*{
    margin: 6px;
    padding: 6px;
    box-sizing: border-box;
    font-family: sans-serif;
}
#contenedor{
    width: 90%;
    margin: 25px auto;
    padding: 10px;
}
#cabecera{
    border: 2px solid blue; 
    
}
#titulo{
    padding: 10px;
    text-align: center;
}
h1{
    color: red;
}
#menu{
    border: 3px solid rebeccapurple;
    box-sizing: content-box;
    width: 60%;
    list-style-type: none;
}
#contenido{
    border: 2px solid blue;
}
h2{
    color: red;
}
#contenido{
    text-align: center;
}
.nav{
    display: inline block;
    font-size: 50px;
    transition: 0.5 ease;
}
#nav:hover{
    transform: rotate(360deg);
}
.contenedor ol li img{
      display: flex;
      flex-direction: row;
      justify-content: space-between;
      width: 300px;
      height: 150px;
}
.curso{
  display: flex;
  align-items: center;
  justify-content: space-between;
  background-color: whitesmoke;
  border-left: 4px solid green;
  margin-bottom: 15px;
  padding: 15px 20px;
  border-radius: 6px;
  transition: transform 1s ease, box-shadow 1s ease;
}
.curso:hover {
  box-shadow: 0 2px 6px green;
}
.curso img {
  width: 60px;
  height: auto;
}

.curso h2 {
  margin: 0;
  font-size: 18px;
  color: black;
}

.curso p {
  margin: 4px 0 0;
  color: black;
  font-size: 14px;
}
nav {
  background-color:black;
  color:white;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 55px;
  text-align: center;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
}

nav ul li {
  margin: 0 25px;
}

nav ul li a {
  color: white;
  text-decoration: none;
  font-weight: bold;
  font-size: 16px;
  padding: 10px;
  border-radius: 4px;
  transition-duration: 10seg;
}