/* ==========================================================
   Swap Globals
   Minimal technical-publishing direction
   Paper white / ink / one accent. No shadows, no gradients.
   ========================================================== */

/* ---------- Tokens ---------- */
:root {
  --paper:      #ffffff;
  --surface:    #f5f5f3;
  --surface-2:  #ecece9;
  --ink:        #15171c;
  --ink-2:      #5b5f68;
  --ink-3:      #8a8e96;
  --rule:       #e4e4e0;
  --accent:     #1b4d3e;
  --accent-2:   #133429;
  --accent-soft:#ecf1ee;

  --sans: "IBM Plex Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;

  --wrap: 1120px;
  --gutter: 1.5rem;
  --section: 6rem;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}

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

h1, h2, h3, h4, p, ul, ol, figure { margin: 0; }
ul, ol { padding: 0; list-style: none; }

a { color: inherit; text-decoration: none; }

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

/* ---------- Layout ---------- */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section); }
.section + .section { padding-top: 0; }
.section--tint { background: var(--surface); }
.section--tint + .section { padding-top: var(--section); }

.rule { height: 1px; background: var(--rule); border: 0; margin: 0; }

/* ---------- Typography ---------- */
.display {
  font-size: clamp(2.25rem, 6.2vw, 4rem);
  line-height: 1.04;
  letter-spacing: -0.035em;
  font-weight: 500;
  max-width: 16ch;
}

.h2 {
  font-size: clamp(1.5rem, 3.2vw, 2.125rem);
  line-height: 1.15;
  letter-spacing: -0.025em;
  font-weight: 500;
  max-width: 20ch;
}

.h3 {
  font-size: 1.0625rem;
  line-height: 1.35;
  letter-spacing: -0.01em;
  font-weight: 600;
}

.lede {
  font-size: 1.0625rem;
  color: var(--ink-2);
  max-width: 54ch;
}

.small { font-size: 0.9375rem; color: var(--ink-2); }

/* Monospace label — the site's structural voice */
.label {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
}

/* Numbered section marker (signature device) */
.marker {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.marker::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--rule);
}

.marker .num {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.marker .name {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.8rem 1.4rem;
  font-family: var(--sans);
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: -0.005em;
  border: 1px solid var(--ink);
  border-radius: 2px;
  background: var(--ink);
  color: var(--paper);
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}

.btn:hover { background: var(--accent); border-color: var(--accent); }

.btn--ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--rule);
}

.btn--ghost:hover {
  background: transparent;
  color: var(--accent);
  border-color: var(--accent);
}

.btn--light {
  background: var(--paper);
  color: var(--ink);
  border-color: var(--paper);
}

.btn--light:hover { background: var(--accent-soft); border-color: var(--accent-soft); color: var(--accent-2); }

.arrow-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--accent);
  border-bottom: 1px solid transparent;
  padding-bottom: 1px;
  transition: border-color 0.18s ease;
}

.arrow-link:hover { border-bottom-color: var(--accent); }
.arrow-link::after { content: "\2192"; font-family: var(--mono); }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--rule);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.brand { display: flex; align-items: center; gap: 0.7rem; }

.brand img {
  width: 30px;
  height: 30px;
  border-radius: 3px;
  object-fit: cover;
}

.brand span {
  font-family: var(--mono);
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.nav { display: flex; align-items: center; gap: 1.75rem; }

.nav a {
  font-size: 0.9375rem;
  color: var(--ink-2);
  border-bottom: 1px solid transparent;
  padding-bottom: 2px;
  transition: color 0.18s ease, border-color 0.18s ease;
}

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

.nav .btn { padding: 0.55rem 1.05rem; font-size: 0.875rem; }
.nav .btn:hover { border-bottom-color: transparent; color: var(--paper); }

.nav-toggle {
  display: none;
  width: 40px;
  height: 40px;
  padding: 0;
  border: 1px solid var(--rule);
  border-radius: 2px;
  background: transparent;
  cursor: pointer;
  position: relative;
}

.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  content: "";
  position: absolute;
  left: 11px;
  width: 16px;
  height: 1.5px;
  background: var(--ink);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle span { top: 19px; }
.nav-toggle span::before { left: 0; top: -5px; }
.nav-toggle span::after { left: 0; top: 5px; }

.nav-toggle[aria-expanded="true"] span { background: transparent; }
.nav-toggle[aria-expanded="true"] span::before { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span::after { transform: translateY(-5px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero { padding-block: clamp(4rem, 10vw, 8rem) var(--section); }

.hero .label { display: block; margin-bottom: 1.75rem; }
.hero .display { margin-bottom: 1.75rem; }
.hero .lede { margin-bottom: 2.5rem; }

.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 1.5rem; }

/* Manifest — the deliverables list, set like a table of contents */
.manifest {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--rule);
  border-left: 1px solid var(--rule);
}

.manifest li {
  border-right: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: 1.75rem 1.5rem;
}

.manifest .num {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--ink-3);
  display: block;
  margin-bottom: 0.9rem;
}

.manifest h3 { margin-bottom: 0.35rem; }
.manifest p { font-size: 0.9375rem; color: var(--ink-2); line-height: 1.55; }

/* ---------- Packages ---------- */
.packages {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
}

.package {
  display: flex;
  flex-direction: column;
  background: var(--paper);
  padding: 2.25rem 1.75rem;
}

.package--featured { background: var(--accent-soft); }

.package-head { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; margin-bottom: 1.25rem; }

.package-tag {
  font-family: var(--mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  white-space: nowrap;
}

.package h3 { margin-bottom: 0.4rem; }
.package .package-sub { font-size: 0.9375rem; color: var(--ink-2); margin-bottom: 1.75rem; }

.price {
  font-size: 2.25rem;
  line-height: 1;
  letter-spacing: -0.04em;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}

.price--request { font-size: 1.5rem; letter-spacing: -0.025em; }

.price-note {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  color: var(--ink-3);
  margin-top: 0.6rem;
  display: block;
}

.package .rule { margin-block: 1.75rem; }

.includes { margin-bottom: 2rem; }

.includes li {
  position: relative;
  padding-left: 1.5rem;
  font-size: 0.9375rem;
  line-height: 1.5;
  color: var(--ink-2);
}

.includes li + li { margin-top: 0.75rem; }

.includes li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 8px;
  height: 8px;
  border: 1px solid var(--accent);
  border-radius: 1px;
}

.package .btn { margin-top: auto; justify-content: center; }

/* ---------- Support grid ---------- */
.support {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2.5rem 2rem;
}

.support-group h3 {
  padding-bottom: 0.75rem;
  margin-bottom: 1.1rem;
  border-bottom: 1px solid var(--rule);
}

.support-group li {
  font-size: 0.9375rem;
  line-height: 1.5;
  color: var(--ink-2);
}

.support-group li + li { margin-top: 0.65rem; }

/* ---------- Catalogue (bibliography style) ---------- */
.catalogue + .catalogue { margin-top: 3.5rem; }

.catalogue > h3 {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--ink);
  margin-bottom: 0.5rem;
}

.index-list { columns: 2; column-gap: 3rem; }

.index-list li {
  display: flex;
  gap: 1rem;
  padding-block: 0.85rem;
  border-bottom: 1px solid var(--rule);
  break-inside: avoid;
  font-size: 0.9375rem;
  line-height: 1.45;
}

.index-list .num {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--ink-3);
  padding-top: 0.2em;
  flex: none;
}

/* ---------- Callout band ---------- */
.band {
  background: var(--ink);
  color: var(--paper);
  padding-block: clamp(3.5rem, 7vw, 5.5rem);
}

.band .label { color: rgba(255, 255, 255, 0.55); }
.band .h2 { margin-block: 1.5rem 1rem; }
.band p { color: rgba(255, 255, 255, 0.68); max-width: 48ch; margin-bottom: 2.25rem; }

/* ---------- Course teaser ---------- */
.teaser {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: end;
  border-top: 1px solid var(--ink);
  padding-top: 2rem;
}

.teaser .h2 { max-width: 14ch; }

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 4rem;
  align-items: start;
}

.detail-list li { padding-block: 1.1rem; border-bottom: 1px solid var(--rule); }
.detail-list li:first-child { border-top: 1px solid var(--rule); }
.detail-list .label { display: block; margin-bottom: 0.3rem; }

.detail-list a {
  font-size: 1.0625rem;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 1px;
  transition: border-color 0.18s ease, color 0.18s ease;
}

.detail-list a:hover { color: var(--accent); border-bottom-color: var(--accent); }

.form-panel { border: 1px solid var(--rule); padding: 0.5rem; }
.form-panel iframe { width: 100%; height: 640px; border: 0; display: block; }

/* ---------- Article (ML page) ---------- */
.article { max-width: 68ch; }

.article .display { max-width: 20ch; margin-bottom: 1.5rem; }

.article h2 {
  font-size: 1.375rem;
  letter-spacing: -0.02em;
  font-weight: 500;
  margin-top: 3.5rem;
  margin-bottom: 1rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--rule);
}

.article p { color: var(--ink-2); margin-bottom: 1.15rem; }
.article p:last-child { margin-bottom: 0; }

.article strong { color: var(--ink); font-weight: 600; }

.terms li { padding-block: 1.35rem; border-bottom: 1px solid var(--rule); }
.terms li:first-child { border-top: 1px solid var(--rule); }
.terms h3 { margin-bottom: 0.4rem; }
.terms p { margin-bottom: 0; font-size: 0.9375rem; }

.data-table { width: 100%; border-collapse: collapse; margin-block: 1.5rem; }

.data-table th,
.data-table td {
  text-align: left;
  padding: 0.7rem 1rem 0.7rem 0;
  border-bottom: 1px solid var(--rule);
  font-size: 0.875rem;
  font-variant-numeric: tabular-nums;
}

.data-table th {
  font-family: var(--mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-3);
  border-bottom-color: var(--ink);
}

.data-table td { color: var(--ink-2); }

.pull {
  border-left: 2px solid var(--accent);
  padding: 0.25rem 0 0.25rem 1.25rem;
  margin-top: 3rem;
  color: var(--ink);
  font-size: 1.0625rem;
}

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--rule); padding-block: 3.5rem 2.5rem; }

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2.5rem;
  margin-bottom: 3rem;
}

.footer-grid h4 { margin-bottom: 1.1rem; }

.footer-links li + li { margin-top: 0.6rem; }

.footer-links a {
  font-size: 0.9375rem;
  color: var(--ink-2);
  border-bottom: 1px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.footer-links a:hover { color: var(--ink); border-bottom-color: var(--ink); }

.footer-note {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--rule);
}

/* ---------- Reveal (progressive enhancement) ---------- */
.js .reveal { opacity: 0; transform: translateY(10px); }

.js .reveal.is-visible {
  opacity: 1;
  transform: none;
  transition: opacity 0.6s ease, transform 0.6s ease;
}

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  :root { --section: 4rem; }

  .manifest { grid-template-columns: repeat(2, 1fr); }
  .packages { grid-template-columns: 1fr; }
  .support { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; gap: 3rem; }
  .teaser { grid-template-columns: 1fr; gap: 1.5rem; align-items: start; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .index-list { columns: 1; }
}

@media (max-width: 640px) {
  .nav-toggle { display: block; }

  .nav {
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.5rem var(--gutter) 1.5rem;
    background: var(--paper);
    border-bottom: 1px solid var(--rule);
    display: none;
  }

  .nav.is-open { display: flex; }

  .nav a {
    padding-block: 0.9rem;
    border-bottom: 1px solid var(--rule);
    font-size: 1rem;
    color: var(--ink);
  }

  .nav .btn { margin-top: 1rem; justify-content: center; border-bottom: 0; }

  .manifest { grid-template-columns: 1fr; }
  .support { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 2rem; }
  .package { padding: 1.75rem 1.25rem; }
  .form-panel iframe { height: 560px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }

  .js .reveal { opacity: 1; transform: none; }
}