/* ============================================================
   base.css — reset, tipos, superficies de browser, utilidades
   ============================================================ */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

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

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.55;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

/* —— superficies del browser — pertenecen al diseño —— */
::selection { background: var(--green-soft); color: var(--ink); }
:focus-visible { outline: 2px solid var(--green); outline-offset: 2px; }
.caret, * { caret-color: var(--green); }

html { scrollbar-width: thin; scrollbar-color: var(--line-strong) transparent; }
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: var(--line-strong); border: 3px solid var(--paper); }
::-webkit-scrollbar-track { background: transparent; }

/* —— títulos —— */
h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 800;
  letter-spacing: -.028em;
  line-height: 1.02;
  text-wrap: balance;
}
p { max-width: 65ch; }

/* —— links —— */
a { color: inherit; }
.tlink {
  color: var(--green-ink);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: .18em;
  transition: color .2s var(--ease-out);
}
.tlink:hover { color: var(--ink); text-decoration-thickness: 2px; }

/* —— tipografía mono: solo datos —— */
.mono {
  font-family: var(--font-mono);
  font-size: var(--step--2);
  font-weight: 500;
  letter-spacing: .10em;
  text-transform: uppercase;
  color: var(--ink-65);
}
.mono--ink { color: var(--ink); }

/* —— imágenes —— */
img { display: block; max-width: 100%; height: auto; }

/* —— layout —— */
.container { width: min(var(--container), calc(100% - 2.5rem)); margin-inline: auto; }
.section { padding-block: var(--sp-5); }
.section-head { margin-bottom: var(--sp-3); }
.section-head h2 { font-size: var(--step-3); display: inline-block; position: relative; }
/* la regla verde ES el separador del sistema, no una decoración libre */
.section-head h2::after {
  content: '';
  position: absolute; left: 0; right: auto; bottom: -.5rem;
  width: 3.2rem; height: 3px; background: var(--green);
}

/* —— skip link —— */
.skip {
  position: absolute; left: -9999px; top: 0;
  background: var(--ink); color: var(--paper);
  padding: .6rem 1rem; z-index: 100;
}
.skip:focus-visible { left: 1rem; top: 1rem; }

/* delay de revelado por clase (reemplaza estilos inline) */
.d1 { --d: .06s; } .d2 { --d: .12s; } .d3 { --d: .2s; } .d4 { --d: .28s; }
.rv { opacity: 1; transform: none; }
.js .rv { opacity: 0; transform: translateY(var(--rv-y, 14px)); transition: opacity var(--dur) var(--ease-out), transform var(--dur) var(--ease-out); transition-delay: var(--d, 0s); }
.js .rv.on { opacity: 1; transform: none; }

/* —— motion —— */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .js .rv { opacity: 1; transform: none; }
}