body {
    font-family: 'Inter', sans-serif;
    margin: 0;
    user-select: none;
    background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
    min-height: 100vh;
    background-image: url('https://images.unsplash.com/photo-1481627834876-b7833e8f5570?fm=jpg&q=60&w=3000&ixlib=rb-4.1.0&ixid=M3wxMjA3fDB8MHxzZWFyY2h8M3x8bGlicmFyeXxlbnwwfHwwfHx8MA%3D%3D');
    background-size: cover;
    background-repeat: no-repeat;
}

.glass-panel {
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    border-radius: 16px;
}

.screen {
    display: none;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.5s ease;
}

.screen.active {
    opacity: 1;
    transform: translateY(0);
}

.book-option {
    transition: all 0.3s ease;
}

.book-option:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3);
}

.floating {
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
    100% { transform: translateY(0px); }
}

.pulse {
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(79, 70, 229, 0.7); }
    70% { box-shadow: 0 0 0 10px rgba(79, 70, 229, 0); }
    100% { box-shadow: 0 0 0 0 rgba(79, 70, 229, 0); }
}

.book-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
    max-height: 60vh;
    overflow-y: auto;
    padding: 10px;
}

.exit-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 100;
    background: rgba(239, 68, 68, 0.9);
    color: white;
    border: none;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.4);
    transition: all 0.3s ease;
}

.exit-btn:hover {
    background: rgba(239, 68, 68, 1);
    transform: scale(1.1);
}

.hidden {
    display: none !important;
}