main{
  margin-top: 4.1rem;
  margin-bottom: 2rem;
}
.side-bar ul {
  width: 80vw;
  display: flex;
  align-items: center;
  justify-content: center;
  list-style-type: none;
  margin: auto;
  box-shadow: 0px 6px 5px gray;
  background: #f9f9f9;
}

.side-bar ul li a {
  text-decoration: none;
  color: black;
  padding: 15px 15px;
  transition: background-color 0.4s ease-in-out, color 0.4s ease-in-out;
}
.side-bar ul li a:hover {
  background-color: #212121;
  color: aliceblue;
}

main .first {
  width: 100%;
  margin: 10px 0px 0px 0px;
}
section h1{
  color: rgb(66, 66, 66);
  padding: 15px 20px;
  border-bottom: 1px solid gray;
  margin-bottom: 5px;
}
.box-container {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 15px;
  flex-wrap: wrap;
  width: 95vw;
  margin: auto;
  padding-top: 20px;
}

.box {
  background: #f9f9f9;
  width: 310px;
  height: 511px;
  position: relative;
  overflow: hidden;
  border-radius: 5px;
  box-shadow: 0px 0px 10px 3px rgb(199, 199, 199);
}

.box .image{
  height: 333px;
  overflow: hidden;
}
.box .image img {
  width: 100%;
  height: 333px;
  object-fit: cover;
  transition: opacity 1s ease, transform 1s ease;
}

.box img.second {
  height: 315px;
  position: absolute;
  top: 0;
  left: 0;
  opacity: 0;
}

.box .sale span {
  background-color: green;
  color: white;
  position: absolute;
  top: 20px;
  z-index: 1;
  left: 20px;
  padding: 5px;
  border-radius: 4px;
}
.box .box-end {
  width: 100%;
  padding: 0 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.box .price span {
  font-size: 16px;
}
.box .price span s {
  color: orange;
  margin-left: 25px;
}

.box .star {
  margin-top: 10px;
}
.box .star span {
  margin-right: 10px;
}
.box .star img {
  width: 14px;
}

.box .size {
  display: flex;
  margin-top: 10px;
}

.box .size span {
  display: inline-block;
  font-size: 20px;
  margin-right: 20px;
}

.box .size button {
  background-color: transparent;
  text-align: center;
  border: 1px solid rgb(175, 175, 175);
  padding: 8px 15px;
  cursor: pointer;
}

.box .btnContainer {
  width: 100%;
  display: flex;
  gap: 10px;
}
.box .image:hover img.second {
  opacity: 1;
}

.box .image:hover img.first {
  opacity: 0;
}

@media only screen and(max-width:455px) {
  .box-container {
    flex-direction: column;
  }
  .box-container .box {
    width: 400px;
  }
  .side-bar ul {
    flex-wrap: wrap;
  }
}