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

body {
  font-family: Arial, sans-serif;
  max-width: 900px;
  margin: 30px auto;
  padding: 0 12px;
  color: #222;
  line-height: 1.6;
  background: #f6f7fb;
}

header {
  text-align: center;
  padding: 18px 14px;
  margin-bottom: 18px;

  background: #fff;
  border: 1px solid #e6e6e6;
  border-radius: 14px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.06);
}

header h1 {
  font-size: 34px;
  margin-bottom: 6px;
  letter-spacing: 0.3px;
}

header p {
  color: #555;
  font-size: 15px;
}

/* cards das seções */
main section {
  margin: 18px 0;
  padding: 16px;

  background: #fff;
  border: 1px solid #e6e6e6;
  border-radius: 14px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.06);

  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

/* efeito ao passar o mouse */
main section:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.09);
}

h2 {
  margin-bottom: 12px;
  font-size: 20px;
}

video {
  width: 100%;
  max-width: 520px;
  display: block;
  margin: 0 auto;

  border-radius: 12px;
  border: 1px solid #e6e6e6;
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.10);
}

/* borda e cantos */
audio {
  width: 100%;
  border-radius: 12px;
  border: 1px solid #e6e6e6;
  background: #fff;
  padding: 6px;
}

@media (max-width: 480px) {
  body {
    margin: 16px auto;
    padding: 0 10px;
  }

  header h1 {
    font-size: 26px;
  }

  h2 {
    font-size: 18px;
  }

  main section {
    padding: 14px;
  }
}