html body #books {
    padding-top: 50px !important;
}

#books ul {
    margin: 0;
    padding: 0;
    list-style: none;
}

#books a {
    color: #2c3e50;
    text-decoration: none;
}

#books .btn {
    display: flex;
    text-transform: uppercase;
    border: 2px solid #2c3e50;
    /*margin-top: 100px;*/
    font-size: 16px;
    font-weight: 700;
    padding: 0.1em 0.4em;
    text-align: center;
    -webkit-transition: color 0.3s, border-color 0.3s;
    -moz-transition: color 0.3s, border-color 0.3s;
    transition: color 0.3s, border-color 0.3s;
    color: #2c3e50;
    white-space: normal;
    max-width: 95%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    position: absolute;
    margin: 0;
    justify-content: center;
    align-items: center;
}

    #books .btn:hover {
        border-color: #321e5b;
        color: #321e5b;
    }

#books img {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    cursor: default;
    width: inherit;
    height: inherit;
}

#books li .btn {
    background: none;
    height: auto;
    min-height: 1px;
}

/* basic grid, only for this demo */
.align {
    clear: both;
    margin: 90px auto 20px;
    width: 100%;
    text-align: center;
}

    .align > li {
        width: 300px;
        min-height: 300px;
        display: inline-block;
        margin: 30px 20px 30px 30px;
        padding: 0;
        vertical-align: top;
    }

/* ///////////////////////////////////////////////////

HARDCOVER
Table of Contents

1. container
2. background & color
3. opening cover, back cover and pagees
4. position, transform y transition
5. events
6. Bonus
	- Cover design
	- Ribbon
	- Figcaption
7. mini-reset

/////////////////////////////////////////////////////*/

/*
	1. container
*/

.book {
    position: relative;
    width: 220px;
    height: 312px;
    -webkit-perspective: 1000px;
    -moz-perspective: 1000px;
    perspective: 1000px;
    -webkit-transform-style: preserve-3d;
    -moz-transform-style: preserve-3d;
    transform-style: preserve-3d;
}

/*
	2. background & color
*/

/* HARDCOVER FRONT */
.hardcover_front li:first-child {
    background-color: #eee;
    -webkit-backface-visibility: hidden;
    -moz-backface-visibility: hidden;
    backface-visibility: hidden;
}

/* reverse */
.hardcover_front li:last-child {
    background: #fffbec;
}

/* HARDCOVER BACK */
.hardcover_back li:first-child {
    background: #fffbec;
}

/* reverse */
.hardcover_back li:last-child {
    background: #fffbec;
}

.book_spine li:first-child {
    background: #eee;
}

.book_spine li:last-child {
    background: #333;
}

    /* thickness of cover */

    .hardcover_front li:first-child:after,
    .hardcover_front li:first-child:before,
    .hardcover_front li:last-child:after,
    .hardcover_front li:last-child:before,
    .hardcover_back li:first-child:after,
    .hardcover_back li:first-child:before,
    .hardcover_back li:last-child:after,
    .hardcover_back li:last-child:before,
    .book_spine li:first-child:after,
    .book_spine li:first-child:before,
    .book_spine li:last-child:after,
    .book_spine li:last-child:before {
        background: #999;
    }

/* pagee */

.pagee > li {
    background: -webkit-linear-gradient(left, #e1ddd8 0%, #fffbf6 100%);
    background: -moz-linear-gradient(left, #e1ddd8 0%, #fffbf6 100%);
    background: -ms-linear-gradient(left, #e1ddd8 0%, #fffbf6 100%);
    background: linear-gradient(left, #e1ddd8 0%, #fffbf6 100%);
    box-shadow: inset 0px -1px 2px rgba(50, 50, 50, 0.1), inset -1px 0px 1px rgba(150, 150, 150, 0.2);
    border-radius: 0px 5px 5px 0px;
}

/*
	3. opening cover, back cover and pagees
*/

.hardcover_front {
    -webkit-transform: rotateY(-34deg) translateZ(8px);
    -moz-transform: rotateY(-34deg) translateZ(8px);
    transform: rotateY(-34deg) translateZ(8px);
    z-index: 100;
}

.hardcover_back {
    -webkit-transform: rotateY(-15deg) translateZ(-8px);
    -moz-transform: rotateY(-15deg) translateZ(-8px);
    transform: rotateY(-15deg) translateZ(-8px);
}

.pagee li:nth-child(1) {
    -webkit-transform: rotateY(-28deg);
    -moz-transform: rotateY(-28deg);
    transform: rotateY(-28deg);
}

.pagee li:nth-child(2) {
    -webkit-transform: rotateY(-30deg);
    -moz-transform: rotateY(-30deg);
    transform: rotateY(-30deg);
}

.pagee li:nth-child(3) {
    -webkit-transform: rotateY(-32deg);
    -moz-transform: rotateY(-32deg);
    transform: rotateY(-32deg);
}

.pagee li:nth-child(4) {
    -webkit-transform: rotateY(-34deg);
    -moz-transform: rotateY(-34deg);
    transform: rotateY(-34deg);
}

.pagee li:nth-child(5) {
    -webkit-transform: rotateY(-36deg);
    -moz-transform: rotateY(-36deg);
    transform: rotateY(-36deg);
}

/*
	4. position, transform & transition
*/

.hardcover_front,
.hardcover_back,
.book_spine,
.hardcover_front li,
.hardcover_back li,
.book_spine li {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    -webkit-transform-style: preserve-3d;
    -moz-transform-style: preserve-3d;
    transform-style: preserve-3d;
}

.hardcover_front,
.hardcover_back {
    -webkit-transform-origin: 0% 100%;
    -moz-transform-origin: 0% 100%;
    transform-origin: 0% 100%;
}

.hardcover_front {
    -webkit-transition: all 0.8s ease, z-index 0.6s;
    -moz-transition: all 0.8s ease, z-index 0.6s;
    transition: all 0.8s ease, z-index 0.6s;
}

    /* HARDCOVER front */
    .hardcover_front li:first-child {
        cursor: default;
        -webkit-user-select: none;
        -moz-user-select: none;
        user-select: none;
        -webkit-transform: translateZ(2px);
        -moz-transform: translateZ(2px);
        transform: translateZ(2px);
    }

    .hardcover_front li:last-child {
        -webkit-transform: rotateY(180deg) translateZ(2px);
        -moz-transform: rotateY(180deg) translateZ(2px);
        transform: rotateY(180deg) translateZ(2px);
    }

/* HARDCOVER back */
.hardcover_back li:first-child {
    -webkit-transform: translateZ(2px);
    -moz-transform: translateZ(2px);
    transform: translateZ(2px);
}

.hardcover_back li:last-child {
    -webkit-transform: translateZ(-2px);
    -moz-transform: translateZ(-2px);
    transform: translateZ(-2px);
}

    /* thickness of cover */
    .hardcover_front li:first-child:after,
    .hardcover_front li:first-child:before,
    .hardcover_front li:last-child:after,
    .hardcover_front li:last-child:before,
    .hardcover_back li:first-child:after,
    .hardcover_back li:first-child:before,
    .hardcover_back li:last-child:after,
    .hardcover_back li:last-child:before,
    .book_spine li:first-child:after,
    .book_spine li:first-child:before,
    .book_spine li:last-child:after,
    .book_spine li:last-child:before {
        position: absolute;
        top: 0;
        left: 0;
        content: '';
    }

/* HARDCOVER front */
.hardcover_front li:first-child:after,
.hardcover_front li:first-child:before {
    width: 4px;
    height: 100%;
}

.hardcover_front li:first-child:after {
    -webkit-transform: rotateY(90deg) translateZ(-2px) translateX(2px);
    -moz-transform: rotateY(90deg) translateZ(-2px) translateX(2px);
    transform: rotateY(90deg) translateZ(-2px) translateX(2px);
}

.hardcover_front li:first-child:before {
    -webkit-transform: rotateY(90deg) translateZ(158px) translateX(2px);
    -moz-transform: rotateY(90deg) translateZ(158px) translateX(2px);
    transform: rotateY(90deg) translateZ(158px) translateX(2px);
}

.hardcover_front li:last-child:after,
.hardcover_front li:last-child:before {
    width: 4px;
    height: 160px;
}

.hardcover_front li:last-child:after {
    -webkit-transform: rotateX(90deg) rotateZ(90deg) translateZ(80px) translateX(-2px) translateY(-78px);
    -moz-transform: rotateX(90deg) rotateZ(90deg) translateZ(80px) translateX(-2px) translateY(-78px);
    transform: rotateX(90deg) rotateZ(90deg) translateZ(80px) translateX(-2px) translateY(-78px);
}

.hardcover_front li:last-child:before {
    box-shadow: 0px 0px 30px 5px #333;
    -webkit-transform: rotateX(90deg) rotateZ(90deg) translateZ(-230px) translateX(-2px) translateY(-78px);
    -moz-transform: rotateX(90deg) rotateZ(90deg) translateZ(-230px) translateX(-2px) translateY(-78px);
    transform: rotateX(90deg) rotateZ(90deg) translateZ(-230px) translateX(-2px) translateY(-78px);
}

/* thickness of cover */

.hardcover_back li:first-child:after,
.hardcover_back li:first-child:before {
    width: 4px;
    height: 100%;
}

.hardcover_back li:first-child:after {
    -webkit-transform: rotateY(90deg) translateZ(-2px) translateX(2px);
    -moz-transform: rotateY(90deg) translateZ(-2px) translateX(2px);
    transform: rotateY(90deg) translateZ(-2px) translateX(2px);
}

.hardcover_back li:first-child:before {
    -webkit-transform: rotateY(90deg) translateZ(158px) translateX(2px);
    -moz-transform: rotateY(90deg) translateZ(158px) translateX(2px);
    transform: rotateY(90deg) translateZ(158px) translateX(2px);
}

.hardcover_back li:last-child:after,
.hardcover_back li:last-child:before {
    width: 4px;
    height: 160px;
}

.hardcover_back li:last-child:after {
    -webkit-transform: rotateX(90deg) rotateZ(90deg) translateZ(80px) translateX(2px) translateY(-78px);
    -moz-transform: rotateX(90deg) rotateZ(90deg) translateZ(80px) translateX(2px) translateY(-78px);
    transform: rotateX(90deg) rotateZ(90deg) translateZ(80px) translateX(2px) translateY(-78px);
}

.hardcover_back li:last-child:before {
    box-shadow: 10px -1px 80px 20px #666;
    -webkit-transform: rotateX(90deg) rotateZ(90deg) translateZ(-230px) translateX(2px) translateY(-78px);
    -moz-transform: rotateX(90deg) rotateZ(90deg) translateZ(-230px) translateX(2px) translateY(-78px);
    transform: rotateX(90deg) rotateZ(90deg) translateZ(-230px) translateX(2px) translateY(-78px);
}

/* BOOK SPINE */
.book_spine {
    -webkit-transform: rotateY(60deg) translateX(-5px) translateZ(-12px);
    -moz-transform: rotateY(60deg) translateX(-5px) translateZ(-12px);
    transform: rotateY(60deg) translateX(-5px) translateZ(-12px);
    width: 16px;
    z-index: 0;
}

    .book_spine li:first-child {
        -webkit-transform: translateZ(2px);
        -moz-transform: translateZ(2px);
        transform: translateZ(2px);
    }

    .book_spine li:last-child {
        -webkit-transform: translateZ(-2px);
        -moz-transform: translateZ(-2px);
        transform: translateZ(-2px);
    }

    /* thickness of book spine */
    .book_spine li:first-child:after,
    .book_spine li:first-child:before {
        width: 4px;
        height: 100%;
    }

    .book_spine li:first-child:after {
        -webkit-transform: rotateY(90deg) translateZ(-2px) translateX(2px);
        -moz-transform: rotateY(90deg) translateZ(-2px) translateX(2px);
        transform: rotateY(90deg) translateZ(-2px) translateX(2px);
    }

    .book_spine li:first-child:before {
        -webkit-transform: rotateY(-90deg) translateZ(-12px);
        -moz-transform: rotateY(-90deg) translateZ(-12px);
        transform: rotateY(-90deg) translateZ(-12px);
    }

    .book_spine li:last-child:after,
    .book_spine li:last-child:before {
        width: 4px;
        height: 16px;
    }

    .book_spine li:last-child:after {
        -webkit-transform: rotateX(90deg) rotateZ(90deg) translateZ(8px) translateX(2px) translateY(-6px);
        -moz-transform: rotateX(90deg) rotateZ(90deg) translateZ(8px) translateX(2px) translateY(-6px);
        transform: rotateX(90deg) rotateZ(90deg) translateZ(8px) translateX(2px) translateY(-6px);
    }

    .book_spine li:last-child:before {
        box-shadow: 5px -1px 100px 40px rgba(0, 0, 0, 0.2);
        -webkit-transform: rotateX(90deg) rotateZ(90deg) translateZ(-300px) translateX(2px) translateY(-6px);
        -moz-transform: rotateX(90deg) rotateZ(90deg) translateZ(-300px) translateX(2px) translateY(-6px);
        transform: rotateX(90deg) rotateZ(90deg) translateZ(-300px) translateX(2px) translateY(-6px);
    }

.pagee,
.pagee > li {
    position: absolute;
    top: 0;
    left: 0;
    -webkit-transform-style: preserve-3d;
    -moz-transform-style: preserve-3d;
    transform-style: preserve-3d;
}

.pagee {
    width: 100%;
    height: 98%;
    top: 1%;
    left: 3%;
    z-index: 10;
}

    .pagee > li {
        width: 100%;
        height: 100%;
        -webkit-transform-origin: left center;
        -moz-transform-origin: left center;
        transform-origin: left center;
        -webkit-transition-property: transform;
        -moz-transition-property: transform;
        transition-property: transform;
        -webkit-transition-timing-function: ease;
        -moz-transition-timing-function: ease;
        transition-timing-function: ease;
    }

        .pagee > li:nth-child(1) {
            -webkit-transition-duration: 0.6s;
            -moz-transition-duration: 0.6s;
            transition-duration: 0.6s;
        }

        .pagee > li:nth-child(2) {
            -webkit-transition-duration: 0.6s;
            -moz-transition-duration: 0.6s;
            transition-duration: 0.6s;
        }

        .pagee > li:nth-child(3) {
            -webkit-transition-duration: 0.4s;
            -moz-transition-duration: 0.4s;
            transition-duration: 0.4s;
        }

        .pagee > li:nth-child(4) {
            -webkit-transition-duration: 0.5s;
            -moz-transition-duration: 0.5s;
            transition-duration: 0.5s;
        }

        .pagee > li:nth-child(5) {
            -webkit-transition-duration: 0.6s;
            -moz-transition-duration: 0.6s;
            transition-duration: 0.6s;
        }

/*
	5. events
*/
.book:hover > .hardcover_front,
.book.open > .hardcover_front {
    -webkit-transform: rotateY(-145deg) translateZ(0);
    -moz-transform: rotateY(-145deg) translateZ(0);
    transform: rotateY(-145deg) translateZ(0);
    z-index: 0;
}

.book:hover > .pagee li:nth-child(1),
.book.open > .pagee li:nth-child(1) {
    -webkit-transform: rotateY(-30deg);
    -moz-transform: rotateY(-30deg);
    transform: rotateY(-30deg);
    -webkit-transition-duration: 1.5s;
    -moz-transition-duration: 1.5s;
    transition-duration: 1.5s;
}

.book:hover > .pagee li:nth-child(2),
.book.open > .pagee li:nth-child(2) {
    -webkit-transform: rotateY(-35deg);
    -moz-transform: rotateY(-35deg);
    transform: rotateY(-35deg);
    -webkit-transition-duration: 1.8s;
    -moz-transition-duration: 1.8s;
    transition-duration: 1.8s;
}

.book:hover > .pagee li:nth-child(3),
.book.open > .pagee li:nth-child(3) {
    -webkit-transform: rotateY(-118deg);
    -moz-transform: rotateY(-118deg);
    transform: rotateY(-118deg);
    -webkit-transition-duration: 1.6s;
    -moz-transition-duration: 1.6s;
    transition-duration: 1.6s;
}

.book:hover > .pagee li:nth-child(4),
.book.open > .pagee li:nth-child(4) {
    -webkit-transform: rotateY(-130deg);
    -moz-transform: rotateY(-130deg);
    transform: rotateY(-130deg);
    -webkit-transition-duration: 1.4s;
    -moz-transition-duration: 1.4s;
    transition-duration: 1.4s;
}

.book:hover > .pagee li:nth-child(5),
.book.open > .pagee li:nth-child(5) {
    -webkit-transform: rotateY(-140deg);
    -moz-transform: rotateY(-140deg);
    transform: rotateY(-140deg);
    -webkit-transition-duration: 1.2s;
    -moz-transition-duration: 1.2s;
    transition-duration: 1.2s;
}

/*
	6. Bonus
*/

/* cover CSS */

.coverDesign {
    position: absolute;
    top: 0;
    left: 0;
    bottom: 0;
    right: 0;
    overflow: hidden;
    z-index: 1;
    -webkit-backface-visibility: hidden;
    -moz-backface-visibility: hidden;
    backface-visibility: hidden;
}

    .coverDesign::after {
        background-image: -webkit-linear-gradient( -135deg, rgba(255, 255, 255, 0.45) 0%, transparent 100%);
        background-image: -moz-linear-gradient( -135deg, rgba(255, 255, 255, 0.45) 0%, transparent 100%);
        background-image: linear-gradient( -135deg, rgba(255, 255, 255, 0.45) 0%, transparent 100%);
        position: absolute;
        top: 0;
        left: 0;
        bottom: 0;
        right: 0;
    }

    .coverDesign h1 {
        color: #fff;
        font-size: 2.2em;
        letter-spacing: 0.05em;
        text-align: center;
        margin: 54% 0 0 0;
        text-shadow: -1px -1px 0 rgba(0,0,0,0.1);
    }

    .coverDesign p {
        color: #f8f8f8;
        font-size: 1em;
        text-align: center;
        text-shadow: -1px -1px 0 rgba(0,0,0,0.1);
    }

.yellow {
    background-color: #f1c40f;
    background-image: -webkit-linear-gradient(top, #f1c40f 58%, #e7ba07 0%);
    background-image: -moz-linear-gradient(top, #f1c40f 58%, #e7ba07 0%);
    background-image: linear-gradient(top, #f1c40f 58%, #e7ba07 0%);
}

.blue {
    background-color: #3498db;
    background-image: -webkit-linear-gradient(top, #3498db 58%, #2a90d4 0%);
    background-image: -moz-linear-gradient(top, #3498db 58%, #2a90d4 0%);
    background-image: linear-gradient(top, #3498db 58%, #2a90d4 0%);
}

.grey {
    background-color: #f8e9d1;
    background-image: -webkit-linear-gradient(top, #f8e9d1 58%, #e7d5b7 0%);
    background-image: -moz-linear-gradient(top, #f8e9d1 58%, #e7d5b7 0%);
    background-image: linear-gradient(top, #f8e9d1 58%, #e7d5b7 0%);
}

/* Basic ribbon */

.ribbon {
    background: #c0392b;
    color: #fff;
    display: block;
    font-size: 0.7em;
    position: absolute;
    top: 11px;
    right: 1px;
    width: 40px;
    height: 20px;
    line-height: 20px;
    letter-spacing: 0.15em;
    text-align: center;
    -webkit-transform: rotateZ(45deg) translateZ(1px);
    -moz-transform: rotateZ(45deg) translateZ(1px);
    transform: rotateZ(45deg) translateZ(1px);
    -webkit-backface-visibility: hidden;
    -moz-backface-visibility: hidden;
    backface-visibility: hidden;
    z-index: 10;
}

    .ribbon::before,
    .ribbon::after {
        position: absolute;
        top: -20px;
        width: 0;
        height: 0;
        border-bottom: 20px solid #c0392b;
        border-top: 20px solid transparent;
    }

    .ribbon::before {
        left: -20px;
        border-left: 20px solid transparent;
    }

    .ribbon::after {
        right: -20px;
        border-right: 20px solid transparent;
    }

/* figcaption */

figcaption {
    padding-left: 40px;
    text-align: left;
    position: absolute;
    top: 0%;
    left: 160px;
    width: 310px;
    -webkit-backface-visibility: hidden;
}

    figcaption h1 {
        margin: 0;
    }

    figcaption span {
        color: #321e5b;
        padding: 0.6em 0 1em 0;
        display: block;
    }

    figcaption p {
        color: #63707d;
        line-height: 1.3;
    }

.book ul.pagee li:nth-child(3):before {
    content: "TO DO";
    padding: 10px;
    border-radius: 4px;
    border: 2px solid darkred;
    color: darkred;
    font-weight: bold;
    display: inline-block;
    transform: scaleX(-1) rotate(-10deg) translate(50%, -50%);
    position: absolute;
    top: 50%;
    left: 50%;
}

.book.completed ul.pagee li:nth-child(3):before {
    content: "COMPLETED";
    border-color: darkgreen;
    color: darkgreen;
}

/* Media Queries */
@media screen and (max-width: 37.8125em) {
    .align > li {
        width: 100%;
        min-height: 440px;
        height: auto;
        padding: 0;
        margin: 0 0 30px 0;
    }

    .book {
        margin: 0 auto;
    }

    figcaption {
        text-align: center;
        width: 320px;
        top: 250px;
        padding-left: 0;
        left: -80px;
        font-size: 90%;
    }
}