*,
    *::before,
    *::after {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    :root {
      /* Paleta principal — luminosa y fresca */
      --cream: #FDFAF5;
      --cream-dark: #F4EFE4;
      --white: #FFFFFF;

      /* Verde bosque */
      --green: #2A6B47;
      --green-mid: #3D8C5F;
      --green-light: #5AAD7A;
      --green-pale: #EBF5EF;
      --green-faint: #F2FAF5;

      /* Ámbar cálido */
      --amber: #C47C2B;
      --amber-light: #E8A645;
      --amber-pale: #FEF7EC;

      /* Texto */
      --text-heading: #1A2218;
      --text-main: #2C3329;
      --text-muted: #62796B;
      --text-light: #94A89C;

      /* Bordes y sombras */
      --border: #E0DAD0;
      --border-light: #EDE8DF;
      --shadow-sm: 0 2px 8px rgba(30, 60, 40, .07);
      --shadow-md: 0 8px 24px rgba(30, 60, 40, .10);
      --shadow-lg: 0 20px 48px rgba(30, 60, 40, .13);

      /* Radios */
      --radius: 12px;
      --radius-lg: 20px;
      --radius-xl: 28px;
    }

    body {
      font-family: 'Inter', sans-serif;
      background: var(--cream);
      color: var(--text-main);
      font-size: 15px;
      overflow-x: hidden;
      -webkit-font-smoothing: antialiased;
      letter-spacing: -0.01em;
    }

    h1,
    h2,
    h3,
    h4 {
      font-family: 'Plus Jakarta Sans', sans-serif;
      color: var(--text-heading);
      font-weight: 700;
    }

    /* ── NAVBAR ─────────────────────────────────────────────────── */
    nav {
      background: var(--white);
      border-bottom: 1px solid var(--border-light);
      padding: 0 80px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 68px;
      position: sticky;
      top: 0;
      z-index: 100;
      box-shadow: var(--shadow-sm);
    }

    .logo {
      cursor: pointer;
      display: flex;
      align-items: center;
      flex-shrink: 0;
    }

    .logo img {
      height: 40px;
      /* 887×180 → ~4.9:1 ratio → width ≈ 196px */
      width: auto;
      display: block;
    }

    .logo-leaf {
      display: none;
    }

    .nav-links {
      display: flex;
      gap: 32px;
      list-style: none;
    }

    .nav-links a {
      color: var(--text-muted);
      font-size: 14px;
      font-weight: 500;
      text-decoration: none;
      cursor: pointer;
      transition: color .2s;
      padding: 4px 0;
      border-bottom: 2px solid transparent;
    }

    .nav-links a:hover {
      color: var(--green);
      border-bottom-color: var(--green);
    }

    .nav-right {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .btn-nav {
      background: transparent;
      border: 1.5px solid var(--border);
      color: var(--text-main);
      padding: 8px 18px;
      border-radius: 10px;
      font-size: 13px;
      font-weight: 500;
      cursor: pointer;
      font-family: 'Inter', sans-serif;
      transition: all .2s;
    }

    .btn-nav:hover {
      border-color: var(--green);
      color: var(--green);
    }

    .btn-sell {
      background: var(--green);
      border: none;
      color: var(--white);
      padding: 9px 20px;
      border-radius: 10px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      font-family: 'Inter', sans-serif;
      transition: all .2s;
      box-shadow: 0 2px 8px rgba(42, 107, 71, .25);
    }

    .btn-sell:hover {
      background: var(--green-mid);
      transform: translateY(-1px);
      box-shadow: 0 4px 12px rgba(42, 107, 71, .3);
    }

    .cart-btn {
      position: relative;
      background: var(--amber-pale);
      border: 1.5px solid #F2C27A;
      color: var(--amber);
      width: 44px;
      height: 44px;
      border-radius: 12px;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 18px;
      transition: all .2s;
    }

    .cart-btn:hover {
      background: var(--amber);
      color: white;
      border-color: var(--amber);
    }

    .cart-badge {
      position: absolute;
      top: -7px;
      right: -7px;
      background: var(--green);
      color: white;
      width: 20px;
      height: 20px;
      border-radius: 50%;
      font-size: 10px;
      font-weight: 600;
      display: flex;
      align-items: center;
      justify-content: center;
      font-family: 'Inter', sans-serif;
      border: 2px solid white;
    }

    /* ── PAGES ──────────────────────────────────────────────────── */
    .page {
      display: none;
      animation: fadeIn .35s ease;
    }

    .page.active {
      display: block;
    }

    @keyframes fadeIn {
      from {
        opacity: 0;
        transform: translateY(10px);
      }

      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    /* ── HERO ───────────────────────────────────────────────────── */
    .hero {
      background: linear-gradient(135deg, #EDF7F1 0%, #F9F6EF 50%, #EBF3EF 100%);
      padding: 80px 80px 72px;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
      overflow: hidden;
      position: relative;
      border-bottom: 1px solid var(--border-light);
    }

    .hero::before {
      content: '';
      position: absolute;
      right: -60px;
      top: -60px;
      width: 380px;
      height: 380px;
      background: radial-gradient(circle, rgba(90, 173, 122, .18) 0%, transparent 70%);
      pointer-events: none;
    }

    .hero::after {
      content: '';
      position: absolute;
      left: 40%;
      bottom: -80px;
      width: 260px;
      height: 260px;
      background: radial-gradient(circle, rgba(232, 166, 69, .14) 0%, transparent 70%);
      pointer-events: none;
    }

    .hero-tag {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: var(--green-pale);
      border: 1px solid rgba(42, 107, 71, .2);
      color: var(--green);
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 600;
      margin-bottom: 22px;
      letter-spacing: .4px;
    }

    .hero h1 {
      font-size: 54px;
      color: var(--text-heading);
      line-height: 1.08;
      letter-spacing: -1.5px;
      margin-bottom: 20px;
      font-weight: 700;
    }

    .hero h1 em {
      color: var(--green);
      font-style: italic;
      font-weight: 300;
    }

    .hero>div>p {
      color: var(--text-muted);
      font-size: 16px;
      line-height: 1.75;
      margin-bottom: 36px;
      max-width: 440px;
    }

    .hero-btns {
      display: flex;
      gap: 12px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--green);
      border: none;
      color: var(--white);
      padding: 14px 30px;
      border-radius: 12px;
      font-size: 15px;
      font-weight: 600;
      cursor: pointer;
      font-family: 'Inter', sans-serif;
      transition: all .25s;
      box-shadow: 0 4px 14px rgba(42, 107, 71, .28);
    }

    .btn-primary:hover {
      background: var(--green-mid);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(42, 107, 71, .32);
    }

    .btn-outline {
      background: var(--white);
      border: 1.5px solid var(--border);
      color: var(--text-main);
      padding: 14px 28px;
      border-radius: 12px;
      font-size: 15px;
      font-weight: 500;
      cursor: pointer;
      font-family: 'Inter', sans-serif;
      transition: all .25s;
    }

    .btn-outline:hover {
      border-color: var(--green);
      color: var(--green);
      background: var(--green-faint);
    }

    .hero-stats {
      display: flex;
      gap: 36px;
      margin-top: 44px;
    }

    .stat-item {
      text-align: left;
    }

    .stat-num {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 30px;
      color: var(--green);
      font-weight: 800;
      line-height: 1;
    }

    .stat-label {
      font-size: 12px;
      color: var(--text-muted);
      margin-top: 5px;
      font-weight: 500;
    }

    /* ── HERO VISUAL ─────────────────────────────────────────────── */
    .hero-visual {
      position: relative;
      z-index: 1;
      display: flex;
      justify-content: center;
      align-items: center;
    }

    .book-stack {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 14px;
      transform: perspective(700px) rotateY(-6deg) rotateX(3deg);
      max-width: 340px;
      filter: drop-shadow(0 24px 40px rgba(30, 60, 40, .14));
    }

    .book-card-mini {
      border-radius: 14px;
      padding: 18px 16px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      height: 140px;
      cursor: pointer;
      transition: transform .3s, box-shadow .3s;
      box-shadow: 0 4px 16px rgba(0, 0, 0, .12);
    }

    .book-card-mini:hover {
      transform: translateY(-6px) scale(1.04);
      box-shadow: 0 12px 28px rgba(0, 0, 0, .18);
    }

    .bcm-1 {
      background: linear-gradient(145deg, #2A6B47, #3D8C5F);
      grid-column: span 2;
    }

    .bcm-2 {
      background: linear-gradient(145deg, #1A3D2C, #2A6B47);
    }

    .bcm-3 {
      background: linear-gradient(145deg, #C47C2B, #E8A645);
    }

    .bcm-4 {
      background: linear-gradient(145deg, #5A3A20, #8A5C34);
    }

    .bcm-5 {
      background: linear-gradient(145deg, #1C3F5A, #2B6080);
      grid-column: span 2;
    }

    .bcm-6 {
      background: linear-gradient(145deg, #4A1860, #7A3498);
    }

    .book-card-mini .subject {
      font-size: 9px;
      color: rgba(255, 255, 255, .6);
      text-transform: uppercase;
      letter-spacing: 1px;
      font-weight: 600;
    }

    .book-card-mini .title {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 13px;
      font-weight: 600;
      color: rgba(255, 255, 255, .95);
      line-height: 1.3;
      margin-top: 5px;
    }

    .book-card-mini .price {
      font-size: 13px;
      font-weight: 600;
      color: var(--amber-light);
    }

    /* ── SEARCH BAR ─────────────────────────────────────────────── */
    .search-section {
      padding: 36px 80px;
      background: var(--white);
      border-bottom: 1px solid var(--border-light);
    }

    .search-wrap {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      gap: 10px;
      flex-wrap: wrap;
      justify-content: center;
    }

    .search-input {
      flex: 1;
      background: var(--cream);
      border: 1.5px solid var(--border);
      border-radius: 12px;
      padding: 13px 20px;
      font-size: 15px;
      font-family: 'Inter', sans-serif;
      color: var(--text-main);
      outline: none;
      transition: border .2s, box-shadow .2s;
    }

    .search-input:focus {
      border-color: var(--green);
      box-shadow: 0 0 0 3px rgba(42, 107, 71, .1);
    }

    .search-input::placeholder {
      color: var(--text-light);
    }

    .filter-select {
      background: var(--cream);
      border: 1.5px solid var(--border);
      border-radius: 12px;
      padding: 13px 16px;
      font-size: 14px;
      font-family: 'Inter', sans-serif;
      color: var(--text-main);
      cursor: pointer;
      outline: none;
      transition: border .2s;
      flex: 1 1 180px;
      min-width: 140px;
    }

    .filter-select:focus {
      border-color: var(--green);
    }

    .btn-search {
      background: var(--green);
      border: none;
      color: white;
      padding: 13px 26px;
      border-radius: 12px;
      font-size: 14px;
      font-weight: 600;
      cursor: pointer;
      font-family: 'Inter', sans-serif;
      white-space: nowrap;
      transition: all .2s;
      box-shadow: 0 2px 8px rgba(42, 107, 71, .22);
    }

    .btn-search:hover {
      background: var(--green-mid);
    }

    /* ── FILTER PILLS ───────────────────────────────────────────── */
    .filters-row {
      padding: 18px 80px;
      display: flex;
      gap: 8px;
      overflow-x: auto;
      background: var(--white);
      border-bottom: 1px solid var(--border-light);
      scrollbar-width: none;
    }

    .filters-row::-webkit-scrollbar {
      display: none;
    }

    .pill {
      background: var(--cream);
      border: 1.5px solid var(--border);
      color: var(--text-muted);
      padding: 7px 18px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 500;
      cursor: pointer;
      white-space: nowrap;
      transition: all .2s;
      font-family: 'Inter', sans-serif;
    }

    .pill:hover {
      border-color: var(--green);
      color: var(--green);
      background: var(--green-faint);
    }

    .pill.active {
      background: var(--green);
      border-color: var(--green);
      color: var(--white);
      box-shadow: 0 2px 8px rgba(42, 107, 71, .22);
    }

    /* ── BOOKS SECTION ─────────────────────────────────────────── */
    .section {
      padding: 48px 80px;
      background: var(--cream);
    }

    .section-header {
      display: flex;
      justify-content: space-between;
      align-items: baseline;
      margin-bottom: 32px;
    }

    .section-title {
      font-size: 30px;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--text-heading);
    }

    .section-title span {
      color: var(--green);
    }

    .see-all {
      font-size: 13px;
      color: var(--green);
      cursor: pointer;
      text-decoration: none;
      font-weight: 600;
      display: flex;
      align-items: center;
      gap: 4px;
    }

    .see-all:hover {
      text-decoration: underline;
    }

    /* ── BOOK CARDS ─────────────────────────────────────────────── */
    .books-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
      gap: 22px;
    }

    .book-card {
      background: var(--white);
      border-radius: var(--radius-xl);
      border: 1px solid var(--border-light);
      overflow: hidden;
      cursor: pointer;
      transition: all .28s cubic-bezier(.34, 1.56, .64, 1);
      display: flex;
      flex-direction: column;
      box-shadow: var(--shadow-sm);
    }

    .book-card:hover {
      transform: translateY(-6px);
      border-color: var(--green);
      box-shadow: 0 16px 40px rgba(42, 107, 71, .14);
    }

    .book-cover {
      height: 170px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 44px;
      position: relative;
      flex-shrink: 0;
    }

    /* Colores de portada más vivos */
    .cover-mat {
      background: linear-gradient(145deg, #1E5C3A, #2E8B56);
    }

    .cover-cien {
      background: linear-gradient(145deg, #1A3D60, #2B6CB0);
    }

    .cover-len {
      background: linear-gradient(145deg, #5C2A1A, #9A4E28);
    }

    .cover-hist {
      background: linear-gradient(145deg, #6B3A1A, #B06030);
    }

    .cover-ing {
      background: linear-gradient(145deg, #1A3A60, #265C90);
    }

    .cover-arte {
      background: linear-gradient(145deg, #5C1A4A, #9A2A78);
    }

    .cover-quim {
      background: linear-gradient(145deg, #1A4A5C, #2A7A96);
    }

    .cover-bio {
      background: linear-gradient(145deg, #2D4A1A, #4E7C2A);
    }

    .book-grade-badge {
      position: absolute;
      top: 12px;
      right: 12px;
      background: rgba(0, 0, 0, .30);
      backdrop-filter: blur(4px);
      color: white;
      font-size: 10px;
      padding: 4px 10px;
      border-radius: 20px;
      font-family: 'Inter', sans-serif;
      font-weight: 600;
      letter-spacing: .3px;
    }

    .book-cond-badge {
      position: absolute;
      top: 12px;
      left: 12px;
      font-size: 10px;
      padding: 4px 10px;
      border-radius: 20px;
      font-family: 'Inter', sans-serif;
      font-weight: 600;
    }

    .cond-good {
      background: rgba(235, 245, 239, .95);
      color: #2A6B47;
    }

    .cond-used {
      background: rgba(254, 247, 236, .95);
      color: #C47C2B;
    }

    .cond-wear {
      background: rgba(253, 234, 232, .95);
      color: #C0392B;
    }

    .book-info {
      padding: 16px 18px;
      flex: 1;
      display: flex;
      flex-direction: column;
    }

    .book-subject {
      font-size: 10px;
      color: var(--green);
      text-transform: uppercase;
      letter-spacing: .8px;
      font-weight: 700;
      margin-bottom: 5px;
      background: var(--green-pale);
      display: inline-block;
      padding: 2px 8px;
      border-radius: 4px;
    }

    .book-title {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 15px;
      font-weight: 600;
      line-height: 1.35;
      margin-bottom: 6px;
      flex: 1;
      color: var(--text-heading);
    }

    .book-meta {
      font-size: 12px;
      color: var(--text-light);
      margin-bottom: 14px;
    }

    .book-footer {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .book-price {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 21px;
      color: var(--green);
      font-weight: 800;
    }

    .book-price span {
      font-size: 11px;
      color: var(--text-light);
      font-family: 'Inter', sans-serif;
      font-weight: 400;
    }

    .add-cart-btn {
      background: var(--green);
      border: none;
      color: white;
      width: 36px;
      height: 36px;
      border-radius: 10px;
      cursor: pointer;
      font-size: 18px;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all .2s;
      flex-shrink: 0;
      box-shadow: 0 2px 8px rgba(42, 107, 71, .25);
    }

    .add-cart-btn:hover {
      background: var(--green-mid);
      transform: scale(1.1);
    }

    .add-cart-btn.added {
      background: var(--amber);
    }

    /* ── HOW IT WORKS ─────────────────────────────────────────── */
    .how-section {
      padding: 72px 80px;
      background: var(--cream);
      border-top: 1px solid var(--border-light);
      border-bottom: 1px solid var(--border-light);
      position: relative;
      overflow: hidden;
    }

    .how-section::before {
      content: '';
      position: absolute;
      top: -80px;
      right: -80px;
      width: 360px;
      height: 360px;
      background: radial-gradient(circle, rgba(42, 107, 71, .07) 0%, transparent 70%);
      pointer-events: none;
    }

    .how-section .section-title {
      color: var(--text-heading);
    }

    .how-section .section-title span {
      color: var(--green);
    }

    .steps-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      margin-top: 48px;
    }

    .step-card {
      text-align: center;
      padding: 32px 24px;
      background: var(--white);
      border: 1.5px solid var(--border-light);
      border-radius: var(--radius-lg);
      transition: all .28s cubic-bezier(.34, 1.56, .64, 1);
      box-shadow: var(--shadow-sm);
    }

    .step-card:hover {
      transform: translateY(-6px);
      border-color: var(--green);
      box-shadow: 0 16px 40px rgba(42, 107, 71, .12);
    }

    .step-icon {
      width: 60px;
      height: 60px;
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 24px;
      margin: 0 auto 18px;
    }

    .si-1 {
      background: var(--green-pale);
    }

    .si-2 {
      background: var(--amber-pale);
    }

    .si-3 {
      background: #EBF2FA;
    }

    .si-4 {
      background: var(--green-pale);
    }

    .step-num {
      font-size: 10px;
      color: var(--green);
      letter-spacing: 1.2px;
      text-transform: uppercase;
      margin-bottom: 10px;
      font-weight: 700;
    }

    .step-title {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 17px;
      font-weight: 700;
      color: var(--text-heading);
      margin-bottom: 10px;
    }

    .step-desc {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.75;
    }

    /* ── ECO BANNER ──────────────────────────────────────────── */
    .eco-banner {
      background: linear-gradient(135deg, #2A6B47 0%, #1E8C5A 50%, #3AAD6F 100%);
      padding: 60px 80px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      position: relative;
      overflow: hidden;
    }

    .eco-banner::before {
      content: '';
      position: absolute;
      top: -50px;
      right: 20%;
      width: 300px;
      height: 300px;
      background: radial-gradient(circle, rgba(255, 255, 255, .08) 0%, transparent 70%);
      pointer-events: none;
    }

    .eco-text h2 {
      font-size: 32px;
      color: var(--white);
      letter-spacing: -0.5px;
      margin-bottom: 10px;
    }

    .eco-text p {
      color: rgba(255, 255, 255, .75);
      font-size: 15px;
      max-width: 480px;
      line-height: 1.7;
    }

    .eco-numbers {
      display: flex;
      gap: 48px;
      flex-shrink: 0;
    }

    .eco-num {
      text-align: center;
    }

    .eco-num .num {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 40px;
      color: var(--amber-light);
      font-weight: 800;
      line-height: 1;
    }

    .eco-num .label {
      font-size: 12px;
      color: rgba(255, 255, 255, .65);
      margin-top: 6px;
      font-weight: 500;
    }

    .eco-divider {
      width: 1px;
      background: rgba(255, 255, 255, .2);
    }

    /* ── FOOTER ──────────────────────────────────────────────── */
    footer {
      background: #FFFFFF;
      border-top: 1px solid var(--border);
      padding: 56px 80px 32px;
      color: var(--text-muted);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 48px;
      margin-bottom: 48px;
    }

    .footer-brand .logo {
      font-size: 22px;
      margin-bottom: 14px;
      display: flex;
      color: var(--green-light);
    }

    .footer-brand .logo span {
      color: var(--amber-light);
    }

    .footer-brand p {
      font-size: 13px;
      line-height: 1.8;
      max-width: 280px;
      color: var(--text-muted);
    }

    .footer-col h4 {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 12px;
      color: var(--text-heading);
      margin-bottom: 16px;
      font-weight: 700;
      letter-spacing: .06em;
      text-transform: uppercase;
    }

    .footer-col a {
      display: block;
      font-size: 13px;
      color: var(--text-muted);
      text-decoration: none;
      margin-bottom: 10px;
      cursor: pointer;
      transition: color .2s;
    }

    .footer-col a:hover {
      color: var(--green);
    }

    .footer-bottom {
      border-top: 1px solid var(--border);
      padding-top: 24px;
      display: flex;
      justify-content: space-between;
      font-size: 12px;
      color: var(--text-light);
    }

    /* ── CART PAGE ──────────────────────────────────────────── */
    .cart-page {
      padding: 48px 80px;
      max-width: 1100px;
      margin: 0 auto;
    }

    .cart-page h2 {
      font-size: 34px;
      letter-spacing: -.5px;
      margin-bottom: 8px;
      color: var(--text-heading);
    }

    .cart-page h2 span {
      color: var(--green);
    }

    .cart-subtitle {
      color: var(--text-muted);
      font-size: 14px;
      margin-bottom: 40px;
    }

    .cart-layout {
      display: grid;
      grid-template-columns: 1fr 360px;
      gap: 28px;
      align-items: start;
    }

    .cart-items {
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .cart-item {
      background: var(--white);
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-light);
      padding: 20px 24px;
      display: flex;
      gap: 18px;
      align-items: center;
      transition: all .2s;
      box-shadow: var(--shadow-sm);
    }

    .cart-item:hover {
      border-color: var(--green);
      box-shadow: var(--shadow-md);
    }

    .cart-item-cover {
      width: 68px;
      height: 84px;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 28px;
      flex-shrink: 0;
    }

    .cart-item-info {
      flex: 1;
    }

    .cart-item-subj {
      font-size: 10px;
      color: var(--green);
      text-transform: uppercase;
      letter-spacing: .8px;
      font-weight: 700;
      margin-bottom: 4px;
    }

    .cart-item-title {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 16px;
      font-weight: 600;
      margin-bottom: 5px;
      color: var(--text-heading);
    }

    .cart-item-meta {
      font-size: 12px;
      color: var(--text-light);
      margin-bottom: 8px;
    }

    .cart-item-cond {
      display: inline-block;
      font-size: 11px;
      padding: 3px 10px;
      border-radius: 12px;
      font-weight: 600;
    }

    .cart-item-price {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 24px;
      color: var(--green);
      font-weight: 800;
      margin-right: 16px;
      white-space: nowrap;
    }

    .remove-btn {
      background: none;
      border: 1.5px solid var(--border);
      color: var(--text-light);
      width: 34px;
      height: 34px;
      border-radius: 10px;
      cursor: pointer;
      font-size: 13px;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all .2s;
      flex-shrink: 0;
    }

    .remove-btn:hover {
      border-color: #C0392B;
      color: #C0392B;
      background: #FDEAE8;
    }

    .cart-empty {
      text-align: center;
      padding: 90px 80px;
      display: none;
    }

    .cart-empty-icon {
      font-size: 60px;
      margin-bottom: 24px;
      opacity: .5;
    }

    .cart-empty h3 {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 26px;
      font-weight: 700;
      color: var(--text-heading);
      margin-bottom: 10px;
    }

    .cart-empty p {
      color: var(--text-muted);
      font-size: 14px;
      margin-bottom: 28px;
      line-height: 1.7;
    }

    /* ORDER SUMMARY */
    .order-summary {
      background: var(--white);
      border-radius: var(--radius-xl);
      border: 1px solid var(--border-light);
      padding: 28px;
      position: sticky;
      top: 84px;
      box-shadow: var(--shadow-md);
    }

    .order-summary h3 {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 22px;
      font-weight: 700;
      margin-bottom: 22px;
      color: var(--text-heading);
    }

    .summary-row {
      display: flex;
      justify-content: space-between;
      font-size: 14px;
      color: var(--text-muted);
      margin-bottom: 12px;
    }

    .summary-divider {
      border: none;
      border-top: 1px solid var(--border-light);
      margin: 18px 0;
    }

    .summary-total {
      display: flex;
      justify-content: space-between;
      align-items: baseline;
      margin-bottom: 22px;
    }

    .summary-total span:first-child {
      font-size: 15px;
      font-weight: 600;
    }

    .summary-total span:last-child {
      font-family: 'Plus Jakarta Sans', sans-serif;
      font-size: 28px;
      color: var(--green);
      font-weight: 800;
    }

    .checkout-btn {
      width: 100%;
      background: var(--green);
      border: none;
      color: white;
      padding: 16px;
      border-radius: 12px;
      font-size: 15px;
      font-weight: 600;
      cursor: pointer;
      font-family: 'Inter', sans-serif;
      transition: all .2s;
      margin-bottom: 12px;
      box-shadow: 0 4px 14px rgba(42, 107, 71, .28);
    }

    .checkout-btn:hover {
      background: var(--green-mid);
      transform: translateY(-1px);
    }

    .continue-btn {
      width: 100%;
      background: transparent;
      border: 1.5px solid var(--border);
      color: var(--text-main);
      padding: 14px;
      border-radius: 12px;
      font-size: 14px;
      font-weight: 500;
      cursor: pointer;
      font-family: 'Inter', sans-serif;
      transition: all .2s;
    }

    .continue-btn:hover {
      border-color: var(--green);
      color: var(--green);
    }

    .eco-note {
      background: var(--green-faint);
      border: 1px solid rgba(42, 107, 71, .15);
      border-radius: 12px;
      padding: 14px 16px;
      margin-top: 18px;
      display: flex;
      gap: 10px;
      align-items: flex-start;
    }

    .eco-note-icon {
      font-size: 16px;
      flex-shrink: 0;
      margin-top: 1px;
    }

    .eco-note p {
      font-size: 12px;
      color: var(--green);
      line-height: 1.6;
    }

    .saved-badge {
      background: var(--amber-pale);
      border: 1px solid rgba(196, 124, 43, .25);
      border-radius: 12px;
      padding: 13px 18px;
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 20px;
    }

    .saved-badge span {
      font-size: 13px;
      color: var(--amber);
    }

    .saved-badge strong {
      font-weight: 700;
    }

    /* ── TOAST ─────────────────────────────────────────────── */
    .toast {
      position: fixed;
      bottom: 28px;
      right: 28px;
      background: var(--text-heading);
      color: white;
      padding: 14px 22px;
      border-radius: 14px;
      font-size: 14px;
      font-family: 'Inter', sans-serif;
      transform: translateY(90px);
      opacity: 0;
      transition: all .3s cubic-bezier(.34, 1.56, .64, 1);
      z-index: 999;
      display: flex;
      align-items: center;
      gap: 10px;
      max-width: 280px;
      box-shadow: 0 8px 28px rgba(0, 0, 0, .2);
    }

    .toast.show {
      transform: translateY(0);
      opacity: 1;
    }

    .toast-icon {
      width: 22px;
      height: 22px;
      background: var(--green);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 12px;
      flex-shrink: 0;
    }

    /* ════════════════════════════════════════════
       RESPONSIVE — TABLET  (≤ 900px)
    ════════════════════════════════════════════ */    /* Ocultar elementos móviles por defecto en escritorio */
    .menu-toggle {
      display: none;
    }

    .mobile-nav {
      display: none;
    }

    @media (max-width: 900px) {

      /* Nav */
      nav {
        padding: 0 40px;
      }

      .nav-links {
        display: none;
      }

      .btn-nav {
        display: none;
      }

      /* Hero */
      .hero {
        grid-template-columns: 1fr;
        padding: 48px 40px 40px;
        gap: 32px;
      }

      .hero h1 {
        font-size: 40px;
      }

      .hero-visual {
        display: none;
      }

      .hero-stats {
        gap: 24px;
      }

      /* Search */
      .search-section {
        padding: 24px 40px;
      }

      .search-wrap {
        flex-wrap: wrap;
        gap: 8px;
      }

      .search-input {
        min-width: 0;
      }

      .filter-select {
        flex: 1 1 calc(50% - 8px);
      }

      .btn-search {
        width: 100%;
      }

      /* Filters */
      .filters-row {
        padding: 14px 40px;
      }

      /* Books section */
      .section {
        padding: 36px 40px;
      }

      .books-grid {
        grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
        gap: 16px;
      }

      /* How it works */
      .how-section {
        padding: 48px 24px;
      }

      .steps-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
      }

      /* Eco banner */
      .eco-banner {
        flex-direction: column;
        padding: 48px 24px;
        gap: 32px;
        text-align: center;
      }

      .eco-text p {
        max-width: 100%;
      }

      .eco-numbers {
        justify-content: center;
      }

      /* Footer */
      footer {
        padding: 40px 40px 24px;
      }

      .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
      }

      .footer-brand {
        grid-column: span 2;
      }

      /* Cart */
      .cart-page {
        padding: 32px 40px;
      }

      .cart-layout {
        grid-template-columns: 1fr;
        gap: 20px;
      }

      .order-summary {
        position: static;
      }
    }

    /* ════════════════════════════════════════════
       RESPONSIVE — MOBILE  (≤ 640px)
    ════════════════════════════════════════════ */
    @media (max-width: 640px) {

      /* Nav — hamburger */
      nav {
        height: 60px;
        padding: 0 24px;
      }

      .btn-sell {
        display: none;
      }

      /* Hamburger button */
      .menu-toggle {
        display: flex;
        flex-direction: column;
        justify-content: center;
        gap: 5px;
        background: none;
        border: none;
        cursor: pointer;
        padding: 4px;
        margin-left: 4px;
      }

      .menu-toggle span {
        display: block;
        width: 22px;
        height: 2px;
        background: var(--text-main);
        border-radius: 2px;
        transition: all .3s;
      }

      /* Mobile nav drawer */
      .mobile-nav {
        display: none;
        flex-direction: column;
        position: fixed;
        inset: 60px 0 0 0;
        background: var(--white);
        z-index: 99;
        padding: 28px 24px;
        gap: 4px;
        border-top: 1px solid var(--border-light);
        animation: slideDown .25s ease;
      }

      .mobile-nav.open {
        display: flex;
      }

      .mobile-nav a {
        font-size: 17px;
        font-weight: 500;
        color: var(--text-main);
        padding: 14px 0;
        border-bottom: 1px solid var(--border-light);
        cursor: pointer;
        text-decoration: none;
        display: block;
      }

      .mobile-nav a:last-child {
        border-bottom: none;
      }

      .mobile-nav .btn-primary {
        margin-top: 16px;
        width: 100%;
        text-align: center;
      }

      @keyframes slideDown {
        from {
          opacity: 0;
          transform: translateY(-8px);
        }

        to {
          opacity: 1;
          transform: translateY(0);
        }
      }

      /* Hero */
      .hero {
        padding: 36px 24px 32px;
      }

      .hero h1 {
        font-size: 32px;
        letter-spacing: -0.5px;
      }

      .hero>div>p {
        font-size: 15px;
      }

      .hero-btns {
        flex-direction: column;
      }

      .hero-btns button {
        width: 100%;
      }

      .hero-stats {
        gap: 18px;
        flex-wrap: wrap;
      }

      .stat-num {
        font-size: 24px;
      }

      /* Search */
      .search-section {
        padding: 18px 24px;
      }

      .search-wrap {
        flex-direction: column;
      }

      .filter-select {
        flex: 1 1 100%;
      }

      /* Filters */
      .filters-row {
        padding: 12px 24px;
      }

      /* Books */
      .section {
        padding: 28px 24px;
      }

      .section-title {
        font-size: 22px;
      }

      .books-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
      }

      .book-cover {
        height: 140px;
        font-size: 34px;
      }

      .book-info {
        padding: 12px 14px;
      }

      .book-title {
        font-size: 13px;
      }

      .book-price {
        font-size: 17px;
      }

      /* How it works */
      .how-section {
        padding: 36px 18px;
      }

      .steps-grid {
        grid-template-columns: 1fr;
      }

      .step-card {
        padding: 24px 20px;
        text-align: left;
        display: flex;
        flex-direction: column;
        align-items: flex-start;
      }

      .step-icon {
        margin: 0 0 14px;
      }

      /* Eco banner */
      .eco-banner {
        padding: 36px 18px;
      }

      .eco-text h2 {
        font-size: 24px;
      }

      .eco-numbers {
        gap: 24px;
        flex-wrap: wrap;
        justify-content: center;
      }

      .eco-divider {
        display: none;
      }

      .eco-num .num {
        font-size: 30px;
      }

      /* Footer */
      footer {
        padding: 32px 24px 20px;
      }

      .footer-grid {
        grid-template-columns: 1fr;
        gap: 24px;
      }

      .footer-brand {
        grid-column: span 1;
      }

      .footer-bottom {
        flex-direction: column;
        gap: 6px;
        text-align: center;
      }

      /* Cart */
      .cart-page {
        padding: 24px 24px;
      }

      .cart-page h2 {
        font-size: 26px;
      }

      .cart-item {
        flex-wrap: wrap;
        gap: 12px;
      }

      .cart-item-cover {
        width: 52px;
        height: 64px;
        font-size: 22px;
      }

      .cart-item-price {
        font-size: 18px;
      }

      /* Toast */
      .toast {
        left: 24px;
        right: 24px;
        max-width: 100%;
        bottom: 18px;
      }
    }

    /* ════════════════════════════════════════════
       RESPONSIVE — SMALL MOBILE (≤ 400px)
    ════════════════════════════════════════════ */
    @media (max-width: 400px) {
      .hero h1 {
        font-size: 28px;
      }

      .books-grid {
        grid-template-columns: 1fr;
      }

      .eco-numbers {
        flex-direction: column;
        align-items: center;
        gap: 16px;
      }
    }