/* Webbook */
:root {
    --book-width: 800px;
    --book-height: 600px;
}

#webbook {
    touch-action: none;
    -webkit-transform: translate3d(0, 0, 0);
    transform: translate3d(0, 0, 0);
}

#webbook .section {
    width: 100%;
    height: 100dvh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #0c209e;
    perspective: 3000px;
}

.book {
    position: relative;
    width: var(--book-width);
    height: var(--book-height);
    transform-style: preserve-3d;
    transform: rotateX(20deg) translate3d(0, 0, 0);
    -webkit-transform: rotateX(20deg) translate3d(0, 0, 0);
    transform-origin: center center;
}

@media screen and (max-width: 900px) {
#webbook .section {
    perspective: 5000px;
}

.book {
    transform: rotateX(20deg) scale(0.8);
}
}

@media screen and (max-width: 700px) {
#webbook .section {
    perspective: 7000px;
}

.book {
    transform: rotateX(20deg) scale(0.6);
}
}

@media screen and (max-width: 500px) {
#webbook .section {
    perspective: 9000px;
}

.book {
    transform: rotateX(10deg) scale(0.4);
}
}

.leaf {
    position: absolute;
    left: calc(var(--book-width) / 2);
    width: 50%;
    height: 100%;
    transform-style: preserve-3d;
    transition: transform 2s ease-out;
    cursor: pointer;
    transform: rotateY(0deg) translateZ(0) translate3d(0, 0, 0);
    -webkit-transform: translate3d(0, 0, 0);
    transform-origin: left center;
    will-change: -webkit-transform;
}

.leaf.flipped {
    transform: rotateY(-180deg) translateZ(0) translate3d(0, 0, 0);
    -webkit-transform: translate3d(0, 0, 0) rotateY(-180deg);
    transform-origin: left center;
}

.page {
    position: absolute;
    width: 100%;
    height: 100%;
    left: 0;
    top: 0;
    font-family: 'Gothic A1', serif;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    transform: translateZ(0) translate3d(0, 0, 0);
    -webkit-transform: translateZ(0) translate3d(0, 0, 0);
    will-change: -webkit-transform;
}

.page.front {
    left: 0;
    background: linear-gradient(90deg, #555, #aaa 3%, #fff);
}

.page.back {
    left: 0;
    transform: rotateY(180deg);
    background: linear-gradient(270deg, #555, #aaa 3%, #fff);
}

.page-content {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    overflow: hidden;
    user-select: none;
    -webkit-user-select: none;
}

.page.front .page-content {
    padding: 1rem 1rem 1rem 1.75rem;
}

.page.back .page-content {
    padding: 1rem 1.75rem 1rem 1rem;
}

.page-content.image {
    justify-content: center;
    align-items: center;
}

.page.front .page-content.image {
    padding: 4rem;
}

.page.back .page-content.image {
    padding: 4rem;
}

.page-content.overflow {
    overflow-y: auto;
}

.page-content .en {
    position: relative;
    font-size: 1.25rem;
    top: 0.05rem;
}

.page-content a {
    color: blue;
    text-decoration: underline;
}

/* .page-content img {
width: 100%;
height: auto;
object-fit: contain;
max-height: 100%;
} */

.page-content h1 {
    font-weight: 400;
    font-size: 1.5rem;
    line-height: 1.4;
}

.page-content p {
    font-weight: 400;
    font-size: 1.5rem;
    line-height: 1.4;
}