2) {
      animation-delay: -1.1s;
    }
    .wave .dot:nth-child(3) {
      animation-delay: -0.9s;
    }
    
    @keyframes wave {
      0%, 60%, 100% {
        transform: translateY(0);
      }
      30% {
        transform: translateY(-10px);
      }
    }