/* =========================================================================
   AI Takeoff Tools, industrial design system
   ========================================================================= */

:root {
  --ink: #14110f;
  --ink-2: #2a2622;
  --ink-3: #5b554f;
  --ink-4: #8a8278;
  --rule: #1c1815;
  --paper: #f4f0e8;
  --paper-2: #ece7dc;
  --paper-3: #e2dccd;
  --accent: #b3411c;
  --accent-ink: #5a1f0c;
  --grid: rgba(20, 17, 15, 0.06);
  --grid-strong: rgba(20, 17, 15, 0.12);

  --serif: "IBM Plex Serif", "Source Serif Pro", Georgia, "Times New Roman", serif;
  --sans: "Inter", "IBM Plex Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --measure: 68ch;
  --gutter: clamp(1rem, 2.4vw, 2rem);
  --col: clamp(0.875rem, 1.2vw, 1rem);
}

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

html {
  font-size: 17px;
  -webkit-text-size-adjust: 100%;
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  background-color: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  line-height: 1.55;
  font-feature-settings: "kern", "liga", "calt";
  background-image:
    linear-gradient(to right, var(--grid) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid) 1px, transparent 1px);
  background-size: 64px 64px;
  background-position: -1px -1px;
}

::selection { background: var(--ink); color: var(--paper); }

a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
  text-decoration-color: var(--ink-4);
  transition: text-decoration-color 120ms ease, color 120ms ease;
}
a:hover { text-decoration-color: var(--ink); }

h1, h2, h3, h4, h5 {
  font-family: var(--serif);
  font-weight: 500;
  letter-spacing: -0.012em;
  line-height: 1.12;
  margin: 0;
  color: var(--ink);
}

h1 { font-size: clamp(2.5rem, 5.6vw, 4.4rem); letter-spacing: -0.022em; }
h2 { font-size: clamp(1.75rem, 3.1vw, 2.4rem); letter-spacing: -0.018em; }
h3 { font-size: clamp(1.25rem, 2vw, 1.55rem); }
h4 { font-size: 1.05rem; font-family: var(--mono); letter-spacing: 0.04em; text-transform: uppercase; }

p { margin: 0 0 1em; max-width: var(--measure); }

small, .small { font-size: 0.8rem; color: var(--ink-3); }

code, kbd, samp, pre { font-family: var(--mono); font-size: 0.92em; }

hr {
  border: 0;
  border-top: 1px solid var(--rule);
  margin: 3rem 0;
}

/* ---------- Layout shell ---------- */

.shell {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.shell--narrow {
  max-width: 960px;
}

.shell--wide {
  max-width: 1440px;
}

/* ---------- Site header ---------- */

.site-header {
  border-bottom: 1px solid var(--rule);
  background: var(--paper);
  position: sticky;
  top: 0;
  z-index: 50;
  background-image:
    linear-gradient(to right, var(--grid) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid) 1px, transparent 1px);
  background-size: 64px 64px;
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
  gap: 1.5rem;
}

.brand {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--ink);
  display: inline-flex;
  align-items: baseline;
  gap: 0.6rem;
}

.brand__mark {
  display: inline-block;
  width: 11px;
  height: 11px;
  background: var(--ink);
  position: relative;
  top: 0;
  flex: none;
}

.brand__sep {
  color: var(--ink-4);
  font-weight: 400;
}

.site-nav {
  display: flex;
  gap: 1.5rem;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.site-nav a {
  color: var(--ink-2);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  padding-bottom: 0.18rem;
}

.site-nav a:hover {
  border-bottom-color: var(--ink);
  color: var(--ink);
}

@media (max-width: 720px) {
  .site-nav { display: none; }
}

/* ---------- Section heading: numbered industrial style ---------- */

.section-marker {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin: 0 0 1.25rem;
}

.section-marker::before {
  content: "";
  width: 1.5rem;
  height: 1px;
  background: var(--ink-3);
  display: inline-block;
}

.section-number {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
}

/* ---------- Hero ---------- */

.hero {
  padding: clamp(3rem, 8vw, 7rem) 0 clamp(2.5rem, 5vw, 4rem);
  border-bottom: 1px solid var(--rule);
  position: relative;
}

.hero__eyebrow {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.hero__eyebrow::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--ink-3);
  max-width: 8rem;
}

.hero__title {
  max-width: 16ch;
  margin-bottom: 1.25rem;
}

.hero__lede {
  font-family: var(--serif);
  font-size: clamp(1.15rem, 1.7vw, 1.4rem);
  line-height: 1.5;
  color: var(--ink-2);
  max-width: 56ch;
  margin: 0 0 2rem;
}

.hero__meta {
  display: flex;
  gap: 2.5rem;
  flex-wrap: wrap;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--ink-3);
}

.hero__meta dt {
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.68rem;
  margin-bottom: 0.2rem;
}

.hero__meta dd {
  margin: 0;
  color: var(--ink);
}

/* ---------- Bar chart (industrial) ---------- */

.bars {
  display: flex;
  flex-direction: column;
  gap: 1.4rem;
  margin: 1.5rem 0 1.5rem;
  font-family: var(--mono);
  font-size: 0.82rem;
  width: 100%;
  max-width: 620px;
}

.bars__group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.bars__axis {
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin: 0 0 0.15rem;
}

.bars__row {
  display: grid;
  grid-template-columns: 13ch 1fr 3.5ch;
  gap: 0.75rem;
  align-items: center;
}

.bars__label {
  color: var(--ink-2);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.bars__track {
  display: block;
  height: 14px;
  background: var(--paper-3);
  border: 1px solid var(--rule);
  position: relative;
  overflow: hidden;
}

.bars__fill {
  display: block;
  height: 100%;
  min-width: 2px;
  background: var(--ink);
}

.bars__fill--accent { background: var(--accent); }

.bars__value {
  color: var(--ink-2);
  text-align: right;
  font-feature-settings: "tnum";
}

.bars__row--lift .bars__fill { background: var(--accent); }
.bars__row--lift .bars__label { color: var(--ink); font-weight: 500; }

/* Legend keys (versus pages) */
.legend-key {
  display: inline-block;
  width: 0.85rem;
  height: 0.85rem;
  vertical-align: -1px;
  margin-right: 0.35rem;
  border: 1px solid var(--rule);
}
.legend-key--accent { background: var(--accent); border-color: var(--accent); }
.legend-key--ink { background: var(--ink); border-color: var(--ink); }

/* ---------- Comparison table ---------- */

.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--sans);
  font-size: 0.95rem;
  margin: 1.25rem 0 2rem;
}

.spec-table th, .spec-table td {
  text-align: left;
  vertical-align: top;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--rule);
}

.spec-table thead th {
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  border-bottom: 1px solid var(--ink);
  padding-bottom: 0.6rem;
  font-weight: 500;
}

.spec-table th:first-child, .spec-table td:first-child {
  padding-left: 0;
}
.spec-table th:last-child, .spec-table td:last-child {
  padding-right: 0;
}

.spec-table .col-attr {
  width: 26%;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.spec-table .col-lift {
  width: 37%;
}

.spec-table .col-other {
  width: 37%;
  color: var(--ink-2);
}

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

/* ---------- Pro / Con lists ---------- */

.proscons {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  margin: 1.5rem 0 2.5rem;
}

@media (max-width: 720px) {
  .proscons { grid-template-columns: 1fr; gap: 1.5rem; }
}

.proscons h4 {
  margin-bottom: 1rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--ink);
}

.proscons ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.proscons li {
  padding: 0.5rem 0 0.5rem 1.5rem;
  position: relative;
  border-bottom: 1px solid var(--rule);
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--ink-2);
}

.proscons li:last-child { border-bottom: 0; }

.proscons li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.95rem;
  width: 0.75rem;
  height: 1px;
  background: var(--ink-3);
}

.proscons--lift li::before { background: var(--accent); }

/* ---------- Index card grid (homepage list of comparisons) ---------- */

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 0;
  margin: 2rem 0 4rem;
  border-top: 1px solid var(--ink);
}

.card {
  display: block;
  text-decoration: none;
  color: inherit;
  padding: 1.5rem 1.5rem 1.75rem;
  border-bottom: 1px solid var(--rule);
  border-right: 1px solid var(--rule);
  background: var(--paper);
  position: relative;
  transition: background 120ms ease;
}

.card:hover {
  background: var(--paper-2);
}

.card__num {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 0.85rem;
  display: block;
}

.card__title {
  font-family: var(--serif);
  font-size: 1.4rem;
  line-height: 1.18;
  letter-spacing: -0.012em;
  margin-bottom: 0.6rem;
}

.card__title em {
  font-style: italic;
  color: var(--ink-3);
  font-weight: 400;
}

.card__sub {
  font-size: 0.88rem;
  color: var(--ink-3);
  line-height: 1.5;
}

.card__arrow {
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink);
  margin-top: 1rem;
  display: inline-block;
}

/* ---------- Article body ---------- */

.prose {
  font-family: var(--serif);
  font-size: 1.075rem;
  line-height: 1.65;
  color: var(--ink-2);
  max-width: var(--measure);
}

.prose p { margin: 0 0 1.15em; }
.prose strong { color: var(--ink); font-weight: 600; }
.prose a { color: var(--ink); }

/* ---------- Quote (pull) ---------- */

.pull {
  font-family: var(--serif);
  font-size: clamp(1.4rem, 2vw, 1.85rem);
  line-height: 1.3;
  color: var(--ink);
  border-left: 2px solid var(--accent);
  padding: 0.25rem 0 0.25rem 1.5rem;
  margin: 2.5rem 0;
  max-width: 50ch;
  font-style: italic;
}

.pull cite {
  display: block;
  margin-top: 0.85rem;
  font-style: normal;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
}

/* ---------- Spec sheet (mono table) ---------- */

.specsheet {
  font-family: var(--mono);
  font-size: 0.86rem;
  color: var(--ink-2);
  margin: 1.5rem 0 2rem;
  border-top: 1px solid var(--ink);
}

.specsheet__row {
  display: grid;
  grid-template-columns: 18ch 1fr;
  gap: 1.5rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--rule);
  line-height: 1.5;
}

.specsheet__key {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.74rem;
  color: var(--ink-3);
  padding-top: 0.1rem;
}

.specsheet__val { color: var(--ink); }

@media (max-width: 560px) {
  .specsheet__row { grid-template-columns: 1fr; gap: 0.3rem; }
}

/* ---------- Tag chip ---------- */

.tag {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  border: 1px solid var(--ink-3);
  padding: 0.18rem 0.55rem;
  margin: 0 0.4rem 0.4rem 0;
}

.tag--ink { color: var(--paper); background: var(--ink); border-color: var(--ink); }
.tag--accent { color: var(--paper); background: var(--accent); border-color: var(--accent); }

/* ---------- Crossref (related compare links) ---------- */

.crossref {
  border-top: 1px solid var(--ink);
  margin-top: 4rem;
  padding-top: 2rem;
}

.crossref h4 {
  margin-bottom: 1.25rem;
}

.crossref ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 0.4rem 1.5rem;
}

.crossref li {
  padding: 0.6rem 0;
  border-bottom: 1px solid var(--rule);
}

.crossref a {
  font-family: var(--serif);
  font-size: 1.05rem;
  text-decoration: none;
  color: var(--ink);
}

.crossref a:hover {
  text-decoration: underline;
  text-decoration-color: var(--ink);
}

.crossref a em {
  font-style: italic;
  color: var(--ink-3);
  font-weight: 400;
}

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--ink);
  margin-top: 6rem;
  padding: 3rem 0 4rem;
  background: var(--paper);
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink-3);
}

.site-footer__inner {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 2rem;
}

@media (max-width: 720px) {
  .site-footer__inner { grid-template-columns: 1fr; }
}

.site-footer h5 {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin: 0 0 1rem;
  font-weight: 500;
}

.site-footer ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.site-footer li { padding: 0.25rem 0; }

.site-footer a {
  color: var(--ink-2);
  text-decoration: none;
}

.site-footer a:hover { color: var(--ink); text-decoration: underline; }

.site-footer__sponsor {
  margin-top: 3rem;
  border-top: 1px solid var(--ink);
  padding-top: 1.75rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.site-footer__sponsor-text {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.site-footer__sponsor-label {
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-4);
}

.site-footer__sponsor-name {
  font-family: var(--serif);
  font-size: 1.25rem;
  letter-spacing: -0.01em;
  color: var(--ink);
  text-decoration: none;
  transition: color 120ms ease;
}

a.site-footer__sponsor-name:hover {
  color: var(--accent);
}

.site-footer__sponsor-sub {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.02em;
}

.site-footer__sponsor-link {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--ink);
  border-bottom: 1px solid var(--ink-4);
  padding-bottom: 0.2rem;
  white-space: nowrap;
  transition: border-color 120ms ease, color 120ms ease;
}

.site-footer__sponsor-link:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.site-footer__legal {
  margin-top: 2rem;
  border-top: 1px solid var(--rule);
  padding-top: 1.5rem;
  font-size: 0.72rem;
  color: var(--ink-4);
  line-height: 1.6;
  max-width: 70ch;
}

/* ---------- Verdict (final take) ---------- */

.verdict {
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
  padding: 2.5rem 0;
  margin: 4rem 0 2rem;
  position: relative;
}

.verdict__title {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1rem;
}

.verdict__body {
  font-family: var(--serif);
  font-size: clamp(1.1rem, 1.55vw, 1.3rem);
  line-height: 1.55;
  color: var(--ink);
  max-width: 60ch;
}

/* ---------- Index hero variant (homepage) ---------- */

.index-hero {
  padding: clamp(4rem, 10vw, 8rem) 0 clamp(3rem, 6vw, 5rem);
  border-bottom: 1px solid var(--ink);
}

.index-hero__layout {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 4rem;
  align-items: end;
}

@media (max-width: 880px) {
  .index-hero__layout { grid-template-columns: 1fr; gap: 2rem; }
}

.index-hero__numbers {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink-3);
  border-left: 1px solid var(--rule);
  padding-left: 1.5rem;
  display: grid;
  gap: 1.25rem;
}

.index-hero__numbers div { line-height: 1.3; }

.index-hero__numbers strong {
  display: block;
  font-family: var(--serif);
  font-size: 2rem;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: -0.01em;
  margin-bottom: 0.15rem;
}

/* ---------- Utility ---------- */

.u-mt-0 { margin-top: 0; }
.u-mt-1 { margin-top: 1rem; }
.u-mt-2 { margin-top: 2rem; }
.u-mt-4 { margin-top: 4rem; }
.u-mb-0 { margin-bottom: 0; }
.u-mb-2 { margin-bottom: 2rem; }
.u-mb-4 { margin-bottom: 4rem; }
.u-divider {
  border: 0;
  border-top: 1px solid var(--rule);
  margin: 3rem 0;
}
.u-divider--ink {
  border-top: 1px solid var(--ink);
}

/* ---------- Print ---------- */

@media print {
  body { background: white; }
  .site-header, .site-footer, .crossref { display: none; }
  a { color: black; text-decoration: none; }
}