/* =========================================================
   RUBÉN A. TOBAR — sitio de autor
   Sistema de diseño: "Planta y Manuscrito"
   Dualidad entre la línea de producción (fábrica, precisión,
   la fórmula E×C×T=R) y la mesa de escritura (papel kraft,
   voz literaria). Fraunces para el pulso literario, la
   familia IBM Plex para la precisión técnica y las cifras.
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Fraunces:ital,opsz,wght@0,9..144,300;0,9..144,400;0,9..144,500;0,9..144,600;0,9..144,700;1,9..144,400;1,9..144,500&family=IBM+Plex+Sans:wght@300;400;500;600;700&family=IBM+Plex+Mono:wght@400;500;600&display=swap');

:root {
  /* --- color: 6 valores nombrados --- */
  --graphite:      #12181F; /* fondo "planta" — noche de fábrica, tinta de plano técnico */
  --graphite-2:     #1B232D; /* panel ligeramente más claro sobre graphite */
  --kraft:          #D9C4A0; /* papel kraft — fondo "manuscrito" */
  --kraft-light:    #EFE3C8; /* kraft claro para tarjetas / superficies elevadas */
  --ember:          #C1622D; /* cobre / ascua — acento cálido, fe y constancia */
  --steel:          #5C86A6; /* azul plano técnico — acento frío, precisión */
  --ink:            #1B1F26; /* texto oscuro sobre kraft */
  --paper:          #F3EBDA; /* texto claro sobre graphite */

  --line-on-dark:  rgba(243,235,218,0.16);
  --line-on-light: rgba(27,31,38,0.18);

  --font-display: 'Fraunces', Georgia, serif;
  --font-body: 'IBM Plex Sans', -apple-system, sans-serif;
  --font-mono: 'IBM Plex Mono', 'Courier New', monospace;

  --wrap: 1120px;
  --edge: clamp(20px, 5vw, 64px);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

body {
  margin: 0;
  background: var(--kraft);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a { color: inherit; }

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.08;
  margin: 0 0 0.5em;
  letter-spacing: -0.01em;
}

p { margin: 0 0 1em; }

.container {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 var(--edge);
}

/* focus visibility */
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--ember);
  outline-offset: 3px;
}

/* =========================================================
   NAV
   ========================================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: var(--graphite);
  color: var(--paper);
  border-bottom: 1px solid var(--line-on-dark);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px var(--edge);
  max-width: var(--wrap);
  margin: 0 auto;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  text-decoration: none;
  color: var(--paper);
}

.brand-name {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 500;
  font-size: 1.25rem;
  white-space: nowrap;
}

.brand-formula {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  color: var(--ember);
  border: 1px solid var(--line-on-dark);
  padding: 3px 7px;
  border-radius: 3px;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  gap: 28px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  text-decoration: none;
  font-size: 0.92rem;
  color: var(--paper);
  opacity: 0.82;
  position: relative;
  padding: 4px 0;
}

.nav-links a:hover { opacity: 1; }

.nav-links a[aria-current="page"] {
  opacity: 1;
  border-bottom: 1px solid var(--ember);
}

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--line-on-dark);
  border-radius: 4px;
  color: var(--paper);
  width: 40px;
  height: 36px;
  font-size: 1.1rem;
  cursor: pointer;
}

@media (max-width: 760px) {
  .nav-toggle { display: block; }
  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--graphite);
    flex-direction: column;
    gap: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.28s ease;
    border-bottom: 1px solid var(--line-on-dark);
  }
  .nav-links.open { max-height: 320px; }
  .nav-links li { border-top: 1px solid var(--line-on-dark); }
  .nav-links a { display: block; padding: 14px var(--edge); }
}

/* =========================================================
   HERO — esquema de la ecuación E × C × T = R
   ========================================================= */
.hero {
  background: var(--graphite);
  color: var(--paper);
  padding: clamp(48px, 9vw, 108px) var(--edge) clamp(56px, 10vw, 120px);
  position: relative;
  overflow: hidden;
}

.hero::before {
  /* líneas de plano técnico, muy sutiles */
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--line-on-dark) 1px, transparent 1px),
    linear-gradient(90deg, var(--line-on-dark) 1px, transparent 1px);
  background-size: 42px 42px;
  opacity: 0.35;
  pointer-events: none;
}

.hero-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  position: relative;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--steel);
  margin-bottom: 18px;
  display: block;
}

.hero h1 {
  font-size: clamp(2.3rem, 5.5vw, 3.8rem);
  max-width: 14ch;
  color: var(--paper);
}

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

.hero-lede {
  font-size: 1.1rem;
  max-width: 52ch;
  color: var(--paper);
  opacity: 0.86;
  margin-top: 18px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  margin-top: 32px;
  flex-wrap: wrap;
}

/* --- el esquema interactivo --- */
.equation-schematic {
  margin-top: clamp(48px, 8vw, 84px);
  display: flex;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px 4px;
  font-family: var(--font-mono);
}

.eq-term {
  background: transparent;
  border: 1px solid var(--line-on-dark);
  border-radius: 6px;
  padding: 16px 18px;
  min-width: 128px;
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
  text-align: left;
  color: inherit;
  font-family: inherit;
}

.eq-term:hover, .eq-term:focus-visible, .eq-term.is-active {
  border-color: var(--ember);
  background: rgba(193,98,45,0.08);
}

.eq-letter {
  display: block;
  font-size: 2rem;
  font-weight: 600;
  color: var(--ember);
  line-height: 1;
}

.eq-word {
  display: block;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--paper);
  opacity: 0.7;
  margin-top: 8px;
}

.eq-def {
  display: block;
  max-width: 34ch;
  font-family: var(--font-body);
  font-size: 0.86rem;
  color: var(--paper);
  opacity: 0;
  max-height: 0;
  overflow: hidden;
  transition: opacity 0.2s ease, max-height 0.2s ease, margin 0.2s ease;
}

.eq-term.is-active .eq-def,
.eq-term:focus-visible .eq-def {
  opacity: 0.86;
  max-height: 120px;
  margin-top: 10px;
}

.eq-op, .eq-eq {
  align-self: center;
  font-size: 1.6rem;
  color: var(--steel);
  padding: 0 2px;
}

.eq-result {
  border-color: var(--ember) !important;
  background: rgba(193,98,45,0.1);
}
.eq-result .eq-letter { color: var(--paper); }
.eq-result .eq-word { color: var(--ember); opacity: 1; }

@media (max-width: 640px) {
  .equation-schematic { gap: 10px; }
  .eq-op, .eq-eq { display: none; }
  .eq-term { width: 100%; }
}

/* =========================================================
   DIVISIONES 2 COLUMNAS RESPONSIVAS (portada + texto)
   ========================================================= */
.split-hero {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 56px;
  align-items: center;
}
.split-feature {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 48px;
  align-items: center;
}
@media (max-width: 700px) {
  .split-hero, .split-feature {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .split-hero .book-cover, .split-feature .book-cover {
    max-width: 240px;
    margin: 0 auto;
  }
}

/* =========================================================
   BOTONES
   ========================================================= */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 13px 24px;
  border-radius: 4px;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.btn:hover { transform: translateY(-1px); }

.btn-primary {
  background: var(--ember);
  color: var(--paper);
}
.btn-primary:hover { background: #A6531F; }

.btn-ghost {
  background: transparent;
  color: var(--paper);
  border-color: var(--line-on-dark);
}
.btn-ghost:hover { border-color: var(--paper); }

.btn-ghost-dark {
  background: transparent;
  color: var(--ink);
  border-color: var(--line-on-light);
}
.btn-ghost-dark:hover { border-color: var(--ink); }

/* =========================================================
   SECCIONES / RITMO CLARO-OSCURO
   ========================================================= */
.section {
  padding: clamp(56px, 9vw, 100px) var(--edge);
}

.section-kraft { background: var(--kraft); color: var(--ink); }
.section-dark  { background: var(--graphite); color: var(--paper); }
.section-kraft-light { background: var(--kraft-light); color: var(--ink); }

.section-head {
  max-width: var(--wrap);
  margin: 0 auto 40px;
}

.section-inner {
  max-width: var(--wrap);
  margin: 0 auto;
}

.kicker {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  display: inline-block;
  padding-bottom: 10px;
  margin-bottom: 14px;
  border-bottom: 1px solid var(--ember);
  color: var(--ember);
}

.section-dark .kicker { color: var(--steel); border-color: var(--steel); }

.section-title {
  font-size: clamp(1.7rem, 3.4vw, 2.3rem);
  max-width: 20ch;
}

.section-lede {
  max-width: 58ch;
  font-size: 1.05rem;
  opacity: 0.85;
}

/* =========================================================
   TARJETAS DE LIBRO — evocan una caja de cartón corrugado
   ========================================================= */
.book-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 28px;
}

.book-card {
  background: var(--kraft-light);
  border: 1.5px dashed rgba(27,31,38,0.35);
  border-radius: 2px;
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  text-decoration: none;
  color: var(--ink);
  position: relative;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.book-card:hover {
  border-color: var(--ember);
  transform: translateY(-3px);
}

.book-card::before {
  /* esquina de "solapa de caja" */
  content: "";
  position: absolute;
  top: -1.5px; left: -1.5px;
  width: 22px; height: 22px;
  border-top: 1.5px dashed rgba(27,31,38,0.35);
  border-left: 1.5px dashed rgba(27,31,38,0.35);
}

.book-cover {
  aspect-ratio: 5 / 7;
  width: 100%;
  border-radius: 2px;
  background: linear-gradient(155deg, var(--graphite), var(--graphite-2));
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  text-align: center;
  overflow: hidden;
}

.book-cover:has(img) {
  padding: 0;
}

.book-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 2px;
  display: block;
}

/* Insignia para libros con edición en inglés */
.book-lang-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--steel);
  border: 1px solid rgba(27,31,38,0.25);
  border-radius: 3px;
  padding: 3px 8px;
  margin-top: 10px;
}


.book-cover-formula {
  font-family: var(--font-mono);
  color: var(--ember);
  font-size: 1.1rem;
  letter-spacing: 0.04em;
}
.book-cover-title {
  font-family: var(--font-display);
  color: var(--paper);
  font-size: 1.15rem;
  font-style: italic;
  margin-top: 14px;
}

.book-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ember);
}

.book-title { font-size: 1.35rem; margin-bottom: 0; }

.book-excerpt {
  font-size: 0.94rem;
  opacity: 0.82;
  margin-bottom: 0;
}

.book-meta {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  opacity: 0.7;
  margin-top: auto;
}

/* =========================================================
   BLOG
   ========================================================= */
.post-list {
  display: flex;
  flex-direction: column;
}

.post-row {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 24px;
  padding: 26px 0;
  border-top: 1px solid var(--line-on-light);
  text-decoration: none;
  color: var(--ink);
}

.section-dark .post-row { border-color: var(--line-on-dark); color: var(--paper); }

.post-list a.post-row:last-child { border-bottom: 1px solid var(--line-on-light); }

.post-date {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  opacity: 0.65;
  padding-top: 4px;
}

.post-title {
  font-family: var(--font-display);
  font-size: 1.35rem;
  margin-bottom: 8px;
  transition: color 0.15s ease;
}

.post-row:hover .post-title { color: var(--ember); }

.post-excerpt { opacity: 0.82; margin-bottom: 0; font-size: 0.96rem; }

.post-category {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ember);
  margin-bottom: 6px;
  display: inline-block;
}

@media (max-width: 560px) {
  .post-row { grid-template-columns: 1fr; gap: 6px; }
}

/* artículo individual */
.article {
  max-width: 70ch;
  margin: 0 auto;
}

.article-header { margin-bottom: 36px; }

.article-body p { font-size: 1.05rem; line-height: 1.75; }
.article-body h2 {
  font-size: 1.5rem;
  margin-top: 1.6em;
}
.article-body blockquote {
  margin: 2em 0;
  padding: 4px 0 4px 22px;
  border-left: 3px solid var(--ember);
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.2rem;
}

/* =========================================================
   BIO / SOBRE MÍ
   ========================================================= */
.bio-grid {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 56px;
  align-items: start;
}

@media (max-width: 780px) {
  .bio-grid { grid-template-columns: 1fr; }
}

.bio-portrait {
  aspect-ratio: 4 / 5;
  background: var(--graphite);
  border-radius: 2px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  text-align: center;
  padding: 24px;
  opacity: 0.9;
  overflow: hidden;
}

.bio-portrait:has(img) {
  padding: 0;
  opacity: 1;
}

.bio-portrait img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 2px;
  display: block;
}

.fact-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 22px;
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--line-on-light);
}

.section-dark .fact-strip { border-color: var(--line-on-dark); }

.fact-num {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  color: var(--ember);
  display: block;
}

.fact-label {
  font-size: 0.85rem;
  opacity: 0.75;
  margin-top: 4px;
}

/* =========================================================
   CONTACTO
   ========================================================= */
.form-grid {
  display: grid;
  gap: 18px;
  max-width: 560px;
}

label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 8px;
  opacity: 0.75;
}

input, textarea {
  width: 100%;
  font-family: var(--font-body);
  font-size: 1rem;
  padding: 13px 14px;
  border: 1px solid var(--line-on-light);
  border-radius: 4px;
  background: var(--kraft-light);
  color: var(--ink);
}

.section-dark input, .section-dark textarea {
  background: var(--graphite-2);
  border-color: var(--line-on-dark);
  color: var(--paper);
}

textarea { resize: vertical; min-height: 140px; }

.contact-alt {
  display: flex;
  gap: 32px;
  flex-wrap: wrap;
  margin-top: 44px;
  padding-top: 28px;
  border-top: 1px solid var(--line-on-light);
}

.contact-alt-item .kicker { margin-bottom: 8px; }

/* =========================================================
   FOOTER
   ========================================================= */
.site-footer {
  background: var(--graphite);
  color: var(--paper);
  padding: 44px var(--edge) 30px;
}

.footer-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 24px;
  align-items: flex-end;
}

.footer-formula {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--ember);
  opacity: 0.9;
}

.footer-note {
  font-size: 0.82rem;
  opacity: 0.55;
  margin-top: 6px;
}

.footer-links {
  display: flex;
  gap: 20px;
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 0.86rem;
}

.footer-links a { text-decoration: none; opacity: 0.75; }
.footer-links a:hover { opacity: 1; }

/* =========================================================
   REVELADO AL HACER SCROLL (sutil)
   ========================================================= */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* =========================================================
   UTILIDADES
   ========================================================= */
.mt-0 { margin-top: 0; }
.text-center { text-align: center; }
.divider-mono {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--ember);
  text-align: center;
  margin: 0 auto 40px;
}