/* ============================================================
   EduBlog — Tema "Dark Realm"
   Introducción a la Informática (UNA, 2026-2)
   Hoja de estilos global. Modo oscuro obligatorio.
   ============================================================ */

/* ---------- 1. Variables ---------- */
:root {
  --bg:          #0d0d12;
  --surface:     #12121a;
  --surface-2:   #1a1a2e;
  --border:      #2a2a3d;
  --text:        #e0e0e0;
  --heading:     #f0f0f5;
  --primary:     #00e5ff;
  --secondary:   #7c4dff;
  --warning:     #ff7043;
  --quote-bg:    #16161f;
  --quote-text:  #cfd8dc;
  --muted:       #8a8aa3;

  --radius:      12px;
  --radius-sm:   8px;
  --shadow:      0 6px 24px rgba(0, 0, 0, 0.45);
  --glow-cyan:   0 0 0 1px rgba(0, 229, 255, 0.55), 0 8px 30px rgba(0, 229, 255, 0.18);
  --glow-violet: 0 0 0 1px rgba(124, 77, 255, 0.55), 0 8px 30px rgba(124, 77, 255, 0.22);

  --font-head: 'Montserrat', 'Poppins', 'Segoe UI', sans-serif;
  --font-body: 'Inter', 'Segoe UI', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Consolas', monospace;

  --maxw: 1120px;
  --header-h: 68px;
}

/* ---------- 2. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--primary); text-decoration: none; transition: color .2s ease; }
a:hover { color: var(--secondary); }

h1, h2, h3, h4 {
  font-family: var(--font-head);
  color: var(--heading);
  line-height: 1.25;
  margin: 1.6em 0 .6em;
  font-weight: 700;
}
h1 { font-size: clamp(1.9rem, 4vw, 2.8rem); }
h2 { font-size: clamp(1.4rem, 3vw, 1.9rem); }
h3 { font-size: clamp(1.15rem, 2.4vw, 1.4rem); }
h2, h3 { scroll-margin-top: calc(var(--header-h) + 20px); }

p { margin: 0 0 1em; }

ul, ol { padding-left: 1.4em; }
li { margin-bottom: .4em; }

strong { color: var(--heading); }

hr {
  border: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border), transparent);
  margin: 2.5rem 0;
}

/* ---------- 3. Layout ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}

main { display: block; padding-bottom: 3rem; }

/* ---------- 4. Header / Navegación ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 13, 18, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
}

.brand {
  display: flex;
  align-items: center;
  gap: .6rem;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--heading);
  letter-spacing: .5px;
}
.brand:hover { color: var(--primary); }
.brand .brand-dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 0 12px var(--primary);
}

.main-nav ul {
  display: flex;
  align-items: center;
  gap: .25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.main-nav a {
  display: block;
  padding: .5rem .8rem;
  border-radius: var(--radius-sm);
  font-size: .92rem;
  color: var(--text);
  font-weight: 500;
  white-space: nowrap;
}
.main-nav a:hover { color: var(--primary); background: rgba(0, 229, 255, 0.08); }
.main-nav a.active {
  color: var(--bg);
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  font-weight: 700;
}

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--heading);
  font-size: 1.4rem;
  line-height: 1;
  padding: .35rem .6rem;
  cursor: pointer;
}

/* ---------- 5. Hero banner ---------- */
.hero-banner {
  position: relative;
  width: 100%;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}
.hero-banner img {
  width: 100%;
  height: clamp(180px, 32vw, 360px);
  object-fit: cover;
}
.hero-banner::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(13,13,18,0.35) 0%, rgba(13,13,18,0.05) 40%, rgba(13,13,18,0.85) 100%);
  pointer-events: none;
}

.page-head { padding-top: 2rem; }
.page-head h1 { margin-top: 0; }

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--primary);
  border: 1px solid rgba(0, 229, 255, 0.35);
  border-radius: 999px;
  padding: .25rem .8rem;
  margin-bottom: .8rem;
}

/* ---------- 6. Bloques de contenido ---------- */
.lead { font-size: 1.12rem; color: var(--quote-text); }

blockquote {
  margin: 1.8rem 0;
  padding: 1rem 1.4rem;
  background: var(--quote-bg);
  border-left: 4px solid var(--primary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--quote-text);
  font-style: italic;
}
blockquote p:last-child { margin-bottom: 0; }

.callout {
  margin: 1.8rem 0;
  padding: 1rem 1.3rem;
  background: rgba(255, 112, 67, 0.08);
  border: 1px solid rgba(255, 112, 67, 0.4);
  border-left: 4px solid var(--warning);
  border-radius: var(--radius-sm);
  color: var(--text);
}
.callout strong { color: var(--warning); }

figure { margin: 2rem 0; }
figure img {
  width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}
figure figcaption {
  margin-top: .6rem;
  font-size: .85rem;
  color: var(--muted);
  text-align: center;
  font-style: italic;
}

/* ---------- 7. Tarjetas / Grid ---------- */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.4rem;
  margin: 2rem 0;
}

.card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid rgba(124, 77, 255, 0.35);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.card:hover {
  transform: translateY(-5px);
  border-color: rgba(0, 229, 255, 0.6);
  box-shadow: var(--glow-cyan);
}
.card .card-media {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
}
.card .card-media img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform .4s ease;
}
.card:hover .card-media img { transform: scale(1.05); }
.card .card-body {
  padding: 1.1rem 1.2rem 1.3rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}
.card h3 {
  margin: 0 0 .5rem;
  font-size: 1.1rem;
  color: var(--heading);
}
.card p {
  font-size: .93rem;
  color: var(--muted);
  flex: 1;
}
.card .card-link {
  margin-top: .8rem;
  font-weight: 700;
  font-size: .9rem;
  color: var(--primary);
  display: inline-flex;
  align-items: center;
  gap: .4rem;
}
.card .card-link::after { content: "→"; transition: transform .2s ease; }
.card:hover .card-link::after { transform: translateX(4px); }

/* Tabla de datos (Datos del trabajo / equivalencias) */
.data-table, table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.6rem 0;
  font-size: .93rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
table thead th {
  background: linear-gradient(135deg, rgba(124,77,255,0.35), rgba(124,77,255,0.12));
  color: var(--heading);
  text-align: left;
  font-family: var(--font-head);
  font-weight: 700;
  padding: .75rem .9rem;
  border-bottom: 1px solid var(--border);
}
table td {
  padding: .7rem .9rem;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
table tbody tr:nth-child(even) { background: var(--surface-2); }
table tbody tr:last-child td { border-bottom: 0; }

.table-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.table-scroll table { min-width: 560px; margin: 1.6rem 0; }

.mono { font-family: var(--font-mono); }

/* ---------- 8. Video ---------- */
.video-card {
  margin: 2rem 0;
  background: var(--surface);
  border: 1px solid rgba(0, 229, 255, 0.35);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--glow-cyan);
}
.video-frame {
  position: relative;
  aspect-ratio: 16 / 9;
  background: #000;
}
.video-frame iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}
.video-meta { padding: 1rem 1.2rem; }
.video-meta .video-title { font-weight: 700; color: var(--heading); }
.video-meta .video-source { font-size: .85rem; color: var(--muted); }

/* ---------- 9. Navegación inferior (Anterior · Inicio · Siguiente) ---------- */
.page-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 1rem;
  align-items: stretch;
  margin: 3rem 0 1rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}
.page-nav a {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: .9rem 1.1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  transition: border-color .2s ease, box-shadow .2s ease, transform .2s ease;
}
.page-nav a:hover {
  border-color: rgba(0, 229, 255, 0.6);
  box-shadow: var(--glow-cyan);
  transform: translateY(-3px);
}
.page-nav .label {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: .25rem;
}
.page-nav .title { font-weight: 600; color: var(--heading); font-size: .95rem; }
.page-nav .nav-home { text-align: center; }
.page-nav .nav-next { text-align: right; align-items: flex-end; }
.page-nav .nav-prev { text-align: left; }
.page-nav .is-disabled { visibility: hidden; }

/* ---------- 10. Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  padding: 2rem 0;
  margin-top: 2rem;
}
.site-footer .container {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
}
.site-footer p { margin: 0; font-size: .85rem; color: var(--muted); }
.site-footer .footer-links { display: flex; gap: 1rem; flex-wrap: wrap; }
.site-footer .footer-links a { font-size: .85rem; }

/* ---------- 11. Portada (home) ---------- */
.home-hero { text-align: center; padding: 2.4rem 0 1rem; }
.home-hero h1 { margin-bottom: .3rem; }
.home-hero .subtitle {
  font-family: var(--font-head);
  font-size: clamp(1.05rem, 2.4vw, 1.5rem);
  color: var(--primary);
  font-weight: 600;
  letter-spacing: 1px;
  margin-bottom: 1.4rem;
}

.section-title {
  display: flex;
  align-items: center;
  gap: .8rem;
  margin-top: 3rem;
}
.section-title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--border), transparent);
}

/* ---------- 12. Utilidades ---------- */
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* ---------- 13. Responsive ---------- */
@media (max-width: 900px) {
  .cards-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  :root { --header-h: 60px; }

  .nav-toggle { display: inline-block; }

  .main-nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    max-height: 0;
    overflow: hidden;
    transition: max-height .3s ease;
  }
  .main-nav.open { max-height: 520px; overflow-y: auto; }
  .main-nav ul {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: .5rem;
  }
  .main-nav a { padding: .8rem 1rem; font-size: 1rem; }

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

  .page-nav { grid-template-columns: 1fr; }
  .page-nav .nav-home, .page-nav .nav-next { text-align: left; align-items: flex-start; }
  .page-nav .is-disabled { display: none; }

  body { font-size: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; scroll-behavior: auto !important; }
}