@charset "UTF-8";
/* CSS Document */
.box {width: 680px;margin: 40px auto; display: flex; flex-wrap: wrap;}
.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;}

.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");}