@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: none; opacity: .5; transition: opacity 2s; }
.season-box:hover {opacity:1.0;}

.winter {background: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")}