@layer reset, tokens, base, layout, components, pages, utilities;

/* ============================================================ TOKENS */
@layer tokens {
  :root {
    --brand-grey: #919191;
    --brand-orange: #ff6b00;

    --font-display: "Sora", ui-sans-serif, system-ui, sans-serif;
    --font-body: "Inter", ui-sans-serif, system-ui, -apple-system, sans-serif;
    --font-mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, monospace;

    --step--1: clamp(.8rem, .77rem + .12vw, .875rem);
    --step-0: clamp(.95rem, .91rem + .2vw, 1.05rem);
    --step-1: clamp(1.12rem, 1.05rem + .35vw, 1.35rem);
    --step-2: clamp(1.4rem, 1.25rem + .7vw, 1.9rem);
    --step-3: clamp(1.8rem, 1.5rem + 1.4vw, 2.8rem);
    --step-4: clamp(2.3rem, 1.7rem + 2.8vw, 4.4rem);

    --shell: 1240px;
    --gutter: clamp(1.1rem, 4vw, 2.5rem);
    --block: clamp(4rem, 8vw, 7.5rem);

    --r-sm: 8px;
    --r-md: 14px;
    --r-lg: 22px;
    --r-xl: 32px;
    --r-full: 999px;

    --ease: cubic-bezier(.22, 1, .36, 1);
    --dur: .45s;

    --nav-h: 74px;
  }

  :root[data-theme="dark"] {
    --bg: #0e1013;
    --bg-2: #14171c;
    --bg-3: #191d23;
    --surface: rgba(255, 255, 255, .035);
    --surface-2: rgba(255, 255, 255, .06);
    --line: rgba(255, 255, 255, .09);
    --line-2: rgba(255, 255, 255, .16);
    --ink: #f2f4f7;
    --ink-2: #b7bec9;
    --ink-3: #7d8794;
    --accent: #ff7a1a;
    --accent-ink: #10120f;
    --accent-soft: rgba(255, 107, 0, .14);
    --glow: radial-gradient(60% 60% at 50% 0%, rgba(255, 107, 0, .18), transparent 70%);
    --shadow: 0 20px 60px -24px rgba(0, 0, 0, .85);
    --grid-line: rgba(255, 255, 255, .045);
    --header-bg: rgba(14, 16, 19, .78);
    color-scheme: dark;
  }

  :root[data-theme="light"] {
    --bg: #f7f7f8;
    --bg-2: #ffffff;
    --bg-3: #eeeff1;
    --surface: rgba(16, 18, 22, .025);
    --surface-2: rgba(16, 18, 22, .05);
    --line: rgba(16, 18, 22, .1);
    --line-2: rgba(16, 18, 22, .2);
    --ink: #14171c;
    --ink-2: #4a525e;
    --ink-3: #79818d;
    --accent: #e35c00;
    --accent-ink: #ffffff;
    --accent-soft: rgba(227, 92, 0, .1);
    --glow: radial-gradient(60% 60% at 50% 0%, rgba(255, 107, 0, .13), transparent 70%);
    --shadow: 0 18px 44px -22px rgba(16, 18, 22, .35);
    --grid-line: rgba(16, 18, 22, .05);
    --header-bg: rgba(247, 247, 248, .8);
    color-scheme: light;
  }
}

/* ============================================================ RESET */
@layer reset {
  *, *::before, *::after { box-sizing: border-box; }
  * { margin: 0; }
  html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 24px); }
  body { min-height: 100svh; -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
  img, svg, video { display: block; max-width: 100%; }
  input, button, textarea, select { font: inherit; color: inherit; }
  button { background: none; border: 0; cursor: pointer; }
  ul, ol { list-style: none; padding: 0; }
  a { color: inherit; text-decoration: none; }
  h1, h2, h3, h4 { text-wrap: balance; line-height: 1.1; }
  p { text-wrap: pretty; }
  :focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
  @media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  }
}

/* ============================================================ BASE */
@layer base {
  body {
    font-family: var(--font-body);
    font-size: var(--step-0);
    line-height: 1.65;
    color: var(--ink);
    background: var(--bg);
    overflow-x: hidden;
    transition: background-color .3s var(--ease), color .3s var(--ease);
  }
  body.is-locked { overflow: hidden; }

  .ico { width: 1.15em; height: 1.15em; flex: none; }
  .muted { color: var(--ink-3); }
  .accent { color: var(--accent); }

  .skip {
    position: fixed; inset-inline-start: 1rem; top: -100px; z-index: 200;
    background: var(--accent); color: var(--accent-ink);
    padding: .7rem 1.2rem; border-radius: var(--r-sm); font-weight: 600;
    transition: top .2s var(--ease);
  }
  .skip:focus { top: 1rem; }
}

/* ============================================================ LAYOUT */
@layer layout {
  .shell { width: min(100% - var(--gutter) * 2, var(--shell)); margin-inline: auto; }
  .section { padding-block: var(--block); position: relative; }
  .section--tight { padding-block: calc(var(--block) * .6); }
  .section--alt { background: var(--bg-2); border-block: 1px solid var(--line); }

  .grid { display: grid; gap: clamp(1rem, 2.4vw, 1.75rem); }
  .grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 290px), 1fr)); }
  .grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 340px), 1fr)); }
  .grid--4 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 220px), 1fr)); }

  .stack { display: grid; gap: 1rem; }
  .cluster { display: flex; flex-wrap: wrap; gap: .75rem; align-items: center; }
}

/* ============================================================ COMPONENTS */
@layer components {

  /* ---------- eyebrow & headings ---------- */
  .eyebrow {
    display: inline-flex; align-items: center; gap: .55rem;
    font-family: var(--font-mono); font-size: var(--step--1);
    letter-spacing: .16em; text-transform: uppercase; color: var(--accent);
    margin-bottom: 1rem;
  }
  .eyebrow::before { content: ""; width: 28px; height: 1px; background: currentColor; opacity: .6; }

  .h-xl { font-family: var(--font-display); font-size: var(--step-4); font-weight: 800; letter-spacing: -.03em; line-height: 1.02; }
  .h-lg { font-family: var(--font-display); font-size: var(--step-3); font-weight: 700; letter-spacing: -.025em; }
  .h-md { font-family: var(--font-display); font-size: var(--step-2); font-weight: 700; letter-spacing: -.02em; }
  .h-sm { font-family: var(--font-display); font-size: var(--step-1); font-weight: 600; letter-spacing: -.01em; }

  .lead { font-size: var(--step-1); color: var(--ink-2); line-height: 1.6; max-width: 62ch; }
  .body-text { color: var(--ink-2); max-width: 68ch; }

  .section-head { max-width: 760px; margin-bottom: clamp(2rem, 4vw, 3.5rem); }
  .section-head--center { margin-inline: auto; text-align: center; }
  .section-head--center .eyebrow::before { display: none; }

  /* ---------- buttons ---------- */
  .btn {
    --btn-bg: var(--surface-2); --btn-ink: var(--ink); --btn-line: var(--line-2);
    display: inline-flex; align-items: center; gap: .55rem;
    padding: .85rem 1.5rem; border-radius: var(--r-full);
    background: var(--btn-bg); color: var(--btn-ink);
    border: 1px solid var(--btn-line);
    font-weight: 600; font-size: var(--step-0); line-height: 1;
    transition: transform .25s var(--ease), background-color .25s var(--ease), border-color .25s var(--ease), box-shadow .25s var(--ease);
    white-space: nowrap;
  }
  .btn .ico { transition: transform .3s var(--ease); }
  .btn:hover { transform: translateY(-2px); }
  .btn:hover .ico { transform: translateX(3px); }
  .btn:active { transform: translateY(0); }
  .btn--primary { --btn-bg: var(--accent); --btn-ink: var(--accent-ink); --btn-line: transparent; box-shadow: 0 10px 30px -12px color-mix(in srgb, var(--accent) 70%, transparent); }
  .btn--primary:hover { box-shadow: 0 16px 38px -12px color-mix(in srgb, var(--accent) 80%, transparent); }
  .btn--ghost { --btn-bg: transparent; }
  .btn--ghost:hover { --btn-bg: var(--surface-2); }
  .btn--sm { padding: .6rem 1.1rem; font-size: var(--step--1); }
  .btn--block { width: 100%; justify-content: center; }

  .icon-btn {
    width: 42px; height: 42px; display: grid; place-items: center;
    border-radius: var(--r-full); border: 1px solid var(--line);
    background: var(--surface); color: var(--ink-2);
    transition: color .25s var(--ease), border-color .25s var(--ease), background-color .25s var(--ease);
  }
  .icon-btn:hover { color: var(--accent); border-color: var(--accent); }
  .icon-btn .ico { width: 19px; height: 19px; position: absolute; transition: opacity .25s var(--ease), transform .35s var(--ease); }
  .icon-btn { position: relative; }
  :root[data-theme="dark"] .ico--sun { opacity: 1; transform: rotate(0); }
  :root[data-theme="dark"] .ico--moon { opacity: 0; transform: rotate(-90deg); }
  :root[data-theme="light"] .ico--sun { opacity: 0; transform: rotate(90deg); }
  :root[data-theme="light"] .ico--moon { opacity: 1; transform: rotate(0); }

  /* ---------- chips / tags ---------- */
  .chip {
    display: inline-flex; align-items: center; gap: .4rem;
    padding: .35rem .8rem; border-radius: var(--r-full);
    border: 1px solid var(--line); background: var(--surface);
    font-family: var(--font-mono); font-size: var(--step--1);
    letter-spacing: .05em; color: var(--ink-2);
  }
  .chip--accent { border-color: color-mix(in srgb, var(--accent) 45%, transparent); background: var(--accent-soft); color: var(--accent); }

  /* ---------- header ---------- */
  .site-header { position: sticky; top: 0; z-index: 100; background: var(--header-bg); backdrop-filter: blur(16px) saturate(160%); border-bottom: 1px solid transparent; transition: border-color .3s var(--ease), box-shadow .3s var(--ease); }
  .site-header.is-stuck { border-bottom-color: var(--line); box-shadow: 0 8px 30px -20px rgba(0, 0, 0, .6); }

  .topbar { background: var(--bg-2); border-bottom: 1px solid var(--line); font-size: var(--step--1); color: var(--ink-3); }
  .topbar__in { display: flex; align-items: center; gap: 1.1rem; height: 38px; overflow-x: auto; scrollbar-width: none; }
  .topbar__in::-webkit-scrollbar { display: none; }
  .topbar__item { display: inline-flex; align-items: center; gap: .45rem; white-space: nowrap; transition: color .2s var(--ease); }
  .topbar__item .ico { width: 15px; height: 15px; color: var(--accent); }
  a.topbar__item:hover { color: var(--ink); }
  .topbar__sep { flex: 1; }
  @media (max-width: 860px) { .topbar { display: none; } }

  .nav { display: flex; align-items: center; gap: 1.25rem; height: var(--nav-h); }
  .brand { display: inline-flex; align-items: center; gap: .7rem; }
  .brand img { width: 46px; height: 46px; object-fit: contain; }
  .brand__text { display: grid; line-height: 1.1; }
  .brand__text strong { font-family: var(--font-display); font-size: 1.22rem; font-weight: 800; letter-spacing: .1em; }
  .brand__text small { font-size: .62rem; letter-spacing: .22em; text-transform: uppercase; color: var(--ink-3); white-space: nowrap; }
  @media (max-width: 420px) { .nav .brand__text small { display: none; } }

  .nav__links { display: flex; gap: .25rem; margin-inline-start: auto; }
  .nav__links a {
    position: relative; padding: .55rem .9rem; border-radius: var(--r-full);
    font-size: var(--step--1); font-weight: 500; color: var(--ink-2); letter-spacing: .01em;
    transition: color .22s var(--ease), background-color .22s var(--ease);
  }
  .nav__links a:hover { color: var(--ink); background: var(--surface-2); }
  .nav__links a[aria-current="page"] { color: var(--ink); background: var(--surface-2); }
  .nav__links a[aria-current="page"]::after {
    content: ""; position: absolute; left: 50%; translate: -50% 0; bottom: .18rem;
    width: 16px; height: 2px; border-radius: 2px; background: var(--accent);
  }

  .nav__actions { display: flex; align-items: center; gap: .6rem; }
  .burger { display: none; width: 42px; height: 42px; border-radius: var(--r-full); border: 1px solid var(--line); background: var(--surface); place-items: center; gap: 5px; flex-direction: column; }
  .burger span { display: block; width: 17px; height: 2px; border-radius: 2px; background: var(--ink); transition: transform .3s var(--ease), opacity .2s var(--ease); }
  .burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
  .burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  .scroll-progress { position: absolute; left: 0; bottom: -1px; height: 2px; width: 0; background: linear-gradient(90deg, var(--accent), color-mix(in srgb, var(--accent) 40%, var(--brand-grey))); transition: width .1s linear; }

  @media (max-width: 1020px) {
    .burger { display: flex; }
    .nav__cta { display: none; }
    /* Anclado al header (sticky) para no tapar la barra de contacto superior. */
    .nav__links {
      position: absolute; top: 100%; inset-inline: 0; margin: 0;
      flex-direction: column; gap: 0; padding: 1rem var(--gutter) 2rem;
      background: var(--bg-2); border-bottom: 1px solid var(--line);
      box-shadow: var(--shadow);
      transform: translateY(-12px); opacity: 0; visibility: hidden; pointer-events: none;
      transition: opacity .3s var(--ease), transform .3s var(--ease), visibility .3s;
      max-height: calc(100svh - var(--nav-h)); overflow-y: auto;
    }
    .nav__links.is-open { transform: translateY(0); opacity: 1; visibility: visible; pointer-events: auto; }
    .nav__links a { padding: .95rem .5rem; font-size: var(--step-1); border-radius: 0; border-bottom: 1px solid var(--line); }
    .nav__links a[aria-current="page"]::after { left: .5rem; translate: 0 0; bottom: .7rem; }
  }

  /* ---------- hero ---------- */
  .hero { position: relative; overflow: clip; padding-block: clamp(3.5rem, 8vw, 7rem) clamp(3rem, 6vw, 5.5rem); }
  .hero::before {
    content: ""; position: absolute; inset: 0; z-index: -2;
    background-image: linear-gradient(var(--grid-line) 1px, transparent 1px), linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
    background-size: 64px 64px;
    mask-image: radial-gradient(120% 90% at 50% 0%, #000 30%, transparent 78%);
  }
  .hero::after { content: ""; position: absolute; inset: 0; z-index: -1; background: var(--glow); pointer-events: none; }
  .hero__wave { position: absolute; inset-inline: 0; bottom: 0; height: 220px; width: 100%; z-index: -1; opacity: .5; }

  .hero__grid { display: grid; gap: clamp(2rem, 5vw, 3.5rem); grid-template-columns: 1fr; align-items: center; }
  @media (min-width: 1080px) { .hero__grid { grid-template-columns: 1.15fr .85fr; } }

  .hero__title { margin-block: .4rem 1.4rem; }
  .hero__title em { font-style: normal; color: var(--accent); }
  .hero__actions { margin-top: 2rem; }
  .hero__meta { display: flex; flex-wrap: wrap; gap: 1.5rem 2.5rem; margin-top: 2.75rem; padding-top: 1.75rem; border-top: 1px solid var(--line); }
  .hero__meta div { display: grid; gap: .15rem; }
  .hero__meta b { font-family: var(--font-display); font-size: var(--step-2); font-weight: 700; letter-spacing: -.02em; }
  .hero__meta span { font-size: var(--step--1); color: var(--ink-3); max-width: 22ch; line-height: 1.4; }

  .hero__panel {
    position: relative; border: 1px solid var(--line); border-radius: var(--r-xl);
    background: linear-gradient(160deg, var(--surface-2), transparent 60%), var(--bg-2);
    padding: clamp(1.25rem, 3vw, 1.9rem); box-shadow: var(--shadow);
  }
  .hero__panel h2 { font-family: var(--font-mono); font-size: var(--step--1); letter-spacing: .18em; text-transform: uppercase; color: var(--ink-3); margin-bottom: 1.1rem; }
  .method-list { display: grid; gap: .5rem; }
  .method-row {
    display: grid; grid-template-columns: 58px 1fr auto; align-items: center; gap: .85rem;
    padding: .7rem .85rem; border-radius: var(--r-md); border: 1px solid transparent;
    transition: background-color .25s var(--ease), border-color .25s var(--ease), transform .25s var(--ease);
  }
  .method-row:hover { background: var(--surface); border-color: var(--line); transform: translateX(3px); }
  .method-row__code { font-family: var(--font-mono); font-weight: 700; font-size: .8rem; letter-spacing: .04em; color: var(--accent); background: var(--accent-soft); border-radius: var(--r-sm); padding: .3rem .1rem; text-align: center; }
  .method-row__name { font-size: var(--step--1); font-weight: 500; line-height: 1.35; }
  .method-row__kind { font-family: var(--font-mono); font-size: .66rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3); }

  /* ---------- marquee ---------- */
  .marquee { overflow: hidden; border-block: 1px solid var(--line); background: var(--bg-2); padding-block: 1.1rem; -webkit-mask-image: linear-gradient(90deg, transparent, #000 12%, #000 88%, transparent); mask-image: linear-gradient(90deg, transparent, #000 12%, #000 88%, transparent); }
  .marquee__track { display: flex; gap: 3rem; width: max-content; animation: slide 38s linear infinite; }
  .marquee:hover .marquee__track { animation-play-state: paused; }
  .marquee__item { font-family: var(--font-mono); font-size: var(--step--1); letter-spacing: .13em; text-transform: uppercase; color: var(--ink-3); white-space: nowrap; display: inline-flex; align-items: center; gap: 3rem; }
  .marquee__item::after { content: ""; width: 4px; height: 4px; border-radius: 50%; background: var(--accent); opacity: .7; }
  @keyframes slide { to { transform: translateX(-50%); } }

  /* ---------- cards ---------- */
  .card {
    position: relative; display: flex; flex-direction: column; gap: .9rem;
    padding: clamp(1.4rem, 3vw, 2rem); border-radius: var(--r-lg);
    border: 1px solid var(--line); background: var(--bg-2);
    transition: border-color .3s var(--ease), transform .3s var(--ease), box-shadow .3s var(--ease);
    overflow: hidden;
  }
  .card::before {
    content: ""; position: absolute; inset: 0; opacity: 0; pointer-events: none;
    background: radial-gradient(420px circle at var(--mx, 50%) var(--my, 0%), var(--accent-soft), transparent 60%);
    transition: opacity .35s var(--ease);
  }
  .card:hover { border-color: var(--line-2); transform: translateY(-4px); box-shadow: var(--shadow); }
  .card:hover::before { opacity: 1; }
  .card > * { position: relative; }

  .card__icon { width: 48px; height: 48px; display: grid; place-items: center; border-radius: var(--r-md); background: var(--accent-soft); color: var(--accent); border: 1px solid color-mix(in srgb, var(--accent) 25%, transparent); }
  .card__icon .ico { width: 24px; height: 24px; }
  .card h3 { font-family: var(--font-display); font-size: var(--step-1); font-weight: 700; letter-spacing: -.015em; }
  .card p { color: var(--ink-2); font-size: var(--step-0); }
  .card__link { margin-top: auto; padding-top: .5rem; display: inline-flex; align-items: center; gap: .45rem; font-weight: 600; font-size: var(--step--1); color: var(--accent); }
  .card__link .ico { transition: transform .3s var(--ease); }
  .card:hover .card__link .ico { transform: translateX(4px); }
  .card--link { cursor: pointer; }

  .card__index { position: absolute; top: 1rem; right: 1.2rem; font-family: var(--font-mono); font-size: 2.6rem; font-weight: 700; color: var(--ink); opacity: .05; line-height: 1; }

  /* ---------- ticked list ---------- */
  .ticks { display: grid; gap: .65rem; }
  .ticks li { display: grid; grid-template-columns: 20px 1fr; gap: .7rem; align-items: start; color: var(--ink-2); font-size: var(--step-0); line-height: 1.5; }
  .ticks .ico { width: 18px; height: 18px; margin-top: .28em; color: var(--accent); }
  .ticks--sm li { font-size: var(--step--1); }

  /* ---------- stats ---------- */
  .stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 190px), 1fr)); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--r-lg); overflow: hidden; }
  .stat { background: var(--bg-2); padding: clamp(1.4rem, 3vw, 2.1rem); display: grid; gap: .35rem; }
  .stat b { font-family: var(--font-display); font-size: clamp(2rem, 4vw, 3rem); font-weight: 800; letter-spacing: -.03em; line-height: 1; background: linear-gradient(180deg, var(--ink), var(--ink-3)); -webkit-background-clip: text; background-clip: text; color: transparent; }
  .stat span { font-size: var(--step--1); color: var(--ink-3); line-height: 1.45; }

  /* ---------- steps / timeline ---------- */
  .steps { display: grid; gap: clamp(1rem, 2.5vw, 1.5rem); grid-template-columns: repeat(auto-fit, minmax(min(100%, 240px), 1fr)); counter-reset: step; }
  .step { position: relative; padding: 1.6rem 1.4rem; border-radius: var(--r-lg); border: 1px solid var(--line); background: var(--bg-2); }
  .step__n { font-family: var(--font-mono); font-size: var(--step--1); font-weight: 700; letter-spacing: .12em; color: var(--accent); display: block; margin-bottom: .7rem; }
  .step h3 { font-family: var(--font-display); font-size: var(--step-1); margin-bottom: .4rem; }
  .step p { color: var(--ink-2); font-size: var(--step--1); }
  .step::after { content: ""; position: absolute; top: 2.1rem; right: -1px; width: 8px; height: 8px; border-radius: 50%; background: var(--accent); opacity: 0; }

  /* ---------- tabs ---------- */
  .tabs__list { display: inline-flex; gap: .3rem; padding: .35rem; border-radius: var(--r-full); border: 1px solid var(--line); background: var(--surface); margin-bottom: 1.75rem; flex-wrap: wrap; }
  .tabs__btn { padding: .65rem 1.4rem; border-radius: var(--r-full); font-size: var(--step--1); font-weight: 600; color: var(--ink-3); transition: color .25s var(--ease), background-color .25s var(--ease); }
  .tabs__btn[aria-selected="true"] { background: var(--accent); color: var(--accent-ink); }
  .tabs__panel[hidden] { display: none; }
  .tabs__panel { animation: fadeUp .4s var(--ease) both; }
  @keyframes fadeUp { from { opacity: 0; transform: translateY(10px); } }

  /* ---------- accordion ---------- */
  .acc { border: 1px solid var(--line); border-radius: var(--r-lg); overflow: hidden; background: var(--bg-2); }
  .acc__item + .acc__item { border-top: 1px solid var(--line); }
  .acc__btn { width: 100%; display: flex; align-items: center; gap: 1rem; padding: 1.25rem clamp(1rem, 3vw, 1.6rem); text-align: start; font-family: var(--font-display); font-size: var(--step-1); font-weight: 600; letter-spacing: -.015em; transition: background-color .25s var(--ease); }
  .acc__btn:hover { background: var(--surface); }
  .acc__btn .card__icon { width: 38px; height: 38px; flex: none; border-radius: var(--r-sm); }
  .acc__btn .card__icon .ico { width: 19px; height: 19px; }
  .acc__title { flex: 1; }
  .acc__sign { width: 26px; height: 26px; flex: none; position: relative; border-radius: 50%; border: 1px solid var(--line-2); }
  .acc__sign::before, .acc__sign::after { content: ""; position: absolute; inset: 50% 25%; height: 1.5px; background: currentColor; translate: 0 -50%; border-radius: 2px; transition: transform .3s var(--ease), opacity .3s var(--ease); }
  .acc__sign::after { transform: rotate(90deg); }
  .acc__btn[aria-expanded="true"] .acc__sign { color: var(--accent); border-color: var(--accent); }
  .acc__btn[aria-expanded="true"] .acc__sign::after { transform: rotate(0); opacity: 0; }
  .acc__body { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .35s var(--ease); }
  .acc__body.is-open { grid-template-rows: 1fr; }
  .acc__inner { overflow: hidden; }
  .acc__inner > div { padding: 0 clamp(1rem, 3vw, 1.6rem) 1.6rem clamp(1rem, 3vw, 1.6rem); }

  /* ---------- course table ---------- */
  .courses { display: grid; gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--r-lg); overflow: hidden; }
  .course { display: grid; grid-template-columns: 76px 1fr auto; gap: 1rem; align-items: center; padding: 1.1rem 1.25rem; background: var(--bg-2); transition: background-color .25s var(--ease); }
  .course:hover { background: var(--bg-3); }
  .course__code { font-family: var(--font-mono); font-weight: 700; font-size: .82rem; color: var(--accent); background: var(--accent-soft); border: 1px solid color-mix(in srgb, var(--accent) 22%, transparent); border-radius: var(--r-sm); padding: .35rem .2rem; text-align: center; }
  .course__name { font-weight: 500; }
  .course__levels { font-family: var(--font-mono); font-size: var(--step--1); color: var(--ink-3); white-space: nowrap; }
  @media (max-width: 560px) {
    .course { grid-template-columns: 66px 1fr; }
    .course__levels { grid-column: 2; }
  }

  /* ---------- callout ---------- */
  .callout { display: grid; gap: .5rem; padding: clamp(1.2rem, 3vw, 1.7rem); border-radius: var(--r-lg); border: 1px solid color-mix(in srgb, var(--accent) 28%, transparent); background: var(--accent-soft); }
  .callout strong { font-family: var(--font-display); }
  .callout p { color: var(--ink-2); font-size: var(--step--1); }

  /* ---------- CTA band ---------- */
  .cta {
    position: relative; overflow: hidden; border-radius: var(--r-xl);
    border: 1px solid var(--line); background: var(--bg-2);
    padding: clamp(2rem, 5vw, 3.75rem); text-align: center;
  }
  .cta::before {
    content: ""; position: absolute; inset: 0; z-index: 0;
    background: radial-gradient(70% 120% at 50% 0%, var(--accent-soft), transparent 70%);
  }
  .cta > * { position: relative; z-index: 1; }
  .cta p { margin-inline: auto; }
  .cta .cluster { justify-content: center; margin-top: 1.9rem; }

  /* ---------- forms ---------- */
  .field { display: grid; gap: .45rem; }
  .field > label { font-size: var(--step--1); font-weight: 600; color: var(--ink-2); }
  .field .req { color: var(--accent); }
  .input, .textarea, .select {
    width: 100%; padding: .85rem 1rem; border-radius: var(--r-md);
    border: 1px solid var(--line-2); background: var(--bg);
    color: var(--ink); font-size: var(--step-0);
    transition: border-color .25s var(--ease), box-shadow .25s var(--ease), background-color .25s var(--ease);
  }
  .input::placeholder, .textarea::placeholder { color: var(--ink-3); }
  .input:focus, .textarea:focus, .select:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }
  .textarea { resize: vertical; min-height: 148px; line-height: 1.6; }
  .field__error { font-size: var(--step--1); color: #ff6b6b; }
  .field.has-error .input, .field.has-error .textarea { border-color: #ff6b6b; }
  .hp { position: absolute; left: -9999px; opacity: 0; }

  .checks { display: flex; flex-wrap: wrap; gap: .55rem; }
  .check input { position: absolute; opacity: 0; width: 0; height: 0; }
  .check span {
    display: inline-flex; align-items: center; gap: .45rem; cursor: pointer;
    padding: .55rem 1rem; border-radius: var(--r-full);
    border: 1px solid var(--line-2); background: var(--surface);
    font-size: var(--step--1); font-weight: 500; color: var(--ink-2);
    transition: all .22s var(--ease);
  }
  .check span::before { content: ""; width: 14px; height: 14px; border-radius: 4px; border: 1.5px solid var(--line-2); transition: all .22s var(--ease); }
  .check input:checked + span { border-color: var(--accent); color: var(--accent); background: var(--accent-soft); }
  .check input:checked + span::before { background: var(--accent); border-color: var(--accent); box-shadow: inset 0 0 0 2px var(--bg-2); }
  .check input:focus-visible + span { outline: 2px solid var(--accent); outline-offset: 3px; }

  .alert { display: flex; gap: .75rem; align-items: start; padding: 1rem 1.2rem; border-radius: var(--r-md); border: 1px solid var(--line-2); background: var(--surface); font-size: var(--step--1); }
  .alert .ico { margin-top: .15em; flex: none; }
  .alert--ok { border-color: color-mix(in srgb, #22c55e 45%, transparent); background: color-mix(in srgb, #22c55e 10%, transparent); color: var(--ink); }
  .alert--ok .ico { color: #22c55e; }
  .alert--bad { border-color: color-mix(in srgb, #ef4444 45%, transparent); background: color-mix(in srgb, #ef4444 10%, transparent); }
  .alert--bad .ico { color: #ef4444; }

  /* ---------- footer ---------- */
  .site-footer { border-top: 1px solid var(--line); background: var(--bg-2); padding-top: clamp(3rem, 6vw, 4.5rem); margin-top: clamp(3rem, 6vw, 5rem); }
  .footer__grid { display: grid; gap: clamp(2rem, 4vw, 3rem); grid-template-columns: repeat(auto-fit, minmax(min(100%, 230px), 1fr)); padding-bottom: 3rem; }
  .footer__brand { max-width: 320px; display: grid; gap: 1.1rem; align-content: start; }
  .footer__lead { font-size: var(--step--1); color: var(--ink-2); line-height: 1.6; }
  .footer__social { display: flex; gap: .6rem; }
  .footer__social a { width: 40px; height: 40px; display: grid; place-items: center; border-radius: var(--r-full); border: 1px solid var(--line); color: var(--ink-3); transition: all .25s var(--ease); }
  .footer__social a:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }
  .footer__social .ico { width: 18px; height: 18px; }
  .footer__col h3 { font-family: var(--font-mono); font-size: var(--step--1); letter-spacing: .15em; text-transform: uppercase; color: var(--ink-3); margin-bottom: 1.1rem; font-weight: 500; }
  .footer__col ul { display: grid; gap: .65rem; font-size: var(--step--1); }
  .footer__col a { color: var(--ink-2); transition: color .2s var(--ease); }
  .footer__col a:hover { color: var(--accent); }
  .footer__contact li { display: grid; grid-template-columns: 18px 1fr; gap: .7rem; align-items: start; color: var(--ink-2); }
  .footer__contact .ico { width: 16px; height: 16px; margin-top: .25em; color: var(--accent); }
  .footer__claims li { position: relative; padding-inline-start: 1rem; color: var(--ink-2); line-height: 1.5; }
  .footer__claims li::before { content: ""; position: absolute; inset-inline-start: 0; top: .62em; width: 5px; height: 5px; border-radius: 50%; background: var(--accent); }
  .footer__bottom { display: flex; flex-wrap: wrap; gap: .6rem 1.5rem; justify-content: space-between; padding-block: 1.5rem; border-top: 1px solid var(--line); font-size: var(--step--1); color: var(--ink-3); }

  /* ---------- whatsapp fab ---------- */
  .wa-fab {
    position: fixed; right: clamp(1rem, 3vw, 1.75rem); bottom: clamp(1rem, 3vw, 1.75rem); z-index: 90;
    width: 54px; height: 54px; display: grid; place-items: center; border-radius: 50%;
    background: #25d366; color: #08130b; box-shadow: 0 14px 34px -12px rgba(37, 211, 102, .7);
    transition: transform .3s var(--ease);
  }
  .wa-fab:hover { transform: scale(1.08) translateY(-2px); }
  .wa-fab svg { width: 28px; height: 28px; fill: currentColor; }

  /* ---------- reveal ---------- */
  /* Sólo se ocultan si el JS arrancó: sin JS el contenido siempre es visible. */
  .js .reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
  .js .reveal.is-in { opacity: 1; transform: none; }
  @media (prefers-reduced-motion: reduce) { .js .reveal { opacity: 1; transform: none; } }
}

/* ============================================================ PAGES */
@layer pages {
  /* page header */
  .page-head { position: relative; overflow: clip; padding-block: clamp(3rem, 7vw, 5rem) clamp(2rem, 4vw, 3rem); border-bottom: 1px solid var(--line); }
  .page-head::before {
    content: ""; position: absolute; inset: 0; z-index: -1;
    background-image: linear-gradient(var(--grid-line) 1px, transparent 1px), linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
    background-size: 48px 48px;
    mask-image: radial-gradient(110% 100% at 20% 0%, #000 20%, transparent 75%);
  }
  .crumbs { display: flex; gap: .5rem; align-items: center; font-size: var(--step--1); color: var(--ink-3); margin-bottom: 1.1rem; }
  .crumbs a:hover { color: var(--accent); }
  .crumbs span { opacity: .5; }

  /* verifier */
  .verify { display: grid; gap: clamp(1.5rem, 4vw, 2.5rem); grid-template-columns: 1fr; }
  @media (min-width: 940px) { .verify { grid-template-columns: 1.1fr .9fr; align-items: start; } }
  .verify__card { padding: clamp(1.4rem, 3.5vw, 2.2rem); border-radius: var(--r-xl); border: 1px solid var(--line); background: var(--bg-2); box-shadow: var(--shadow); }
  .verify__form { display: flex; gap: .6rem; flex-wrap: wrap; }
  .verify__form .field { flex: 1 1 240px; }
  .verify__form .input { font-family: var(--font-mono); letter-spacing: .08em; text-transform: uppercase; }
  .verify__result { margin-top: 1.5rem; }
  .verify__result:empty { display: none; }

  .cert { border: 1px solid var(--line); border-radius: var(--r-lg); overflow: hidden; }
  .cert__head { display: flex; flex-wrap: wrap; align-items: center; gap: .75rem; padding: 1rem 1.25rem; border-bottom: 1px solid var(--line); }
  .cert__badge { display: inline-flex; align-items: center; gap: .45rem; padding: .35rem .85rem; border-radius: var(--r-full); font-size: var(--step--1); font-weight: 700; letter-spacing: .04em; text-transform: uppercase; }
  .cert__badge--ok { background: color-mix(in srgb, #22c55e 18%, transparent); color: #22c55e; }
  .cert__badge--bad { background: color-mix(in srgb, #ef4444 18%, transparent); color: #ef4444; }
  .cert__folio { margin-inline-start: auto; font-family: var(--font-mono); font-size: var(--step--1); color: var(--ink-3); }
  .cert__grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 165px), 1fr)); gap: 1px; background: var(--line); }
  .cert__cell { background: var(--bg-2); padding: 1rem 1.25rem; display: grid; gap: .25rem; }
  .cert__cell dt { font-family: var(--font-mono); font-size: .68rem; letter-spacing: .14em; text-transform: uppercase; color: var(--ink-3); }
  .cert__cell dd { margin: 0; font-weight: 600; }

  .spinner { width: 17px; height: 17px; border-radius: 50%; border: 2px solid currentColor; border-top-color: transparent; animation: spin .7s linear infinite; }
  @keyframes spin { to { transform: rotate(360deg); } }

  /* contact */
  .contact { display: grid; gap: clamp(1.75rem, 4vw, 3rem); grid-template-columns: 1fr; }
  @media (min-width: 960px) { .contact { grid-template-columns: 1.2fr .8fr; align-items: start; } }
  .contact__form { display: grid; gap: 1.15rem; padding: clamp(1.4rem, 3.5vw, 2.2rem); border-radius: var(--r-xl); border: 1px solid var(--line); background: var(--bg-2); box-shadow: var(--shadow); }
  .contact__row { display: grid; gap: 1.15rem; grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr)); }
  .contact__aside { display: grid; gap: 1.25rem; align-content: start; }
  .info-card { padding: 1.4rem 1.5rem; border-radius: var(--r-lg); border: 1px solid var(--line); background: var(--bg-2); display: grid; gap: 1rem; }
  .info-card h3 { font-family: var(--font-mono); font-size: var(--step--1); letter-spacing: .15em; text-transform: uppercase; color: var(--ink-3); font-weight: 500; }
  .info-list { display: grid; gap: .9rem; }
  .info-list li { display: grid; grid-template-columns: 34px 1fr; gap: .8rem; align-items: center; }
  .info-list .card__icon { width: 34px; height: 34px; border-radius: var(--r-sm); }
  .info-list .card__icon .ico { width: 17px; height: 17px; }
  .info-list b { display: block; font-size: var(--step--1); font-weight: 600; }
  .info-list span { font-size: var(--step--1); color: var(--ink-3); }

  /* error page */
  .err { min-height: 52svh; display: grid; place-items: center; text-align: center; padding-block: var(--block); }
  .err__code { font-family: var(--font-display); font-size: clamp(5rem, 18vw, 11rem); font-weight: 800; line-height: 1; letter-spacing: -.05em; background: linear-gradient(180deg, var(--ink), transparent 115%); -webkit-background-clip: text; background-clip: text; color: transparent; }
}

/* ============================================================ UTILITIES */
@layer utilities {
  .center { text-align: center; }
  .mt-1 { margin-top: .75rem; } .mt-2 { margin-top: 1.5rem; } .mt-3 { margin-top: 2.5rem; }
  .mb-2 { margin-bottom: 1.5rem; }
  .sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
  [hidden] { display: none !important; }
}