.ex1 {
  display: flex;
  justify-content: center;
  margin-top: 4rem;
}
.ex1 li {
  width: 25%;
}
.ex1 img{
  display: flex;
  width: 12rem;
}
.ex1 figure{
  display: flex;
  flex-direction: column;
  align-items: center;
  gap:1.5rem;
  text-align: center;
}
.ex1 figure b{
  font-size: 1.8rem;
  font-weight: 700;
  display: block;
  color:#000;
}
.ex1 figure span{
  font-size: 1.4rem;
  font-weight: 400;
  color: #666;
  display: block;
}
.text-justify {text-align:justify}