/* ------------------------------
   Reset e estilo base
------------------------------ */
body {
  font-family: Arial, sans-serif;
  margin: 0;
  background: #f6f7f8;
}

main {
  padding: 20px;
  text-align: center;
}

/* ------------------------------
   Menu fixo e responsivo
------------------------------ */
nav {
  background: #2b3a55;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  padding: 10px;
}

nav a {
  color: white;
  text-decoration: none;
  margin: 5px 15px;
  padding: 8px 15px;
  border-radius: 8px;
  transition: 0.3s;
  flex: 1 1 auto;
  text-align: center;
}

nav a:hover,
nav a.active {
  background: #526D82;
}

/* ------------------------------
   PDF Viewer / Embed
------------------------------ */
.pdf-page,
#pdf-viewer {
  width: 100%;
  max-width: 900px;
  display: block;
  margin: 15px auto;
  border-radius: 10px;
  box-shadow: 0 0 8px rgba(0,0,0,0.2);
  height: auto;           /* altura automática */
  max-height: 90vh;       /* não ultrapassa a tela */
  aspect-ratio: auto;     /* mantém proporção do PDF */
}

/* ------------------------------
   Responsividade geral
------------------------------ */
@media screen and (max-width: 768px) {
  nav a {
    margin: 5px 8px;
    padding: 6px 10px;
    font-size: 14px;
  }

  main {
    padding: 15px;
  }

  .pdf-page,
  #pdf-viewer {
    max-height: 70vh;
  }
}

@media screen and (max-width: 480px) {
  nav a {
    margin: 5px 5px;
    padding: 5px 8px;
    font-size: 13px;
  }

  main h1 {
    font-size: 1.5rem;
  }

  .pdf-page,
  #pdf-viewer {
    max-height: 65vh;
  }
}