* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }

  body {
    font-family: 'Montserrat', sans-serif;
    /* defer background to global stylesheet; keep layout spacing */
    background: transparent;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    min-height: 100vh;
    padding-top: 80px; /* espaço para o header fixo */
  }

  /* Header estilo site com fundo escuro e texto branco */
  header {
    position: fixed;
    top: 0;
    width: 100%;
    height: 60px;
    background-color: #333; /* fundo cinza escuro */
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    z-index: 999;
    color: #fff; /* cor do texto do header */
  }

  /* Links do menu com ícones, com cor branca */
  header a {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: #fff; /* cor do texto dos links */
    margin: 0 20px;
    font-weight: 600;
    font-size: 15px;
    padding: 8px 12px;
    border-radius: 4px;
    transition: background-color 0.2s;
  }

  /* garantir que ao selecionar/visitar o link ele mantenha a cor e sem sublinhado */
  header a:focus,
  header a:active,
  header a:visited {
    color: #fff;
    text-decoration: none;
  }

  /* Ícones ao lado do texto */
  header a i {
    margin-right: 8px;
  }

  /* Efeito hover nos links do header */
  header a:hover {
    background-color: #555; /* tom mais claro no hover */
  }

  /* Link ativo do header (página corrente) */
  header a.active{color:#ff4d4d !important;font-weight:700}

  /* Logo estilizado: use <img> inside .logo for better control */
  .logo {
    width: 500px;
    margin: 0 auto 20px;
    text-align: center;
    display: block;
  }
  .logo img{
    max-width: 500px;
    width: 100%;
    height: auto;
    display: block;
    margin: 0 auto;
  }

  /* Prevent the logo from overflowing small screens */
  @media (max-width: 520px) {
    .logo { width: 90%; }
    .logo img { max-width: 100%; }
  }

  /* Texto de instrução */
  p.instruction {
    font-size: 18px;
    color: #333;
    margin-bottom: 20px;
    text-align: center;
  }

  /* Container do login */
  .login-box {
    background-color: #fff;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 8px 20px rgba(0,0,0,0.1);
    max-width: 380px;
    width: 100%;
  }

  /* Cabeçalho do formulário */
  .login-box h1 {
    text-align: center;
    margin-bottom: 25px;
    font-size: 28px;
    color: #222;
  }

  /* Formulário */
  form {
    display: flex;
    flex-direction: column;
  }

  input[type="text"],
  input[type="password"] {
    padding: 14px 16px;
    margin-bottom: 15px;
    border: 1px solid #ccc;
    border-radius: 10px;
    font-size: 14px;
    transition: border-color 0.3s;
  }

  input[type="text"]:focus,
  input[type="password"]:focus {
    outline: none;
    border-color: #007bff;
  }

  /* Botão de login */
  .btn-login {
    background: linear-gradient(135deg, #667eea, #764ba2);
    border: none;
    padding: 14px;
    border-radius: 10px;
    color: #fff;
    font-size: 16px;
    cursor: pointer;
    margin-top: 10px;
    transition: background 0.3s, box-shadow 0.3s;
  }

  .btn-login:hover {
    background: linear-gradient(135deg, #764ba2, #667eea);
    box-shadow: 0 4px 15px rgba(118, 75, 162, 0.3);
  }

  /* Mensagens de erro/informação */
  .alert-message {
    margin-top: 15px;
    padding: 14px;
    border-radius: 10px;
    font-weight: 600;
    font-size: 14px;
    text-align: center;
  }

  .alert-message.error {
    background-color: #c0392b;
    color: #fff;
  }

  .alert-message.info {
    background-color: #2980b9;
    color: #fff;
  }

  .alert-message.warning {
    background-color: #f39c12;
    color: #fff;
  }

  /* Rodapé */
  footer {
    margin-top: 40px;
    text-align: center;
    font-size: 14px;
    color: #777;
  }

  footer b {
    cursor: pointer;
    color: #3498db;
  }

  /* Responsividade */
  @media(max-width: 400px){
    .login-box {
      padding: 30px 20px;
    }
  }