/* CSS Custom Properties */
:root {
    --bg-primary: #FFF8E7;
    --accent-yellow: #FFD93D;
    --accent-coral: #FF6B6B;
    --accent-teal: #4ECDC4;
    --accent-purple: #9B59B6;
    --text-dark: #2C3E50;
    --text-light: #FFFFFF;
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-primary);
}

/* Animation container */
#animation-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: 1;
}

/* Book card styling */
.book-card {
    position: absolute;
    width: 120px;
    height: 180px;
    border-radius: 4px;
    overflow: hidden;
    box-shadow:
        4px 4px 15px rgba(0, 0, 0, 0.35),
        -2px -2px 8px rgba(255, 255, 255, 0.1);
    transform-style: preserve-3d;
    will-change: transform, left, top, opacity;
    pointer-events: auto;
    background: #f5f5f5;
    cursor: pointer;
}

.book-card:hover {
    box-shadow:
        6px 6px 25px rgba(0, 0, 0, 0.45),
        -3px -3px 12px rgba(255, 255, 255, 0.15);
    filter: brightness(1.05);
}

.book-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 8px;
    height: 100%;
    background: linear-gradient(
        90deg,
        rgba(0, 0, 0, 0.2) 0%,
        rgba(0, 0, 0, 0.1) 30%,
        rgba(255, 255, 255, 0.1) 50%,
        transparent 100%
    );
    z-index: 2;
    pointer-events: none;
}

.book-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        135deg,
        rgba(255, 255, 255, 0.15) 0%,
        transparent 50%,
        rgba(0, 0, 0, 0.05) 100%
    );
    pointer-events: none;
    z-index: 3;
}

.book-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

/* Content overlay */
.content-overlay {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 10;
    text-align: center;
    background: rgba(255, 248, 231, 0.95);
    padding: 40px 60px;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
}

.content-overlay h1 {
    font-size: 3rem;
    color: var(--text-dark);
    margin-bottom: 10px;
    background: linear-gradient(135deg, var(--accent-coral), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.content-overlay p {
    font-size: 1.2rem;
    color: var(--text-dark);
    opacity: 0.8;
}

.banner-link {
    display: inline-block;
    margin-top: 18px;
    padding: 8px 24px;
    color: var(--text-dark);
    -webkit-text-fill-color: var(--text-dark);
    text-decoration: none;
    border: 2px solid var(--text-dark);
    border-radius: 20px;
    font-weight: 600;
    font-size: 1rem;
    opacity: 0.7;
    transition: opacity 0.2s;
}

.banner-link:hover {
    opacity: 1;
}

/* Float animation keyframes */
@keyframes float {
    0%, 100% {
        transform: translateY(0) rotate(0deg);
    }
    25% {
        transform: translateY(-8px) rotate(1.5deg);
    }
    50% {
        transform: translateY(0) rotate(0deg);
    }
    75% {
        transform: translateY(8px) rotate(-1.5deg);
    }
}

.book-card.floating {
    animation: float 4s ease-in-out infinite;
}

/* Responsive breakpoints */
@media (max-width: 768px) {
    .book-card {
        width: 90px;
        height: 135px;
    }

    .content-overlay {
        padding: 25px 35px;
    }

    .content-overlay h1 {
        font-size: 2rem;
    }

    .content-overlay p {
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .book-card {
        width: 70px;
        height: 105px;
        border-radius: 3px;
    }

    .content-overlay {
        padding: 20px 25px;
        margin: 0 20px;
    }

    .content-overlay h1 {
        font-size: 1.5rem;
    }

    .content-overlay p {
        font-size: 0.9rem;
    }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    .book-card {
        animation: none !important;
        transition: none !important;
    }

    .book-card.floating {
        animation: none;
    }
}