.tabella {position: relative; top: 0px; left: 0px; text-align: center; line-height: 30px;}

.riga {position: relative; top: 0px; left: 0px; width: 500px; height: 40px;}

.casella_centrale {position: absolute; background: #ccc; top: 10px; left: 80px; width: 340px; height: 30px; font-weight: bold;}

.casella1 {position: absolute; background: #ddd; top: 10px; left: 10px; width: 60px; height: 30px;}
.casella2 {position: absolute; background: #DDD; top: 10px; left: 80px; width: 60px; height: 30px;}
.casella3 {position: absolute; background: #DDD; top: 10px; left: 150px; width: 60px; height: 30px;}
.casella4 {position: absolute; background: #DDD; top: 10px; left: 220px; width: 60px; height: 30px;}
.casella5 {position: absolute; background: #DDD; top: 10px; left: 290px; width: 60px; height: 30px;}
.casella6 {position: absolute; background: #DDD; top: 10px; left: 360px; width: 60px; height: 30px;}
.casella7 {position: absolute; background: #DDD; top: 10px; left: 430px; width: 60px; height: 30px;}