body {
      font-family: Arial, sans-serif;
      background: #f9f9f9;
      padding: 20px;
    }
    
    .welcome {
    text-align: center;
    line-height: 10px;
    }

    .welcome h1 {
    color: red;
    }

    .welcome img {
    border-radius: 100px;
    border: 3px solid #363636;
    }

    .gifani {
    width: 50%;
    max-width: 500px;
    border-radius: 20px;
    }


    .timeline {
      position: relative;
      max-width: 900px;
      margin: 0 auto;
      padding: 40px 0;
    }

    .timeline::before {
      content: '';
      position: absolute;
      top: 0;
      left: 30px;
      width: 4px;
      height: 100%;
      background-color: #bbb;
    }

    .timeline-item {
      position: relative;
      margin-bottom: 40px;
      padding-left: 60px;
      opacity: 0;
      transform: translateY(20px);
      transition: all 0.6s ease-out;
    }

    .timeline-item.visible {
      opacity: 1;
      transform: translateY(0);
    }

    .timeline-item::before {
      content: "";
      position: absolute;
      top: 10px;
      left: 22px;
      width: 16px;
      height: 16px;
      background-color: #fff;
      border: 3px solid #555;
      border-radius: 50%;
      z-index: 1;
    }

    .timeline-content {
      padding: 15px 20px;
      border-radius: 6px;
      color: white;
      box-shadow: 0 2px 8px rgba(0,0,0,0.15);
      text-indent: 20px;
      text-align: justify;
    }

    .caotiano { background-color: #000000; }
    .precambriano { background-color: #363636; }
    .hadeano { background-color: #4F4F4F; }
    .arqueano { background-color: #800000 }
    .proterozoico { background-color: #483D8B; }
    .fanerozóico { background-color: #006400; }
    
    .mesozóico { background-color: #a86f32; }
    .cenozóico { background-color: #bc3b2a; }

    .era {
      margin-top: 10px;
      margin-left: 20px;
      padding: 10px;
      border-radius: 5px;
      font-size: 14px;
      background-color: rgba(255,255,255,0.2);
    }

    .eocaotiano { background-color: #1C1C1C; }
    .neocaotiano { background-color: #1C1C1C; }
    .paleohadeano { background-color: #696969; }
    .mesohadeano { background-color: #696969; }
    .neohadeano { background-color: #696969; }
    .eoarqueano { background-color: #8B0000; }
    .paleoarqueano { background-color: #8B0000; }
    .mesoarqueano { background-color: #8B0000; }
    .neoarqueano { background-color: #8B0000; }


    .periodo {
      margin-top: 10px;
      margin-left: 20px;
      padding: 10px;
      border-radius: 5px;
      font-size: 14px;
      background-color: rgba(255,255,255,0.2);
    }
    
    .nefeleano { background-color: #363636; }
    .erebreano { background-color: #363636; }
    .hiperitiano{ background-color: #363636; }    
    .titanomaqueano { background-color: #363636; }
    .hefesteano { background-color: #808080; }
    .jacobiano { background-color: #808080; }
    .canadiano { background-color: #808080; }
    .procrusteano { background-color: #808080; }
    .acasteano { background-color: #808080; }
    .prometeano { background-color: #808080; }
´

    .jurassico { background-color: #d79b61; }
    .triassico { background-color: #c48e52; }
    .cretaceo { background-color: #bb7d42; }


    .paleogeno { background-color: #e16b5c; }
    .neogeno { background-color: #d85a4f; }
    .quaternario { background-color: #cc4b3e; }

    .timeline-content h3 {
      margin: 0;
      font-size: 20px;
    }

    .timeline-content p {
      margin: 5px 0 0;
      font-size: 14px;
      color: #eee;
    }

    .timeline-content a {
      color: #fff;
      text-decoration: underline;
    }

    .timeline-content a:hover {
      text-decoration: none;
    }
    
    footer {
    background: ;
    color: ;
    text-align: center;
    padding: 5px;
    margin-top: 20px;
    }