* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #111827;
  color: #222;
}

header {
  text-align: center;
  background: #0b0f19;
  color: #f5c542;
  padding: 35px 20px;
  border-bottom: 2px solid #f5c542;
}

header h1 {
  margin: 0 0 8px;
  font-size: 38px;
}

header p {
  margin: 0;
  color: #ddd;
}

main {
  width: 90%;
  max-width: 1000px;
  margin: 30px auto;
}

.exercicio {
  background: #f8f8f8;
  margin-bottom: 28px;
  padding: 24px;
  border-radius: 8px;
}

.exercicio h2 {
  margin-top: 0;
  font-size: 20px;
  border-bottom: 1px solid #ccc;
  padding-bottom: 10px;
}

.lista-quadrada {
  list-style-type: square;
}

.lista-romana {
  list-style-type: upper-roman;
}

.lista-icone {
  list-style-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24'%3E%3Cpath fill='%23f5c542' d='M12 2l3.09 6.26L22 9.27l-5 4.87 1.18 6.88L12 17.77l-6.18 3.25L7 14.14 2 9.27l6.91-1.01z'/%3E%3C/svg%3E");
}

.lista-inside {
  list-style-position: inside;
  padding-left: 0;
}

.lista-inside li {
  border: 1px solid #bbb;
  padding: 12px;
  margin-bottom: 10px;
}

.alerta {
  border: 2px solid #b91c1c;
  border-radius: 8px;
  background: #fee2e2;
  padding: 18px;
}

.botao {
  display: inline-block;
  border: 3px dashed #b8860b;
  background: #fff8dc;
  color: #6b4f00;
  font-weight: bold;
  text-decoration: none;
  padding: 14px 20px;
}

.moldura {
  width: 350px;
  height: 160px;
  max-width: 100%;
  background: #1f2937;
  color: #f5c542;
  border-radius: 35px 5px 45px 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  border: 2px solid #f5c542;
}

.tabela-collapse {
  width: 100%;
  border-collapse: collapse;
}

.tabela-collapse th,
.tabela-collapse td {
  border: 1px solid #333;
  padding: 10px;
  text-align: left;
}

.tabela-collapse th {
  background: #1f2937;
  color: #f5c542;
}

.tabela-spacing {
  width: 100%;
  border-collapse: separate;
  border-spacing: 12px;
}

.tabela-spacing th,
.tabela-spacing td {
  border: 1px solid #333;
  padding: 10px;
  background: #fafafa;
}

.outline-basico {
  width: 320px;
  max-width: 100%;
  padding: 25px;
  background: #fff6a8;
  border: 4px solid #000;
  outline: 4px solid #f5c542;
}

.outline-offset {
  border: 4px solid #333;
  outline: 3px solid #f5c542;
  outline-offset: 10px;
  padding: 20px;
  margin: 20px 12px;
}

.cartao-sombra {
  max-width: 420px;
  padding: 25px;
  background: white;
  box-shadow: 5px 8px 18px rgba(0, 0, 0, 0.45);
}

.dicas {
  padding: 25px;
  background: #eeeeee;
  box-shadow: inset 0 0 15px rgba(0, 0, 0, 0.25);
}

.anuncio {
  display: inline-block;
  padding: 25px 35px;
  background: #171717;
  color: #f5c542;
  box-shadow: 0 0 12px 10px rgba(245, 197, 66, 0.35);
  font-weight: bold;
}

.bloco-centralizado {
  width: 65%;
  margin-left: auto;
  margin-right: auto;
  padding: 25px;
  text-align: center;
  background: #1f2937;
  color: white;
  border: 1px solid #f5c542;
}

.menu {
  background: #111827;
  padding: 10px;
}

.menu ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.menu li {
  display: inline-block;
}

.menu a {
  display: block;
  color: #f5c542;
  text-decoration: none;
  padding: 12px 18px;
}

.menu a:hover {
  background: #374151;
}

.dimensoes {
  max-width: 300px;
  min-height: 120px;
  padding: 20px;
  background: #1f2937;
  color: white;
  border: 1px solid #f5c542;
}

.passos {
  display: flex;
  gap: 12px;
}

.passos div {
  padding: 25px;
  background: #1f2937;
  color: #f5c542;
  border: 1px solid #f5c542;
  text-align: center;
  flex: 1;
}

.oculto-visibility {
  visibility: hidden;
}

.oculto-display {
  display: none;
}

.feedbacks {
  display: flex;
  gap: 20px;
}

.feedback {
  flex: 1;
  padding: 25px;
  background: #1f2937;
  color: #f5c542;
  border: 1px solid #f5c542;
  text-align: center;
  font-weight: bold;
}

.opacidade-1 {
  opacity: 1;
}

.opacidade-05 {
  opacity: 0.5;
}

.opacidade-025 {
  opacity: 0.25;
}

footer {
  text-align: center;
  padding: 25px;
  background: #0b0f19;
  color: #f5c542;
}

@media (max-width: 650px) {
  .feedbacks,
  .passos {
    flex-direction: column;
  }

  .bloco-centralizado {
    width: 100%;
  }
}