/* Brintune — hoja de muestras / specimen sheet
   Paleta papel ocre, tinta negra, acento azul y ocre oscuro */

:root {
  --paper: #f4eee1;
  --paper-alt: #e8dfcc;
  --dark: #141414;
  --ink: #1a1814;
  --muted: #736c5b;
  --accent: #2b4a8c;
  --ochre: #8a6a1e;
  --line: rgba(115, 108, 91, 0.45);
  --mono: ui-monospace, Consolas, "Liberation Mono", monospace;
  --sans: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --pad: clamp(20px, 4vw, 44px);
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.75;
  overflow-wrap: break-word;
}

/* ---------- Podloga / hoja ---------- */

.sheet {
  max-width: 1180px;
  margin: clamp(20px, 4vw, 48px) auto 0;
  border: 1px solid var(--accent);
  background: var(--paper);
}

.band {
  padding: 44px var(--pad);
}

.band--alt { background: var(--paper-alt); }

.band--dark {
  background: var(--dark);
  color: var(--paper);
}

.band--dark a { color: #b9c9ee; }
.band--dark .meta,
.band--dark .caption { color: #b3aa96; }
.band--dark .spec {
  border-color: rgba(244, 238, 225, 0.28);
  color: var(--paper);
}
.band--dark .spec dt { color: #b3aa96; }

/* ---------- Rejilla de 12 columnas ---------- */

.grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  column-gap: 28px;
  row-gap: 32px;
  align-items: start;
}

.c1-8 { grid-column: 1 / 9; }
.c1-7 { grid-column: 1 / 8; }
.c1-6 { grid-column: 1 / 7; }
.c1-5 { grid-column: 1 / 6; }
.c9-12 { grid-column: 9 / -1; }
.c8-12 { grid-column: 8 / -1; }
.c7-12 { grid-column: 7 / -1; }
.c6-12 { grid-column: 6 / -1; }
.full { grid-column: 1 / -1; }

/* ---------- Tipografía ---------- */

h1, h2, h3, .meta, nav, .spec, .num, .caption, .brand {
  font-family: var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.09em;
}

h1 {
  margin: 0;
  font-size: clamp(28px, 4.4vw, 46px);
  line-height: 1.22;
  font-weight: 600;
  letter-spacing: 0.02em;
}

h2 {
  margin: 0 0 18px;
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.4;
  font-weight: 600;
}

h3 {
  margin: 30px 0 10px;
  font-size: 14px;
  font-weight: 600;
  color: var(--ochre);
  letter-spacing: 0.14em;
}

.band--dark h3 { color: #c9a84f; }

.num {
  display: block;
  margin-bottom: 14px;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--ochre);
}

.meta {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

p { margin: 0 0 18px; }
p:last-child { margin-bottom: 0; }

.lead { font-size: 19px; }

.muted { color: var(--muted); }

a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.band--dark :focus-visible { outline-color: #b9c9ee; }

/* ---------- Tablillas laterales ---------- */

.spec {
  border: 1px solid var(--line);
  padding: 16px 18px;
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 1.65;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.spec + .spec { margin-top: 20px; }

.spec p { text-transform: none; letter-spacing: 0.02em; }

.spec h2,
.spec .spec-title {
  display: block;
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--ochre);
}

.spec dl {
  margin: 0;
  display: grid;
  grid-template-columns: auto;
  row-gap: 10px;
}

.spec dt {
  margin: 0;
  color: var(--muted);
  font-size: 11px;
  letter-spacing: 0.16em;
}

.spec dd { margin: 0; }

.spec a { text-transform: none; letter-spacing: 0.02em; }

/* ---------- Listas ---------- */

ul.checks, ul.plain {
  margin: 0 0 18px;
  padding: 0;
  list-style: none;
}

ul.checks li, ul.plain li {
  position: relative;
  padding-left: 26px;
  margin-bottom: 10px;
}

ul.checks li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 12px;
  height: 1px;
  background: var(--accent);
}

ul.plain li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 10px;
  width: 5px;
  height: 5px;
  background: var(--ochre);
}

.band--dark ul.checks li::before { background: #b9c9ee; }

ol.steps {
  margin: 0 0 18px;
  padding-left: 22px;
}

ol.steps li { margin-bottom: 10px; }

/* ---------- Separadores ---------- */

.rule {
  position: relative;
  height: 1px;
  background: var(--line);
  margin: 0 var(--pad);
}

.rule::before,
.rule::after {
  content: "";
  position: absolute;
  top: -6px;
  width: 1px;
  height: 13px;
  background: var(--ochre);
}

.rule::before { left: 0; }
.rule::after { right: 0; }

/* ---------- Cabecera y navegación ---------- */

.masthead {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 28px;
  align-items: baseline;
  justify-content: space-between;
  padding: 22px var(--pad);
  border-bottom: 1px solid var(--line);
}

.brand {
  font-size: 15px;
  letter-spacing: 0.28em;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
}

.masthead nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 11.5px;
  letter-spacing: 0.16em;
}

.masthead nav a {
  color: var(--muted);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
}

.masthead nav a:hover,
.masthead nav a[aria-current="page"] {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ---------- Imágenes ---------- */

figure { margin: 0; }

figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
}

.band--dark figure img { border-color: rgba(244, 238, 225, 0.3); }

.caption {
  margin-top: 12px;
  font-size: 11.5px;
  line-height: 1.6;
  letter-spacing: 0.12em;
  color: var(--muted);
  text-transform: none;
}

.caption b {
  display: block;
  color: var(--ochre);
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  margin-bottom: 6px;
}

/* ---------- Pie ---------- */

.site-footer {
  max-width: 1180px;
  margin: 40px auto;
  padding: 0 var(--pad);
}

.footer-top {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 30px;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.footer-line {
  height: 1px;
  background: var(--line);
  margin: 16px 0 18px;
}

.footer-bottom {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px 40px;
  align-items: start;
}

.footer-bottom nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.footer-bottom nav a { color: var(--muted); text-decoration: none; }
.footer-bottom nav a:hover { color: var(--accent); text-decoration: underline; }

.footer-note {
  margin: 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- Adaptación ---------- */

@media (max-width: 900px) {
  .grid { grid-template-columns: 1fr; row-gap: 26px; }
  .c1-8, .c1-7, .c1-6, .c1-5,
  .c9-12, .c8-12, .c7-12, .c6-12,
  .full { grid-column: 1 / -1; }
  .band { padding: 26px var(--pad); }
  .sheet { margin-top: 18px; }
  .footer-bottom { grid-template-columns: 1fr; }
  body { font-size: 16px; }
  figure.narrow { max-width: 460px; }
}

@media (max-width: 520px) {
  .masthead nav ul { gap: 8px 16px; }
  .brand { letter-spacing: 0.2em; }
}