a {
    text-decoration: none;
    color: #6c84ae;
}
a:hover {
    color: #303f49;
}

.page {
    box-shadow: 0 3px 7px #555;
    background: #FFF;
}

.content {
    margin: 7rem 1rem;
}

.book-header {
    text-align: center;
    margin-top: 5rem;
}

ul.book-navbar {
    text-align: center;
    padding: 2px 0 2px 0;
}
ul.book-navbar li {
    display: inline;
    margin-right: 1rem;
}

.exerciseQ {
    opacity: 0.7;
    margin-bottom: 4rem;
    font-size: 90%;
}

.exercise-list a {
    margin-left: 1rem;
}

.exercise-list span {
    margin-left: 1rem;
    opacity: 0.7;
}