html{
    background-color: #292b2c;
}
h1{
    text-align: center;
}
th{
    margin-left: 50px;
}
section{
    display: flex;
    width:50%;
    height: 50%;
}
section h2{
    position: relative;
    /*top:100px;*/
}
.close{
    position: absolute;
    left: 10px;
    font-size: 4em;
}
.inside-info{
    display: flex;
    flex-direction: column;
}
#book-info{
    float: left;
    background-color: inherit;
}
.img-responsive{
    width: 50%;
    height: 50%;
}
.grade-up{
    display: inline-block;
}
.rating-btns{
    font-size: 4em;
}
.popup button{
    position: relative;
    left:150px;
} 
.popup{
    display: inline;
    position: absolute;
    top:90px;
    font-size: 3.2em;
    left: 200px;
    background-color: blue;
    /*width: 500px;
    height: 350px;*/
}
.undisplayed{
    display: none;
}
form div{
    display: inline;
}