/* 3D Book Flip Physics System */
.book-container {
    perspective: 1800px;
}
.book {
    position: relative;
    width: 320px;
    height: 420px;
    transition: transform 0.8s cubic-bezier(0.2, 0.8, 0.2, 1);
    transform-style: preserve-3d;
}
@media (min-width: 768px) {
    .book {
        width: 420px;
        height: 520px;
    }
}
.page {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    transform-origin: left center;
    transform-style: preserve-3d;
    transition: transform 0.8s cubic-bezier(0.4, 0, 0.2, 1), z-index 0.8s;
    backface-visibility: hidden;
}
.page-face {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: 4px 16px 16px 4px;
    box-shadow: inset -5px 0 25px rgba(0, 0, 0, 0.08), 8px 8px 30px rgba(0, 0, 0, 0.15);
    overflow: hidden;
}
.page-front {
    z-index: 2;
}
.page-back {
    transform: rotateY(180deg);
    z-index: 1;
    border-radius: 16px 4px 4px 16px;
    box-shadow: inset 5px 0 25px rgba(0, 0, 0, 0.08), -8px 8px 30px rgba(0, 0, 0, 0.15);
}
.page.flipped {
    transform: rotateY(-180deg);
}

.slider-handle::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 2px;
    height: 32px;
    background: #6366F1;
    border-radius: 1px;
}

.glass-panel {
    background: rgba(34, 45, 78, 0.65);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
}

::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: #F8FAFC;
}
::-webkit-scrollbar-thumb {
    background: #CBD5E1;
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: #4F46E5;
}