/* ============================================================
   BIBIA — bibia/styles.css
   Identidad de BIBIA: modo claro, acento azul, estilo educativo.
   Basada en la estética de bibia-biblioteca.netlify.app.
   ============================================================ */

:root {
  --b-bg: #fafafa;
  --b-bg-alt: #ffffff;
  --b-bg-tertiary: #f3f4f6;
  --b-text: #1a1a2e;
  --b-text-secondary: #4a5568;
  --b-text-muted: #718096;
  --b-border: #e2e8f0;
  --b-accent: #2563eb;
  --b-accent-hover: #1d4ed8;
  --b-accent-light: #dbeafe;
  --b-radius: 14px;
  --b-font: 'Inter', -apple-system, sans-serif;
  --b-mono: 'JetBrains Mono', ui-monospace, monospace;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background: var(--b-bg);
  color: var(--b-text);
  font-family: var(--b-font);
  font-size: 16px;
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--b-accent);
}

/* ── Header ── */
.b-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--b-border);
}

.b-nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.b-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--b-text);
}

.b-logo-icon {
  font-size: 22px;
}

.b-logo-text {
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
}

.b-nav-links {
  display: flex;
  gap: 28px;
}

.b-nav-links a {
  font-size: 15px;
  font-weight: 500;
  color: var(--b-text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

.b-nav-links a:hover {
  color: var(--b-accent);
}

/* ── Buttons ── */
.b-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: 10px;
  font-family: var(--b-font);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s ease;
}

.b-btn-primary {
  background: var(--b-accent);
  color: #ffffff;
}

.b-btn-primary:hover {
  background: var(--b-accent-hover);
}

.b-btn-outline {
  background: transparent;
  color: var(--b-accent);
  border-color: var(--b-border);
}

.b-btn-outline:hover {
  border-color: var(--b-accent);
}

.b-btn-dark {
  background: #111827;
  color: #ffffff;
}

.b-btn-dark:hover {
  background: #1f2937;
}

.b-btn-lg {
  padding: 14px 30px;
  font-size: 16px;
}

.b-btn-xl {
  padding: 18px 40px;
  font-size: 17px;
  border-radius: 12px;
}

/* ── Hero ── */
.b-hero {
  background: var(--b-bg);
  background-image: radial-gradient(circle at 50% 0%, rgba(37, 99, 235, 0.08), transparent 60%);
  padding: 96px 24px 80px;
  text-align: center;
}

.b-hero-inner {
  max-width: 700px;
  margin: 0 auto;
}

.b-badge {
  display: inline-block;
  font-family: var(--b-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--b-accent);
  background: var(--b-accent-light);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: 100px;
  padding: 6px 14px;
  margin-bottom: 24px;
}

.b-title {
  font-size: clamp(4rem, 12vw, 7rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
  background: linear-gradient(135deg, var(--b-accent), #8b5cf6);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 12px;
}

.b-subtitle {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--b-text);
  margin-bottom: 12px;
}

.b-subtitle strong {
  color: var(--b-accent);
}

.b-desc {
  color: var(--b-text-secondary);
  font-size: 1.05rem;
  margin-bottom: 36px;
}

.b-hero-actions {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ── Sections ── */
.b-section {
  padding: 88px 24px;
}

.b-bg-alt {
  background: var(--b-bg-alt);
  border-top: 1px solid var(--b-border);
  border-bottom: 1px solid var(--b-border);
}

.b-container {
  max-width: 1200px;
  margin: 0 auto;
}

.b-narrow {
  max-width: 760px;
  text-align: center;
}

.b-eyebrow {
  display: block;
  font-family: var(--b-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--b-accent);
  margin-bottom: 14px;
}

.b-h2 {
  font-size: clamp(1.7rem, 4vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: 24px;
}

.b-accent {
  color: var(--b-accent);
}

.b-lead {
  color: var(--b-text-secondary);
  font-size: 1.06rem;
  margin-bottom: 16px;
}

.b-lead strong {
  color: var(--b-text);
}

/* ── Features ── */
.b-features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 40px;
}

.b-feature {
  background: var(--b-bg-alt);
  border: 1px solid var(--b-border);
  border-radius: var(--b-radius);
  padding: 28px 24px;
  transition: all 0.25s ease;
}

.b-feature:hover {
  transform: translateY(-3px);
  border-color: var(--b-accent);
  box-shadow: 0 20px 50px rgba(37, 99, 235, 0.08);
}

.b-feature-icon {
  font-size: 28px;
  margin-bottom: 14px;
}

.b-feature h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.b-feature p {
  color: var(--b-text-secondary);
  font-size: 14px;
}

/* ── Categorías ── */
.b-cats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 40px;
}

.b-cat {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  background: var(--b-bg-alt);
  border: 1px solid var(--b-border);
  border-radius: var(--b-radius);
  padding: 22px 20px;
  text-decoration: none;
  color: inherit;
  transition: all 0.25s ease;
}

.b-cat:hover {
  transform: translateY(-3px);
  border-color: var(--cat, var(--b-accent));
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.06);
}

.b-cat-icon {
  font-size: 24px;
  flex-shrink: 0;
}

.b-cat h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.b-cat p {
  color: var(--b-text-muted);
  font-size: 13px;
  line-height: 1.5;
}

.b-cat-soon {
  cursor: default;
}

.b-cat-soon:hover {
  transform: none;
  border-color: var(--b-border);
}

.b-tag-soon {
  display: inline-block;
  font-family: var(--b-mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: var(--b-bg-tertiary);
  color: var(--b-text-muted);
  border: 1px solid var(--b-border);
  border-radius: 100px;
  padding: 2px 8px;
  vertical-align: middle;
  margin-left: 6px;
}

/* ── CTA ── */
.b-cta {
  text-align: center;
  padding: 88px 24px;
  background: var(--b-bg-alt);
  border-top: 1px solid var(--b-border);
}

.b-cta-badge {
  display: inline-block;
  font-family: var(--b-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--b-accent);
  margin-bottom: 20px;
}

.b-cta h2 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 12px;
}

.b-cta p {
  color: var(--b-text-secondary);
  margin-bottom: 32px;
}

.b-cta-note {
  margin-top: 24px;
  font-size: 13px;
  color: var(--b-text-muted);
}

/* ── Footer ── */
.b-footer {
  background: var(--b-text);
  color: #cbd5e1;
  padding: 48px 0 32px;
}

.b-footer .b-logo-text {
  color: #ffffff;
}

.b-footer-top {
  display: flex;
  justify-content: space-between;
  gap: 40px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}

.b-footer-brand {
  max-width: 320px;
}

.b-footer-brand p {
  margin-top: 12px;
  font-size: 13px;
  color: #94a3b8;
}

.b-footer-cols {
  display: flex;
  gap: 56px;
}

.b-footer-cols h4 {
  font-family: var(--b-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #94a3b8;
  margin-bottom: 14px;
}

.b-footer-cols ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.b-footer-cols a {
  color: #cbd5e1;
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s ease;
}

.b-footer-cols a:hover {
  color: #ffffff;
}

.b-footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 24px;
  font-size: 13px;
  color: #94a3b8;
}

/* ── Responsive ── */
@media (max-width: 1024px) {
  .b-cats {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .b-nav-links {
    display: none;
  }

  .b-features {
    grid-template-columns: 1fr;
  }

  .b-cats {
    grid-template-columns: 1fr;
  }

  .b-section {
    padding: 64px 20px;
  }

  .b-hero {
    padding: 72px 20px 64px;
  }

  .b-footer-cols {
    gap: 32px;
    flex-wrap: wrap;
  }
}