* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    height: 100%;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: sans-serif;
    overflow: hidden;
    background-color: black;
}

.content {
    background-color: #EDE1C0;
    width: calc(120vh);
    height: 100vh;
    padding: 50px;
    display: flex;
    align-items: center;
    flex-direction: column;
    justify-content: center;
}

.book {
    width: calc(65vh);
    position: relative;
    transition: transform 0.5s;
}

.paper {
    height: 100%;
    width: 100%;
    position: absolute;
    top: 0;
    left: 0;
    perspective: 1500px;
}

.front {
    backface-visibility: hidden;
}

.front, 
.back {
    position: absolute;
    width: 101%;
    height: 100%;
    top: 0;
    left: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    transform-origin: left;
    transition: transform 1s;
}

.front {
    z-index: 1;
}

.back {
    z-index: 0;
}

.back canvas,
.back-content {
    transform: rotateY(180deg);
}

.flipped .front,
.flipped .back {
    transform: rotateY(-180deg);
}

canvas {
    width: 100%;
    height: 100%;
}

.canvas {
    width: 50%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: white;
    transform-origin: left;
    transition: transform 0.1s;
}