/* ============================================================
   AMC — AM Consulting Marketing
   Design system: "The Audit" — an operator's document.
   Ink on paper. Highlighter for what matters. Red pen for
   what agencies say and shouldn't. Mono for the numbers.
   ============================================================ */

/* ---------- Tokens ---------- */
:root {
  /* Color */
  --ink: #0f1b2d;          /* primary text — blue-black ink */
  --ink-soft: #445063;     /* secondary text */
  --ink-faint: #6b7688;    /* tertiary / captions */
  --paper: #fbfbf8;        /* page */
  --paper-raised: #ffffff; /* cards */
  --paper-tint: #f2f3ee;   /* alternate sections */
  --marker: #ffd335;       /* highlighter yellow */
  --marker-soft: #fff3c2;  /* highlight wash */
  --blue: #1d4ed8;         /* links, primary actions */
  --blue-deep: #16389f;    /* hover */
  --green: #0b8a5c;        /* positive deltas (GSC green) */
  --red: #c4442a;          /* the red pen — strikethrough */
  --rule: #dcded6;         /* hairlines */
  --rule-dark: #b9bdb0;

  /* Type */
  --font-display: "Archivo", "Helvetica Neue", sans-serif;
  --font-body: "Public Sans", "Segoe UI", sans-serif;
  --font-mono: "Spline Sans Mono", "SF Mono", monospace;

  --text-hero: clamp(2.3rem, 6.5vw, 5.25rem);
  --text-h1: clamp(2.2rem, 4.5vw, 3.5rem);
  --text-h2: clamp(1.7rem, 3.2vw, 2.5rem);
  --text-h3: clamp(1.2rem, 1.8vw, 1.45rem);
  --text-body: 1.0625rem;
  --text-small: 0.9375rem;
  --text-label: 0.8125rem;

  /* Space */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --section: clamp(4.5rem, 10vw, 8rem);

  /* Layout */
  --max: 76rem;
  --gutter: clamp(1.25rem, 4vw, 2.5rem);
  --radius: 3px;

  /* Motion */
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --dur: 0.55s;
}

/* ---------- Reset & base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: var(--text-body);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}
img, svg { max-width: 100%; display: block; }
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-stretch: 112%;
  font-weight: 750;
  line-height: 1.06;
  letter-spacing: -0.015em;
  margin: 0 0 var(--space-4);
  text-wrap: balance;
}
h1 { font-size: var(--text-h1); }
h2 { font-size: var(--text-h2); }
h3 { font-size: var(--text-h3); font-stretch: 105%; font-weight: 700; }
p { margin: 0 0 var(--space-4); max-width: 65ch; }
a { color: var(--blue); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--blue-deep); }
:focus-visible { outline: 3px solid var(--blue); outline-offset: 2px; border-radius: 2px; }
::selection { background: var(--marker); color: var(--ink); }
strong { font-weight: 700; }
ul { padding-left: 1.2em; }

.wrap { max-width: var(--max); margin: 0 auto; padding-inline: var(--gutter); }
.section { padding-block: var(--section); }
.section--tint { background: var(--paper-tint); }
.section--ink { background: var(--ink); color: var(--paper); }
.section--ink h2, .section--ink h3 { color: #fff; }
.section--ink p { color: #c6cdd9; }

/* ---------- Utility type ---------- */
.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--ink-soft);
  display: flex;
  align-items: center;
  gap: 0.6em;
  margin-bottom: var(--space-4);
}
.eyebrow::before {
  content: "";
  width: 0.7em; height: 0.7em;
  background: var(--marker);
  flex: none;
}
.section--ink .eyebrow { color: #9aa6b8; }

.lede { font-size: 1.25rem; line-height: 1.55; color: var(--ink-soft); max-width: 42em; }
.section--ink .lede { color: #c6cdd9; }
.mono { font-family: var(--font-mono); }
.muted { color: var(--ink-faint); }

/* Highlighter swipe — animates in on reveal */
.hl {
  background-image: linear-gradient(120deg, var(--marker) 0%, var(--marker) 100%);
  background-repeat: no-repeat;
  background-size: 0% 42%;
  background-position: 0 78%;
  transition: background-size 0.7s var(--ease) 0.15s;
  padding-inline: 0.06em;
}
.is-visible .hl, .hl.is-visible { background-size: 100% 42%; }

/* The red pen — struck agency-speak, corrected in plain English.
   Mobile: native line-through (wraps safely). Desktop: animated strike bar. */
.redline { position: relative; }
.redline del {
  color: var(--ink-faint);
  text-decoration: line-through;
  text-decoration-color: var(--red);
  text-decoration-thickness: 0.09em;
}
@media (min-width: 52rem) {
  .redline { white-space: nowrap; }
  .redline del { text-decoration: none; position: relative; }
  .redline del::after {
    content: "";
    position: absolute;
    left: -2%; right: -2%; top: 52%;
    height: 0.09em; min-height: 3px;
    background: var(--red);
    transform: scaleX(0) rotate(-1.2deg);
    transform-origin: left center;
    transition: transform 0.5s var(--ease);
  }
  .is-visible .redline del::after { transform: scaleX(1) rotate(-1.2deg); }
}

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--rule);
}
.site-header .wrap {
  display: flex; align-items: center; justify-content: space-between;
  min-height: 4.25rem; gap: var(--space-6);
}
.logo {
  font-family: var(--font-display);
  font-stretch: 118%; font-weight: 800;
  font-size: 1.3rem; letter-spacing: -0.01em;
  color: var(--ink); text-decoration: none;
  display: flex; align-items: baseline; gap: 0.45em;
}
.logo .logo-mark { background: var(--marker); padding: 0 0.18em; }
.logo small {
  font-family: var(--font-mono); font-weight: 400; font-stretch: 100%;
  font-size: 0.6em; color: var(--ink-faint); letter-spacing: 0.05em;
}
.nav { display: flex; align-items: center; gap: clamp(1rem, 2.5vw, 2rem); }
.nav a {
  color: var(--ink-soft); text-decoration: none;
  font-size: var(--text-small); font-weight: 550;
  padding: 0.35em 0.1em;
  border-bottom: 2px solid transparent;
}
.nav a:hover { color: var(--ink); }
.nav a[aria-current="page"] { color: var(--ink); border-bottom-color: var(--marker); }
.nav-toggle { display: none; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 0.5em;
  font-family: var(--font-body); font-weight: 650; font-size: 1rem;
  padding: 0.8em 1.5em;
  border-radius: var(--radius);
  border: 2px solid var(--ink);
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.15s var(--ease), box-shadow 0.15s var(--ease), background 0.15s;
}
.btn--primary { background: var(--ink); color: #fff; }
.btn--primary:hover { background: #1a2c48; color: #fff; transform: translateY(-1px); box-shadow: 0 6px 18px rgba(15,27,45,0.18); }
.btn--ghost { background: transparent; color: var(--ink); }
.btn--ghost:hover { background: var(--marker-soft); color: var(--ink); }
.btn--marker { background: var(--marker); color: var(--ink); border-color: var(--ink); }
.btn--marker:hover { background: #ffdc5c; transform: translateY(-1px); box-shadow: 0 6px 18px rgba(15,27,45,0.15); }
.section--ink .btn--ghost { color: #fff; border-color: #fff; }
.section--ink .btn--ghost:hover { background: rgba(255,255,255,0.1); color: #fff; }
.btn .arrow { transition: transform 0.15s var(--ease); }
.btn:hover .arrow { transform: translateX(3px); }

/* ---------- Hero ---------- */
.hero { padding-block: clamp(4rem, 9vw, 7.5rem) clamp(3.5rem, 7vw, 6rem); }
.hero h1 {
  font-size: var(--text-hero);
  font-stretch: 116%; font-weight: 800;
  line-height: 1.0; letter-spacing: -0.02em;
  max-width: 12.5em;
}
.hero .lede { margin-top: var(--space-6); }
.hero-actions { display: flex; flex-wrap: wrap; gap: var(--space-4); margin-top: var(--space-8); }
.hero-note {
  margin-top: var(--space-6);
  font-family: var(--font-mono); font-size: var(--text-label);
  color: var(--ink-faint); letter-spacing: 0.03em;
}

/* ---------- Receipt / stat blocks ---------- */
.receipts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: var(--space-6);
}
.receipt {
  border: 1px solid var(--rule-dark);
  border-top: 3px solid var(--ink);
  background: var(--paper-raised);
  padding: var(--space-6);
  position: relative;
}
.receipt .stat {
  font-family: var(--font-mono);
  font-size: clamp(2.2rem, 4vw, 3.2rem);
  font-weight: 600; line-height: 1;
  letter-spacing: -0.03em;
  display: flex; align-items: baseline; gap: 0.15em;
}
.receipt .stat .delta { color: var(--green); font-size: 0.45em; font-weight: 500; }
.receipt .stat-label {
  margin-top: var(--space-3);
  font-weight: 650; font-size: var(--text-small);
}
.receipt .stat-source {
  margin-top: var(--space-2);
  font-family: var(--font-mono); font-size: 0.75rem;
  color: var(--ink-faint);
  border-top: 1px dashed var(--rule-dark);
  padding-top: var(--space-2);
}
.section--ink .receipt { background: transparent; border-color: #33415a; border-top-color: var(--marker); }
.section--ink .receipt .stat { color: #fff; }
.section--ink .receipt .stat-label { color: #c6cdd9; }
.section--ink .receipt .stat-source { color: #8390a5; border-top-color: #33415a; }

/* ---------- Cards ---------- */
.grid { display: grid; gap: var(--space-6); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(20rem, 100%), 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(17rem, 100%), 1fr)); }
.card {
  background: var(--paper-raised);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: var(--space-8);
  position: relative;
  transition: border-color 0.2s, box-shadow 0.2s, transform 0.2s var(--ease);
}
a.card { text-decoration: none; color: inherit; display: block; }
.card:hover { border-color: var(--ink); box-shadow: 0 10px 30px rgba(15,27,45,0.07); transform: translateY(-2px); }
.card h3 { margin-bottom: var(--space-3); }
.card .card-kicker {
  font-family: var(--font-mono); font-size: var(--text-label);
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-faint); margin-bottom: var(--space-3);
}
.card p { color: var(--ink-soft); font-size: var(--text-small); margin-bottom: 0; }
.card ul { margin: var(--space-4) 0 0; padding: 0; list-style: none; }
.card ul li {
  padding: 0.45em 0 0.45em 1.4em;
  position: relative;
  font-size: var(--text-small);
  color: var(--ink-soft);
  border-top: 1px dashed var(--rule);
}
.card ul li::before {
  content: "→"; position: absolute; left: 0;
  font-family: var(--font-mono); color: var(--ink);
}
.card .card-cta {
  margin-top: var(--space-4); display: inline-block;
  font-weight: 650; font-size: var(--text-small); color: var(--blue);
}

/* ---------- Case study rows ---------- */
.case {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: clamp(1.5rem, 4vw, 4rem);
  padding-block: var(--space-12);
  border-top: 1px solid var(--rule-dark);
  align-items: start;
}
.case:last-child { border-bottom: 1px solid var(--rule-dark); }
.case .case-tags { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: var(--space-4); }
.tag {
  font-family: var(--font-mono); font-size: 0.75rem;
  letter-spacing: 0.04em;
  border: 1px solid var(--rule-dark);
  padding: 0.25em 0.7em; border-radius: 99px;
  color: var(--ink-soft);
}
.case .case-stat {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 4.5vw, 3.4rem);
  font-weight: 600; line-height: 1.05; letter-spacing: -0.03em;
}
.case .case-stat .delta { color: var(--green); }
.case .case-statline { font-weight: 650; margin-top: var(--space-2); }
.case .case-source { font-family: var(--font-mono); font-size: 0.75rem; color: var(--ink-faint); margin-top: var(--space-3); }

/* ---------- Process / numbered steps ---------- */
.steps { counter-reset: step; display: grid; gap: 0; }
.step {
  counter-increment: step;
  display: grid;
  grid-template-columns: 4.5rem minmax(0, 16rem) 1fr;
  gap: var(--space-6);
  padding-block: var(--space-8);
  border-top: 1px solid var(--rule-dark);
}
.step::before {
  content: counter(step, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 1.1rem; color: var(--ink-faint);
  padding-top: 0.2em;
}
.step h3 { margin: 0; }
.step p { margin: 0; color: var(--ink-soft); }

/* ---------- FAQ ---------- */
.faq details { border-top: 1px solid var(--rule-dark); }
.faq details:last-child { border-bottom: 1px solid var(--rule-dark); }
.faq summary {
  cursor: pointer; list-style: none;
  display: flex; justify-content: space-between; align-items: center; gap: var(--space-4);
  padding: var(--space-6) 0;
  font-family: var(--font-display); font-stretch: 105%;
  font-weight: 700; font-size: 1.15rem;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; font-family: var(--font-mono); font-size: 1.4rem;
  color: var(--ink-faint); transition: transform 0.25s var(--ease); flex: none;
}
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { color: var(--ink-soft); padding-bottom: var(--space-6); margin: 0; }

/* ---------- Forms ---------- */
.form { display: grid; gap: var(--space-4); max-width: 36rem; }
.form label { font-weight: 650; font-size: var(--text-small); display: grid; gap: var(--space-2); }
.form input, .form textarea, .form select {
  font: inherit; color: var(--ink);
  background: var(--paper-raised);
  border: 1px solid var(--rule-dark);
  border-radius: var(--radius);
  padding: 0.7em 0.9em;
  width: 100%;
}
.form input:focus, .form textarea:focus, .form select:focus {
  outline: none; border-color: var(--blue);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--blue) 18%, transparent);
}

/* ---------- Marginalia / annotation ---------- */
.annotated { display: grid; grid-template-columns: minmax(0, 1fr) 14rem; gap: clamp(2rem, 5vw, 4rem); }
.margin-note {
  font-family: var(--font-mono); font-size: 0.8rem; line-height: 1.6;
  color: var(--ink-soft);
  border-left: 3px solid var(--marker);
  padding-left: var(--space-4);
  align-self: start;
  position: sticky; top: 6rem;
}

/* ---------- Footer ---------- */
.site-footer { background: var(--ink); color: #c6cdd9; padding-block: var(--space-16) var(--space-8); }
.site-footer a { color: #fff; }
.site-footer .footer-grid {
  display: grid; gap: var(--space-8);
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  padding-bottom: var(--space-12);
  border-bottom: 1px solid #33415a;
}
.site-footer h4 {
  color: #fff; font-size: var(--text-small);
  font-family: var(--font-mono); font-stretch: 100%; font-weight: 500;
  letter-spacing: 0.08em; text-transform: uppercase;
}
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: var(--space-2); }
.site-footer ul a { color: #c6cdd9; text-decoration: none; font-size: var(--text-small); }
.site-footer ul a:hover { color: #fff; }
.footer-meta {
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-4);
  padding-top: var(--space-8);
  font-family: var(--font-mono); font-size: 0.75rem; color: #8390a5;
}
.footer-meta a { color: inherit; text-decoration: none; }
.footer-meta a:hover { color: #fff; }

/* Form submission states */
.form-success {
  background: var(--marker-soft);
  border: 1px solid var(--rule-dark);
  border-left: 4px solid var(--marker);
  padding: var(--space-8);
  max-width: 36rem;
}
.form-success h3 { margin-bottom: var(--space-2); }
.form-success p { margin: 0; color: var(--ink-soft); }
.form-error { color: var(--red); font-size: var(--text-small); margin: 0; }
.form-error a { color: var(--red); font-weight: 650; }

/* ---------- Reveal animations ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease); }
.reveal.is-visible { opacity: 1; transform: none; }
.reveal-stagger > * { opacity: 0; transform: translateY(18px); transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease); }
.reveal-stagger.is-visible > * { opacity: 1; transform: none; }
.reveal-stagger.is-visible > *:nth-child(2) { transition-delay: 0.08s; }
.reveal-stagger.is-visible > *:nth-child(3) { transition-delay: 0.16s; }
.reveal-stagger.is-visible > *:nth-child(4) { transition-delay: 0.24s; }
.reveal-stagger.is-visible > *:nth-child(5) { transition-delay: 0.32s; }
.reveal-stagger.is-visible > *:nth-child(6) { transition-delay: 0.4s; }

/* ---------- Mobile ---------- */
@media (max-width: 52rem) {
  .hero h1 br, h1 br, h2 br { display: none; }
  h1, h2, h3, .stat { overflow-wrap: break-word; }
  .nav {
    position: fixed; inset: 4.25rem 0 auto 0;
    background: var(--paper);
    border-bottom: 1px solid var(--rule);
    flex-direction: column; align-items: stretch;
    padding: var(--space-4) var(--gutter) var(--space-6);
    gap: 0;
    display: none;
  }
  .nav.is-open { display: flex; }
  .nav a { padding: 0.8em 0; border-bottom: 1px solid var(--rule); font-size: 1.05rem; }
  .nav a[aria-current="page"] { border-bottom-color: var(--rule); }
  .nav .btn { margin-top: var(--space-4); justify-content: center; }
  .nav-toggle {
    display: inline-flex; align-items: center; justify-content: center;
    background: none; border: 1px solid var(--rule-dark); border-radius: var(--radius);
    width: 2.6rem; height: 2.6rem; cursor: pointer;
    font-family: var(--font-mono); font-size: 1.1rem; color: var(--ink);
  }
  .case { grid-template-columns: 1fr; }
  .step { grid-template-columns: 3rem 1fr; }
  .step p { grid-column: 2; }
  .annotated { grid-template-columns: 1fr; }
  .margin-note { position: static; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal, .reveal-stagger > * { opacity: 1; transform: none; transition: none; }
  .hl { background-size: 100% 42%; transition: none; }
  .redline del::after { transform: scaleX(1) rotate(-1.2deg); transition: none; }
  .btn, .card { transition: none; }
}

/* ---------- Print: it is a document, after all ---------- */
@media print {
  .site-header, .site-footer, .hero-actions { display: none; }
  body { background: #fff; }
}