body{
    margin: 0;
    padding: 0;
    height: 100vh;
    width: 100%;
    justify-content: center;
    font-family: "roboto", sans-serif;
    background-color: #4a1010;
}
input{
    display: none;
}
img{
    width: 100%;
    height: 100%;
}
.book{
    margin-top: 20px;
    display: flex;
}
#cover{
    width: 50%;
    height: auto;
}
.flip-book{
    width: 50%;
    height: auto;
    position: relative;
    perspective: 1500px;;
}
.flip{
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    transform-origin: left;
    transform-style: preserve-3d;
    transform: rotateY('0deg');
    transition: .5s;
    color: #000;
}
.front{
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    background-color: #fff;
    box-sizing: border-box;
    box-shadow: inset 20px 0 50px rgba(0,0,0,0.5) 0 2px 5px rgba(0,0,0,0.5);
}
.back{
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 99;
    transform: rotateY(180deg);
    backface-visibility: hidden;
    background-color: #000;
}
.next-btn{
     position: absolute;
     bottom: 4px;
     font-size: 9pt;
     right: 13px;
     cursor: pointer;
     color: #fff;
}
.back-btn{
    position: absolute;
    bottom: 4px;
     font-size: 9pt;
     left: 13px;
    cursor: pointer;
    color: #fff;
}
#p1{
    z-index: 3;
}
#p2{
    z-index: 2;
}
#p3{
    z-index: 1;
}
#c1:checked ~ .flip-book #p1{
    transform: rotateY(-180deg);
    z-index: 1;
}
#c2:checked ~ .flip-book #p2{
    transform: rotateY(-180deg);
    z-index: 2;
}
#c3:checked ~ .flip-book #p3{
    transform: rotateY(-180deg);
    z-index: 3;
}
/* LAYOUT */
.layout{
    background-color: white;
    padding: 5px;
    border-radius: 3px;
    margin-top: 30px;
}
h3{
    color: darkred;
    font-weight: bold;
    font-family: 'arial';
}
/*PRODUK PROMO*/
@media screen and (max-width: 600px) {
    img{
        width: 100%;
    }
    .next-btn{
        position: absolute;
        bottom: 2px;
        right: 10px;
        font-size: 7pt;
        cursor: pointer;
        color: #fff;
   }
   .back-btn{
       position: absolute;
       bottom: 2px;
       left: 10px;
       font-size: 7pt;
       cursor: pointer;
       color: #fff;
   }
   /* LAYOUT */
    .layout{
        border-radius: 0px;
        height: 100vh;
    }
}