/* 3D Book Viewer Styles */
:root {
    --book-width: 350px;
    --book-height: 500px;
    --book-primary: #0A3D62;
    --book-accent: #FF8C00;
    --book-glow: rgba(255, 140, 0, 0.4);
    --page-bg: #fff;
}

.book-section {
    perspective: 2000px;
    padding: 100px 0;
    background: radial-gradient(circle at center, #1e375a 0%, #0a192f 100%);
    overflow: visible;
}

.book-container {
    position: relative;
    width: var(--book-width);
    height: var(--book-height);
    margin: 0 auto;
    transform-style: preserve-3d;
    transition: transform 1.5s cubic-bezier(0.19, 1, 0.22, 1);
    cursor: pointer;
}

/* Power of Book - Glow Effect */
.book-container::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 120%;
    height: 120%;
    transform: translate(-50%, -50%);
    background: radial-gradient(circle, var(--book-glow) 0%, transparent 70%);
    opacity: 0;
    transition: opacity 1s ease;
    z-index: -1;
}

.book-container.opened::before {
    opacity: 1;
    animation: pulseGlow 3s infinite alternate;
}

@keyframes pulseGlow {
    from { transform: translate(-50%, -50%) scale(1); opacity: 0.4; }
    to { transform: translate(-50%, -50%) scale(1.2); opacity: 0.8; }
}

.book {
    position: relative;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    transition: transform 1s ease;
}

/* Book State: Closed (angled) */
.book-container:not(.opened) {
    transform: rotateY(-30deg) rotateX(10deg);
}

.book-container.opened {
    transform: rotateY(0deg) rotateX(0deg) scale(1.1);
}

.book-page {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--page-bg);
    transform-origin: left;
    transform-style: preserve-3d;
    transition: transform 0.8s cubic-bezier(0.645, 0.045, 0.355, 1);
    box-shadow: inset 3px 0 10px rgba(0,0,0,0.1);
    border-radius: 0 5px 5px 0;
}

.page-front, .page-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    flex-direction: column;
    padding: 30px;
    overflow: hidden;
}

.page-back {
    transform: rotateY(180deg);
    background: #f9f9f9;
}

/* Cover Styling */
.book-page.cover {
    background: var(--book-primary);
    color: white;
    z-index: 10;
}

.cover-content {
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    border: 10px solid rgba(255,255,255,0.1);
}

.cover-logo {
    width: 80px;
    margin-bottom: 20px;
}

.cover-title {
    font-size: 2.2rem;
    font-weight: 800;
    margin-bottom: 5px;
    color: var(--book-accent);
}

.cover-subtitle {
    font-size: 1.1rem;
    opacity: 0.8;
}

/* Inside Page Content */
.page-header {
    border-bottom: 2px solid var(--book-accent);
    padding-bottom: 10px;
    margin-bottom: 20px;
}

.page-body {
    font-size: 0.95rem;
    line-height: 1.6;
    color: #333;
}

/* Flipping Logic */
.book-page.flipped {
    transform: rotateY(-180deg);
}

/* Responsive adjustments */
@media (max-width: 768px) {
    :root {
        --book-width: 300px;
        --book-height: 420px;
    }
}