.cases-container {
  width: 1000px;
  background-color: #fff;
  padding: 15px 100px;
  margin: auto;
  margin-bottom: 10px;
  box-shadow: 0px 0px 5px rgba(0, 0, 0, .3);
  display: flex;
  flex-wrap: wrap;

}

.cases-box {
  position: relative;
  width: 480px;
  height: 270px;
  margin: 10px;
  overflow: hidden;
  transition: all .3s;
  cursor: pointer;
  display: block;
  box-shadow: 0px 0px 5px rgba(0, 0, 0, .3);
}

.cases-box img {
  position: absolute;
}

.mask {
  position: absolute;
  width: 100%;
  height: 100%;
  background-color: rgba(27, 31, 37, 0.8);
  margin-top: 210px;
  transition: all .3s;
  cursor: pointer;
  display: flex;
}

.mask-fl {
  width: 80px;
  height: 100%;
  background-color: rgb(27, 31, 37);
}

.mask-img {
  display: block;
  width: 40px;
  height: 40px;
  padding: 0 10px;
  opacity: 1;
  transition: all .3s;
  margin: 10px 0 0 10px;
}

.mask-fl-title {
  display: block;
  color: #fff;
  font-size: 22px;
  writing-mode: vertical-rl;
  margin-left: 25px;
  margin-top: 70px;
  letter-spacing: 15px;
  opacity: 0;
  transition: all .3s;
}

.mask-fr {
  width: 400px;
  height: 100%;
}

.mask-fr-title {
  margin-top: 17px;
  text-align: center;
  font-size: 20px;
  color: #fff;
  letter-spacing: 2px;
  transition: all .3s;
}

.mask-fr-text {
  padding: 0 30px;
  margin-top: 20px;
  color: #fff;
  line-height: 25px;
  opacity: 0;
  transition: all .3s;
}


/* 遮罩动 */
.cases-box:hover {
  transform: scale(1.05);
  box-shadow: 0px 0px 10px rgba(0, 0, 5, .8);
}

.cases-box:hover .mask {
  cursor: pointer;
  margin-top: 0px;
  transition: all .3s;
  background-color: rgba(0, 82, 217, .5);
}

/* 左边动 */
.cases-box:hover .mask-img {
  opacity: 0;
  transition: all .3s;
}

.cases-box:hover .mask-fl-title {
  opacity: 1;
  transition: all .3s;
}

/* 右边动 */
.cases-box:hover .mask-fr-title {
  margin-top: 55px;
  transition: all .3s;
}

.cases-box:hover .mask-fr-text {
  opacity: 1;
  transition: all .9s;
}