index.css

#menu {
  display: flex;
  flex-direction: column;
  text-align: center;
  background-color: var(--secondary-bg-color);
  padding: 2rem;
  border-radius: 1rem;
  justify-content: center;
  align-items: center;
  box-shadow: var(--shadow);
}

#lab-list {
  display: grid;
  list-style-type: none;
  padding: 2rem;
  background-color: var(--tertiary-bg-color);
  border-radius: 1rem;
  margin: 0 auto;
  width: 90%;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  box-shadow: var(--shadow);
}

#lab-list li a {
  display: inline-block;
  vertical-align: top;
  padding: 1.5rem 3rem;
  border-radius: 0.5rem;
  background-color: var(--action-color);
  box-shadow: var(--shadow);
  text-decoration: none;
  color: var(--text-color);
}

#lab-list li a:hover {
  background-color: var(--action-hover-color);
}