@media screen and (max-width: 1020px){
  
  a.link {
    text-decoration: underline;
  }
  section nav ul {
    flex-direction: column;
    margin: 20px 0;
  }
  section nav ul li {
    margin: 0;
  }
  section nav ul li:nth-child(n+2) {
    margin-left: 0;
    margin-top: 30px;
  }
  section nav ul li:nth-child(-n+4)::after {
    top: initial;
    right: initial;
    bottom: -26px;
    left: 50%;
    transform: translateX(-50%) rotate(90deg);
  }
}