details:open {
  border: 2px solid #a5c2a3;
  padding: 10px;
  border-radius: 6px;
}

details > summary {
  color: black;
  font-weight: bold;
}

.mylist1 ul {
  list-style-type: square;
}

.mylist2 ul {
  list-style-type: disc;
  color: darkblue;
}

.mylist3 ul {
  list-style-type: circle;
  color:black;
}

.lesson {
  border: 2px solid #ffa62b;
  padding: 10px;
  border-radius: 6px;
  margin: 1em 0;
}

.notabene {
  background-color: #cbe3f8;
  padding: 10px;
  border-radius: 6px;
  margin: 1em 0;
}

.notabene::before {
  content: "Nota bene :";
  display: block;
  font-weight: bold;
  margin-bottom: 0.5em;
}