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

body {
  font-family: Georgia, "Times New Roman", serif;
  background: #f4f4f4;
  color: #111;
  line-height: 1.6;
}

/* HEADER */
header {
  background: #ffffff;
  border-bottom: 1px solid #ccc;
  padding: 20px;
  text-align: center;
}

header h1 {
  font-size: 28px;
  margin-bottom: 5px;
}

header p {
  font-size: 14px;
  color: #555;
}

nav {
  margin-top: 10px;
}

nav a {
  color: #000;
  text-decoration: none;
  font-size: 13px;
  margin: 0 5px;
}

nav a:hover {
  text-decoration: underline;
}

/* MAIN */
main {
  max-width: 900px;
  margin: 20px auto;
  padding: 10px;
  display: flex;
  gap: 20px;
}

/* CATEGORIAS */
#categorias {
  width: 220px;
  background: #fff;
  border: 1px solid #ccc;
  padding: 15px;
}

#categorias h2 {
  font-size: 16px;
  margin-bottom: 10px;
  border-bottom: 1px solid #ccc;
}

#categorias ul {
  list-style: none;
}

#categorias li {
  margin-bottom: 8px;
}

#categorias a {
  color: #000;
  text-decoration: none;
  font-size: 14px;
}

#categorias a:hover {
  text-decoration: underline;
}

/* ARTICULOS */
#articulos {
  flex: 1;
}

.article {
  background: #ffffff;
  border: 1px solid #ccc;
  padding: 15px;
  margin-bottom: 15px;
}

.article h3 {
  font-size: 18px;
  margin-bottom: 5px;
}

.article .meta {
  font-size: 12px;
  color: #666;
  margin-bottom: 10px;
}

.article p {
  font-size: 14px;
}

/* FOOTER */
footer {
  text-align: center;
  font-size: 12px;
  color: #555;
  padding: 15px;
  border-top: 1px solid #ccc;
  background: #fff;
}

/* RESPONSIVE */
@media (max-width: 700px) {
  main {
    flex-direction: column;
  }

  #categorias {
    width: 100%;
  }
}