body,ul{
  align-items: center;
  justify-content: center;
}

body{
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  margin: 0;
}

h1{
  /* margin:auto; */
  text-align: center;
}

menu,.molecule,.documentation{
  flex:1;
}

.molecule,.documentation{
  align-items: center;
  justify-content: center;
  display: flex;
  flex-direction: column;
}

button {
  border: none;
  padding: 15px 32px;
  text-align: center;
  text-decoration: none;
  font-size: 16px;
  margin-top: 1rem;
  margin-bottom: 1rem;
  border-radius: 4px;
  background-color: #555555;
  color: white;
  transition-duration: 0.4s;
}
img {
  height: 200px;
  width: 300px;
  object-fit: contain;
}