@charset "UTF-8";
/* CSS Document */

.box {width: 680px;
      margin: 40px auto;
      display: flex;
      flex-wrap: wrap;}

.winter {background-image: url("images/winter.jpg");}
.spring {background-image: url("images/spring.jpg");}
.summer {background-image: url("images/summer.jpg");}
.fall {background-image: url("images/fall.jpg");}

.season-box {
              width: 330px;
              height: 214px;
              border-radius: 5px;
              display: block;
              margin: 5px;
              background-size: 100%;
              background-repeat: no-repeat;
              opacity: .5;
              transition: opacity 2s;
              }

.season-box:hover {opacity: 1.0;}