/* Portadas automáticas profesionales V2 */
.book-cover{padding:0;background:#16233d;isolation:isolate}.book-cover>img{z-index:2}.generated-cover{position:absolute;inset:0;display:flex;flex-direction:column;align-items:flex-start;justify-content:flex-end;padding:24px 22px 28px 29px;color:#fff;text-align:left;overflow:hidden}.generated-cover[hidden]{display:none}.generated-cover:after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,transparent 22%,rgba(5,12,30,.18) 54%,rgba(5,12,30,.62));z-index:-1}.cover-spine{position:absolute;inset:0 auto 0 0;width:11px;background:linear-gradient(90deg,rgba(0,0,0,.4),rgba(255,255,255,.18),rgba(0,0,0,.15));box-shadow:4px 0 10px rgba(0,0,0,.2)}.cover-glow{position:absolute;border-radius:50%;border:22px solid rgba(255,255,255,.10);z-index:-2}.cover-glow-a{width:190px;height:190px;right:-55px;top:-55px}.cover-glow-b{width:105px;height:105px;left:22px;top:82px;border-width:12px}.cover-brand{position:absolute;left:29px;right:16px;top:20px;font:800 .63rem/1.3 'Manrope',sans-serif;letter-spacing:.105em;color:rgba(255,255,255,.85)}.cover-brand i{margin-right:5px}.cover-symbol{position:absolute;top:74px;left:29px;display:grid;place-items:center;width:66px;height:66px;border:1px solid rgba(255,255,255,.36);border-radius:20px;background:rgba(255,255,255,.16);box-shadow:0 15px 30px rgba(6,16,35,.20);backdrop-filter:blur(8px);font-size:1.8rem}.generated-cover strong{position:relative;display:block;font:900 clamp(1.05rem,1.8vw,1.45rem)/1.08 'Manrope',sans-serif;letter-spacing:-.035em;text-shadow:0 4px 16px rgba(0,0,0,.32);z-index:1}.cover-divider{width:45px;height:4px;margin:13px 0 10px;border-radius:99px;background:#fff}.generated-cover small{position:relative;font:800 .62rem/1.4 'Manrope',sans-serif;letter-spacing:.07em;color:rgba(255,255,255,.88);z-index:1}.cover-palette-1{background:linear-gradient(145deg,#0f766e,#16a085 50%,#0b3c5d)}.cover-palette-2{background:linear-gradient(145deg,#7c2d92,#6941c6 52%,#283593)}.cover-palette-3{background:linear-gradient(145deg,#b45309,#ef7d21 48%,#9f1239)}.cover-palette-4{background:linear-gradient(145deg,#1d4ed8,#2563eb 48%,#312e81)}.cover-palette-5{background:linear-gradient(145deg,#be123c,#e23d6b 48%,#7e22ce)}.cover-palette-6{background:linear-gradient(145deg,#3f6212,#65a30d 50%,#166534)}
.book-card{animation:bookEntrance .55s cubic-bezier(.22,1,.36,1) both}.book-card:nth-child(2n){animation-delay:.06s}.book-card:nth-child(3n){animation-delay:.12s}.book-card:hover .generated-cover{filter:saturate(1.08)}.book-card:hover .cover-symbol{transform:translateY(-5px) rotate(-3deg);transition:.3s}.book-actions{gap:8px;justify-content:flex-start;flex-wrap:wrap}.comment-btn{display:inline-flex;align-items:center;gap:6px;min-height:40px;padding:9px 11px;border:1px solid #d9dff0;border-radius:11px;background:#f5f2fd;color:#6941c6;font-weight:800;text-decoration:none;transition:.2s}.comment-btn:hover{background:#6941c6;border-color:#6941c6;color:#fff;text-decoration:none;transform:translateY(-2px)}.comment-btn b{display:grid;place-items:center;min-width:19px;height:19px;padding:0 5px;border-radius:99px;background:#fff;color:#6941c6;font-size:.68rem}.book-views{margin-left:auto}.featured-track .book-card{animation:featuredFloat 4.8s ease-in-out infinite}.featured-track .book-card:nth-child(2n){animation-delay:-1.6s}.featured-track .book-card:nth-child(3n){animation-delay:-3.2s}@keyframes bookEntrance{from{opacity:0;transform:translateY(22px) scale(.98)}to{opacity:1;transform:none}}@keyframes featuredFloat{0%,100%{transform:translateY(0)}50%{transform:translateY(-6px)}}
@media(max-width:680px){.generated-cover{padding:20px 15px 20px 22px}.cover-brand{left:22px;top:14px;font-size:.52rem}.cover-symbol{left:22px;top:55px;width:50px;height:50px;border-radius:15px;font-size:1.3rem}.generated-cover strong{font-size:.96rem}.generated-cover small{font-size:.52rem}.cover-glow-b{display:none}.book-actions{display:grid;grid-template-columns:1fr auto auto}.read-btn{justify-content:center}.comment-btn span{display:none}.book-views{align-self:center;margin-left:0}.featured-track .book-card{animation:none}}
@media(prefers-reduced-motion:reduce){.book-card,.featured-track .book-card{animation:none}.book-card:hover,.comment-btn:hover{transform:none}}

/* Primera página real del PDF como portada */
.book-card[data-pdf-preview] .book-cover{background:#e9edf4}
.pdf-cover-preview{position:absolute;inset:0;z-index:5;width:100%;height:100%;object-fit:cover;object-position:top center;background:#fff;opacity:0;transform:scale(1.035);filter:saturate(.94) contrast(1.02);transition:opacity .55s ease,transform .7s cubic-bezier(.2,.8,.2,1),filter .3s ease}
.pdf-preview-ready .pdf-cover-preview{opacity:1;transform:scale(1)}
.pdf-preview-ready:hover .pdf-cover-preview{transform:scale(1.035);filter:saturate(1.04) contrast(1.03)}
.pdf-cover-loading{position:absolute;left:50%;bottom:14px;z-index:7;translate:-50% 0;display:inline-flex;align-items:center;gap:7px;max-width:calc(100% - 24px);padding:7px 10px;border-radius:999px;background:#101827c9;color:#fff;font-size:.62rem;font-weight:800;white-space:nowrap;backdrop-filter:blur(8px);box-shadow:0 8px 22px #0003}
.pdf-cover-loading i{animation:pdfCoverSpin .8s linear infinite}
.pdf-preview-ready .pdf-cover-loading,.pdf-preview-failed .pdf-cover-loading{display:none}
.book-card[data-pdf-preview] .cover-grade{z-index:8;box-shadow:0 7px 20px #1018272b}
.pdf-preview-ready .generated-cover{opacity:0;transition:opacity .45s ease}
@keyframes pdfCoverSpin{to{transform:rotate(360deg)}}
@media(max-width:680px){.pdf-cover-loading{font-size:.55rem;padding:6px 8px}}
@media(prefers-reduced-motion:reduce){.pdf-cover-preview{transition:none}.pdf-cover-loading i{animation:none}}

/* Carga ligera: sin animar cientos de tarjetas a la vez. */
.book-card,.featured-track .book-card{animation:none!important}
.book-resource-tools{display:flex;align-items:center;gap:8px;flex-wrap:wrap;width:100%;min-width:0}
.book-tool-link{display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:40px;padding:9px 11px;border:1px solid #d9e8e2;border-radius:11px;background:#effaf5;color:#14765d;font-size:.78rem;font-weight:800;text-decoration:none;transition:background-color .16s ease,border-color .16s ease,color .16s ease}
.book-tool-link:hover{border-color:#16805f;background:#16805f;color:#fff;text-decoration:none}
.book-assessment-link{border-color:#ddd6fb;background:#f6f2ff;color:#6844bd}
.book-assessment-link:hover{border-color:#6844bd;background:#6844bd;color:#fff}
.book-assessment-link.is-pending{border-color:#e0e5ed;background:#f5f7fa;color:#7a8799;cursor:default;opacity:.96}
.book-assessment-link.is-pending:hover{border-color:#e0e5ed;background:#f5f7fa;color:#7a8799}
.book-views{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;margin-left:auto;padding:7px 10px;border-radius:10px;background:#f2f5f9;color:#59677e;font-size:.75rem;font-weight:800}
.book-views b{font-variant-numeric:tabular-nums}
.library-grade-context{margin:12px 0 0;padding:10px 13px;border:1px solid #cde9df;border-radius:12px;background:#effaf5;color:#17684f;font-size:.82rem;font-weight:800;line-height:1.4}
.library-grade-context[hidden]{display:none}
.book-grid[aria-busy="true"]{opacity:.72;transition:opacity .12s ease}
@media(max-width:680px){.book-actions{display:grid;grid-template-columns:1fr}.book-resource-tools{display:flex;justify-content:space-between;gap:6px}.book-tool-link,.comment-btn{min-height:38px;padding:8px 9px}.book-views{margin-left:auto}.book-resource-tools .comment-btn span{display:inline}.book-grid[aria-busy="true"]{opacity:.78}}

/* Filtros de Biblioteca por grado y tipo de material. */
.library-filter-groups{display:grid;gap:18px;margin-top:18px}.library-filter-group+.library-filter-group{padding-top:18px;border-top:1px solid #e8edf4}.library-filter-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:14px}.library-filter-label{display:inline-flex;align-items:center;gap:8px;color:#24324b;font:900 .88rem/1.2 'Manrope',sans-serif}.library-filter-label i{display:grid;place-items:center;width:28px;height:28px;border-radius:9px;background:#eef7f4;color:#16805f;font-size:.78rem}.library-filter-heading small{display:block;margin:5px 0 0;color:#738098;font-size:.76rem;line-height:1.35}.filter-pills.grade-pills,.filter-pills.material-pills{display:grid;gap:10px;overflow:visible;padding:13px 0 0}.filter-pills.grade-pills{grid-template-columns:repeat(6,minmax(0,1fr))}.filter-pills.material-pills{grid-template-columns:repeat(4,minmax(0,1fr))}.filter-pills button.filter-pill{display:flex;align-items:center;justify-content:center;gap:8px;min-height:62px;padding:9px 8px;border:1px solid #dce5ef;border-radius:15px;background:#fbfcfe;color:#36445b;font-size:.76rem;font-weight:900;line-height:1.16;text-align:left;white-space:normal;box-shadow:0 5px 14px #24324b08;transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease,background-color .18s ease,color .18s ease}.filter-pills button.filter-pill:hover:not(:disabled){transform:translateY(-2px);border-color:#afc9bd;background:#f4fbf8;box-shadow:0 10px 22px #24324b12}.filter-pills button.filter-pill:focus-visible{outline:3px solid #87d4bc;outline-offset:2px}.filter-pill-icon{display:grid;place-items:center;flex:0 0 30px;width:30px;height:30px;border-radius:10px;background:#eaf0f7;color:#526078;font-size:.82rem}.filter-pills button.grade-all .filter-pill-icon{background:#e8eef7;color:#43536d}.filter-pills button.grade-one .filter-pill-icon{background:#e5f8ec;color:#198359}.filter-pills button.grade-two .filter-pill-icon{background:#e8f3ff;color:#2d73b8}.filter-pills button.grade-three .filter-pill-icon{background:#fff1dc;color:#bd7214}.filter-pills button.grade-four .filter-pill-icon{background:#f2eaff;color:#7450b7}.filter-pills button.grade-five .filter-pill-icon{background:#fbe8ee;color:#bd4564}.filter-pills button.material-reading .filter-pill-icon{background:#e6f8f0;color:#16805f}.filter-pills button.material-textbook .filter-pill-icon{background:#e9edff;color:#4e58ba}.filter-pills button.material-minedu .filter-pill-icon{background:#fff1dc;color:#b96d13}.filter-pills button.material-sheet .filter-pill-icon{background:#f4eafe;color:#7b4bb9}.filter-pills button.filter-pill.active{border-color:#16805f;background:linear-gradient(135deg,#11775a,#1c9f78);color:#fff;box-shadow:0 11px 25px #16805f35}.filter-pills button.filter-pill.active .filter-pill-icon{background:#ffffff24;color:#fff}.filter-pills button.filter-pill:disabled{cursor:default;opacity:1}.material-filter-group .library-filter-label i{background:#f1ecff;color:#7048b7}.library-grade-context{display:flex;align-items:center;gap:8px;margin:13px 0 0}.library-grade-context:before{content:'\f00c';font-family:'Font Awesome 5 Free';font-weight:900;display:grid;place-items:center;width:22px;height:22px;border-radius:50%;background:#16805f;color:#fff;font-size:.65rem}.library-grade-context[hidden]{display:none}
@media(max-width:860px){.filter-pills.grade-pills{grid-template-columns:repeat(3,minmax(0,1fr))}.filter-pills.material-pills{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:480px){.library-filter-groups{gap:15px;margin-top:15px}.library-filter-group+.library-filter-group{padding-top:15px}.filter-pills.grade-pills{grid-template-columns:repeat(2,minmax(0,1fr))}.filter-pills.material-pills{grid-template-columns:repeat(2,minmax(0,1fr))}.filter-pills button.filter-pill{min-height:54px;padding:8px 7px;border-radius:13px;font-size:.7rem}.filter-pill-icon{flex-basis:26px;width:26px;height:26px;border-radius:8px;font-size:.72rem}.library-filter-heading small{font-size:.69rem}.library-filter-label{font-size:.8rem}}
@media(prefers-reduced-motion:reduce){.filter-pills button.filter-pill{transition:none}.filter-pills button.filter-pill:hover:not(:disabled){transform:none}}