.zone { width: 960px; margin-left: auto; margin-right: auto; }

.grid-12-1, .grid-12-2, .grid-12-3, .grid-12-4, .grid-12-5,
.grid-12-6, .grid-12-7, .grid-12-8, .grid-12-9, .grid-12-10, 
.grid-12-11, .grid-12-12 { margin-left: 10px; margin-right: 10px; }

.grid-12-1 { width: 60px; }     
.grid-12-2 { width: 140px; }
.grid-12-3 { width: 220px; }
.grid-12-4 { width: 300px; }
.grid-12-5 { width: 380px; }
.grid-12-6 { width: 460px; }
.grid-12-7 { width: 540px; }
.grid-12-8 { width: 620px; }
.grid-12-9 { width: 700px; }
.grid-12-10 { width: 780px; }
.grid-12-11 { width: 860px; }
.grid-12-12 { width: 940px; }