img {
  width: 100%;
  height: 200px;
}

section {
  display: flex;
  justify-content: center;
  align-items: center;
}
.box {
  position: relative;
  width: 100%;
  height: 30%;
  display: flex;
  justify-content: center;
  align-items: center;
}

.box-content {
  width: 100%;
  height: 30%;
  position: absolute;
  color: white;
  font-weight: bold;
  background-color: rgba(0, 0, 0, 0.315);
  object-fit: cover;
  opacity: 0;
  text-align: center;
}

.box-content:hover {
  opacity: 1;
}

ul {
  list-style-type: none;
  display: flex;
  flex-flow: row wrap;
  align-items: center;
}