body{
	--text-color: #222;
 	--bkg-color: #fff;
	--link-color: blue;
 	background: var(--bkg-color);
 	color:  var(--text-color);
	font-family: "Open Sans", sans-serif;
}

.dark-theme{
	--bkg-color : #121212;
	--text-color : #eee;
	--link-color: #cccca0;
}

.content{
	max-width: 800px;
}

nav{
	 width: 100%;
	 display: flex;
}

p{
	max-width: 100%;
	line-height: 30px;
	text-rendering: optimizelegibility !important;
}

.centered {
	margin: 0 auto;
	width: 100%;
	max-width: fit-content;
}

li{
	line-height: calc(1ex / 0.32);
}

.navbar-links{
	display: flex;
    flex-wrap: nowrap;
    flex-direction: row;
    align-content: center;
    justify-content: space-around;
    align-items: center;
}

.navbar-links li{
	list-style: none;
}

a{
	color: var(--link-color);
}

code {
	background: var(--text-color);
    color: var(--bkg-color);
    padding: 3px 6px;
}

.navbar-links a{
	text-decoration: none;
	color: var(--text-color);
    font-weight: 700;
}

nav {
	border-bottom: 1px solid lightgrey;
}

footer{
	border-top: 1px solid lightgrey;
	display: flex;
}

.brand{
	text-decoration: none;
}

.footer-links{
	width: 100%;
}

.footer-links ul{
	display: flex;
	flex-wrap: nowrap;
    align-content: center;
    justify-content: space-around;
    list-style: none;
}

/* page for book */

.book{
	display: flex;
}

.book-flex{
	display: flex;
}

.cover-book{
	border: 1px solid black;
}

.dark-btn{
    border: 1px solid var(--text-color);
    margin: 20px 10px;
}

.btn{
	display: block;
	padding: 20px;
    text-transform: uppercase;
}

.btn-purchase{
	background-color: var(--text-color);
	color: var(--bkg-color);
}

@media only screen and (min-width: 650px){
	.book{
		padding: 50px 0px;
	}

	.navbar-links{
		    margin-left: auto;
		    width: 50%;
	}

	body{
		font-size: 1em;
	}	

	.content{
		width: 70%;
		margin: 10px auto;
	}

	.book-content {
		padding-left: 30px;
	}
}

@media only screen and (max-width:  649px){
	nav{
		align-content: stretch;
    	align-items: center;
		justify-content: space-evenly;
    }

    .footer-links{
    	flex-direction: column;
    }

    .navbar-links{
    	flex-direction: column;
    }

    .dark-btn{
    	display: none;
    }
}

@supports (font-size-adjust: 1) {
    .content {
        font-size-adjust: 0.5;
    }
}