:root {
    --bg-base: #09090b;
    --bg-surface: #121215;
    --bg-surface-hover: #1e1e22;
    --accent: #8b5cf6;
    --text-primary: #ffffff;
    --text-secondary: #a1a1aa;
    --radius-md: 12px;
    --radius-lg: 24px;
    --radius-full: 9999px;
    --glass-border: 1px solid rgba(255, 255, 255, 0.1);
    --glass-bg: rgba(20, 20, 23, 0.7);
    --nav-height: 80px;
}

* { box-sizing: border-box; outline: none; }

body {
    margin: 0;
    background-color: var(--bg-base);
    color: var(--text-primary);
    font-family: 'Inter', system-ui, sans-serif;
    overflow-x: hidden;
}

.back-btn {
    position: fixed;
    top: 2rem; left: 2rem; z-index: 100;
    display: flex; align-items: center; gap: 0.5rem;
    padding: 0.8rem 1.5rem;
    background: var(--glass-bg); backdrop-filter: blur(12px);
    border: var(--glass-border); border-radius: var(--radius-full);
    color: white; text-decoration: none; font-weight: 600;
    transition: all 0.2s ease;
}
.back-btn:hover { background: rgba(255, 255, 255, 0.15); transform: translateX(-5px); }

.hero-wrapper {
    position: relative; width: 100%; height: 60vh; overflow: hidden;
}
.hero-background { position: absolute; inset: 0; z-index: 0; }
.hero-background img { width: 100%; height: 100%; object-fit: cover; opacity: 0.4; filter: blur(8px); transform: scale(1.1); }
.hero-overlay {
    position: absolute; inset: 0; z-index: 1;
    background: linear-gradient(to bottom, transparent 0%, var(--bg-base) 100%);
}

.content-container {
    position: relative; z-index: 10;
    max-width: 1600px; margin: -350px auto 0 auto;
    padding: 0 3rem 4rem 3rem;
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 3rem;
    align-items: flex-start;
    animation: slideUp 0.8s ease;
}

.hero-content { display: none; }

.sidebar {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    position: sticky;
    top: calc(var(--nav-height) + 2rem);
    align-self: flex-start;
    z-index: 20;
}

.poster-card {
    width: 100%; aspect-ratio: 2/3; border-radius: var(--radius-lg);
    overflow: hidden; box-shadow: 0 25px 50px -12px rgba(0,0,0,0.8);
    border: 1px solid rgba(255,255,255,0.1);
    background: #1a1a1a;
}
.poster-card img { width: 100%; height: 100%; object-fit: cover; }

.info-grid {
    background: var(--bg-surface); border: var(--glass-border);
    border-radius: var(--radius-md); padding: 1.25rem;
    display: flex; flex-direction: column; gap: 1rem;
}
.info-item h4 { margin: 0 0 0.25rem 0; font-size: 0.8rem; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 0.5px; }
.info-item span { font-weight: 600; font-size: 0.95rem; }

.main-content {
    display: flex; flex-direction: column;
    padding-top: 4rem;
    justify-content: flex-start;
}

.book-header { margin-bottom: 1.5rem; }
.book-title { font-size: 3.5rem; font-weight: 900; line-height: 1.1; margin: 0 0 1rem 0; text-shadow: 0 4px 30px rgba(0,0,0,0.8); }

.meta-row { display: flex; align-items: center; gap: 1rem; margin-bottom: 1.5rem; flex-wrap: wrap; }
.pill { padding: 0.4rem 1rem; background: rgba(255,255,255,0.1); border-radius: 99px; font-size: 0.9rem; font-weight: 600; border: var(--glass-border); backdrop-filter: blur(10px); }
.pill.score { background: rgba(34, 197, 94, 0.2); color: #4ade80; border-color: rgba(34, 197, 94, 0.2); }

#description { display: none; }
#year { display: none; }

.action-row { display: flex; gap: 1rem; }
.btn-primary {
    padding: 0.8rem 2rem; background: white; color: black; border: none; border-radius: 99px;
    font-weight: 800; cursor: pointer; transition: transform 0.2s;
}
.btn-primary:hover { transform: scale(1.05); }

.btn-secondary {
    padding: 0.8rem 2rem;
    background: rgba(255,255,255,0.1);
    color: white;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 99px;
    font-weight: 700;
    cursor: pointer;
    transition: 0.2s;
    backdrop-filter: blur(10px);
}
.btn-secondary:hover {
    background: rgba(255,255,255,0.2);
}

.btn-blur {
    padding: 0.8rem 2rem;
    background: rgba(255,255,255,0.1);
    color: white;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 99px;
    font-weight: 700;
    cursor: pointer;
    transition: 0.2s;
    backdrop-filter: blur(10px);
}
.btn-blur:hover { background: rgba(255,255,255,0.2); }

.chapters-section { margin-top: 1rem; }
.section-title { display: flex; align-items: center; border-bottom: 1px solid rgba(255,255,255,0.1); padding-bottom: 0.8rem; margin-bottom: 1.5rem; }
.section-title h2 { font-size: 1.5rem; margin: 0; border-left: 4px solid var(--accent); padding-left: 1rem; }

.chapters-table-wrapper {
    background: var(--bg-surface); border-radius: var(--radius-md);
    border: 1px solid rgba(255,255,255,0.05); overflow: hidden;
}
.chapters-table { width: 100%; border-collapse: collapse; text-align: left; }
.chapters-table th {
    padding: 0.8rem 1.2rem; background: rgba(255,255,255,0.03);
    color: var(--text-secondary); font-weight: 600; font-size: 0.85rem;
    text-transform: uppercase; letter-spacing: 0.5px;
}
.chapters-table td {
    padding: 1rem 1.2rem; border-bottom: 1px solid rgba(255,255,255,0.05);
    color: var(--text-primary); font-size: 0.95rem;
}
.chapters-table tr:last-child td { border-bottom: none; }
.chapters-table tr:hover { background: var(--bg-surface-hover); }

.filter-select {
    appearance: none;
    -webkit-appearance: none;
    background-color: var(--bg-surface);
    color: var(--text-primary);
    border: 1px solid rgba(255,255,255,0.1);
    padding: 0.5rem 2rem 0.5rem 1rem;
    border-radius: 99px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    outline: none;
    background-image: url("data:image/svg+xml,%3Csvg width='10' height='6' viewBox='0 0 10 6' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1L5 5L9 1' stroke='white' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
}

.filter-select:hover {
    border-color: var(--accent);
    background-color: var(--bg-surface-hover);
}

.filter-select option {
    background-color: var(--bg-surface);
    color: var(--text-primary);
}

.read-btn-small {
    background: var(--accent); color: white; border: none;
    padding: 0.4rem 0.9rem; border-radius: 6px; font-weight: 600; cursor: pointer;
    font-size: 0.8rem; transition: 0.2s;
}
.read-btn-small:hover { background: #7c3aed; }

.pagination-controls {
    display: flex; justify-content: center; gap: 1rem; margin-top: 1.5rem; align-items: center;
}
.page-btn {
    background: var(--bg-surface); border: 1px solid rgba(255,255,255,0.1);
    color: white; padding: 0.5rem 1rem; border-radius: 8px; cursor: pointer; font-size: 0.9rem;
}
.page-btn:disabled { opacity: 0.5; cursor: not-allowed; }
.page-btn:hover:not(:disabled) { border-color: var(--accent); }

@keyframes slideUp { from { opacity: 0; transform: translateY(40px); } to { opacity: 1; transform: translateY(0); } }

@media (max-width: 1024px) {
    .hero-wrapper { height: 40vh; }
    .content-container { grid-template-columns: 1fr; margin-top: -80px; padding: 0 1.5rem 4rem 1.5rem; }
    .poster-card { display: none; }

    .main-content { padding-top: 0; align-items: center; text-align: center; }
    .book-title { font-size: 2.2rem; }
    .meta-row { justify-content: center; }
    .action-row { justify-content: center; width: 100%; }
    .btn-primary, .btn-blur { flex: 1; justify-content: center; }

    .sidebar { display: none; }
    .chapters-table th:nth-child(3), .chapters-table td:nth-child(3) { display: none; }
    .chapters-table th:nth-child(4), .chapters-table td:nth-child(4) { display: none; }
}

/* ==================================== */
/* MODAL STYLES (Add to Library Modal)  */
/* ==================================== */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(8px);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s;
    padding: 2rem;
}
.modal-overlay.active {
    display: flex;
    opacity: 1;
}
.modal-content {
    background: #18181b;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 24px;
    padding: 2.5rem;
    max-width: 650px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    position: relative;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    transform: scale(0.95);
    transition: transform 0.3s;
}
.modal-overlay.active .modal-content {
    transform: scale(1);
}

.modal-content.modal-list {
    max-width: 500px;
}

.modal-close {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    color: white;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: 0.2s;
}
.modal-close:hover { background: rgba(255, 255, 255, 0.2); }
.modal-title { margin-top: 0; margin-bottom: 1.5rem; font-size: 1.5rem; font-weight: 800; }

.modal-body {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-input {
    background: var(--bg-base);
    border: 1px solid rgba(255,255,255,0.1);
    color: var(--text-primary);
    padding: 0.8rem 1rem;
    border-radius: 8px;
    font-family: inherit;
    font-size: 1rem;
    transition: 0.2s;
}

.form-input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 10px rgba(139, 92, 246, 0.4); /* Usar el color acento */
}

.modal-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.btn-modal-primary, .btn-modal-secondary, .btn-modal-danger {
    padding: 0.8rem 1.5rem;
    border-radius: 999px;
    font-weight: 700;
    font-size: 0.95rem;
    border: none;
    cursor: pointer;
    transition: transform 0.2s, opacity 0.2s;
    flex: 1;
}

.btn-modal-primary {
    background: var(--accent);
    color: white;
}

.btn-modal-primary:hover {
    transform: scale(1.05);
}

.btn-modal-secondary {
    background: rgba(255,255,255,0.1);
    color: white;
    border: 1px solid rgba(255,255,255,0.2);
}

.btn-modal-secondary:hover {
    background: rgba(255,255,255,0.15);
}

.btn-modal-danger {
    background: #ef4444; /* Usar el color danger */
    color: white;
}

.btn-modal-danger:hover {
    opacity: 0.9;
}