/* TechDocsFactory — drawing-sheet design system */

:root {
  /* light: paper, graphite line, one blue action arrow, one amber highlight */
  --paper:      #F1F4F6;
  --panel:      #FFFFFF;
  --panel-2:    #E8EDF0;
  --ink:        #12171C;
  --graphite:   #5C6975;
  --rule:       #D0D8DE;
  --rule-soft:  #E1E7EB;
  --arrow:      #1B4FD8;
  --arrow-soft: #E4EAFA;
  --highlight:  #C87F10;
  --hl-fill:    #F6E4C4;
  --shadow:     0 1px 2px rgba(18,23,28,.05), 0 12px 32px -18px rgba(18,23,28,.35);

  --f-display: "Archivo", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --f-body:    "IBM Plex Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --f-mono:    "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --gut: clamp(18px, 4vw, 44px);
  --maxw: 1180px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper:      #0D1216;
    --panel:      #141B21;
    --panel-2:    #1B242B;
    --ink:        #E8EDF1;
    --graphite:   #94A2AE;
    --rule:       #26313A;
    --rule-soft:  #1E272E;
    --arrow:      #7DA2FF;
    --arrow-soft: #17233F;
    --highlight:  #E9AE4E;
    --hl-fill:    #3A2E19;
    --shadow:     0 1px 2px rgba(0,0,0,.4), 0 14px 34px -18px rgba(0,0,0,.8);
  }
}
:root[data-theme="dark"] {
  --paper:      #0D1216;
  --panel:      #141B21;
  --panel-2:    #1B242B;
  --ink:        #E8EDF1;
  --graphite:   #94A2AE;
  --rule:       #26313A;
  --rule-soft:  #1E272E;
  --arrow:      #7DA2FF;
  --arrow-soft: #17233F;
  --highlight:  #E9AE4E;
  --hl-fill:    #3A2E19;
  --shadow:     0 1px 2px rgba(0,0,0,.4), 0 14px 34px -18px rgba(0,0,0,.8);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--f-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }

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

/* ---------- drawing-sheet primitives ---------- */

.sheet {
  max-width: var(--maxw);
  margin: 0 auto;
  padding-inline: var(--gut);
}

.band { border-top: 1px solid var(--rule); }

.band-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(48px, 7vw, 92px) var(--gut);
}

/* annotation gutter: mono label at left, content at right */
.annot {
  display: grid;
  grid-template-columns: 148px minmax(0, 1fr);
  gap: clamp(20px, 4vw, 52px);
  align-items: start;
}
@media (max-width: 860px) {
  .annot { grid-template-columns: minmax(0, 1fr); gap: 20px; }
}

.tag {
  font-family: var(--f-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .13em;
  text-transform: uppercase;
  color: var(--graphite);
  margin: 0;
  padding-top: .55em;
  border-top: 1px solid var(--ink);
  display: block;
}

h1, h2, h3 {
  font-family: var(--f-display);
  font-weight: 700;
  letter-spacing: -.028em;
  text-wrap: balance;
  margin: 0;
  line-height: 1.08;
}

h2 { font-size: clamp(27px, 3.6vw, 42px); }
h3 { font-size: 19px; letter-spacing: -.015em; line-height: 1.25; }

.lede {
  font-size: clamp(17px, 1.6vw, 19px);
  color: var(--graphite);
  max-width: 70ch;
  margin: 18px 0 0;
}
p { margin: 0; }
.stack { display: flex; flex-direction: column; gap: 18px; }

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--f-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .1em;
  text-transform: uppercase;
  text-decoration: none;
  padding: 13px 20px;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  transition: background .15s ease, color .15s ease, border-color .15s ease;
}
.btn:hover { background: var(--arrow); border-color: var(--arrow); color: #fff; }

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

/* ---------- masthead ---------- */

.masthead {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--rule);
}
.masthead-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--gut);
  height: 62px;
  display: flex;
  align-items: center;
  gap: 28px;
}
.wordmark {
  font-family: var(--f-display);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -.03em;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 9px;
  margin-right: auto;
}
.mark { width: 17px; height: 17px; flex: none; }
.navlinks { display: flex; gap: 24px; }
.navlinks a {
  font-family: var(--f-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--graphite);
  text-decoration: none;
}
.navlinks a:hover { color: var(--ink); }
.masthead .btn { padding: 9px 15px; font-size: 11px; }
@media (max-width: 800px) { .navlinks { display: none; } }

/* ---------- hero ---------- */

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, 1fr);
  gap: clamp(28px, 5vw, 64px);
  align-items: center;
  padding: clamp(46px, 6vw, 80px) 0 clamp(40px, 5vw, 68px);
}
@media (max-width: 900px) { .hero { grid-template-columns: minmax(0, 1fr); } }

.hero h1 {
  font-size: clamp(38px, 5.6vw, 66px);
  line-height: 1.02;
  letter-spacing: -.035em;
  margin-top: 22px;
}
.hero h1 em { font-style: normal; color: var(--arrow); }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.hero-meta {
  margin-top: 34px;
  padding-top: 14px;
  border-top: 1px solid var(--rule);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: .09em;
  text-transform: uppercase;
  color: var(--graphite);
}

/* image plate with SVG leader-line callouts */
.plate {
  position: relative;
  background: var(--panel);
  border: 1px solid var(--rule);
  box-shadow: var(--shadow);
}
.plate img { width: 100%; }
.plate-corner {
  position: absolute;
  inset: 7px;
  pointer-events: none;
  border: 1px solid var(--rule-soft);
}
.callouts {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  overflow: visible;
}
.callouts line, .callouts circle, .callouts path { vector-effect: non-scaling-stroke; }
.callout-text {
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
  fill: var(--ink);
}
.plate-cap {
  border-top: 1px solid var(--rule);
  padding: 10px 14px;
  display: flex;
  justify-content: space-between;
  gap: 14px;
  font-family: var(--f-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--graphite);
  background: var(--panel);
}
/* the flat-shaded CAD render is drawn on white; keep it readable in dark mode */
.plate-render { background: #fff; }

/* ---------- problem ---------- */

.problems {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
  margin-top: 34px;
}
@media (max-width: 760px) { .problems { grid-template-columns: minmax(0, 1fr); } }
.problem {
  background: var(--panel);
  padding: 26px 24px 30px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.problem .tag { border-top: none; padding-top: 0; color: var(--highlight); }
.problem p { font-size: 15.5px; }

/* ---------- thesis ---------- */

.thesis { background: var(--panel-2); }
.thesis blockquote {
  margin: 0;
  font-family: var(--f-display);
  font-weight: 600;
  font-size: clamp(24px, 3.1vw, 36px);
  line-height: 1.16;
  letter-spacing: -.028em;
  max-width: 24ch;
  text-wrap: balance;
}
.thesis .lede { margin-top: 20px; max-width: 46ch; }
.thesis-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
  gap: clamp(24px, 5vw, 60px);
  align-items: end;
}
@media (max-width: 860px) { .thesis-grid { grid-template-columns: minmax(0, 1fr); align-items: start; } }

/* ---------- flow: one source, three outputs ---------- */

.flow {
  display: grid;
  grid-template-columns: 230px 34px minmax(0, 1fr);
  gap: 0 clamp(14px, 2vw, 26px);
  align-items: center;
  margin-top: 40px;
}
@media (max-width: 900px) {
  .flow { grid-template-columns: minmax(0, 1fr); gap: 18px; }
  .flow-join { display: none; }
}
.source {
  border: 1px solid var(--rule);
  background: var(--panel);
  padding: 20px;
}
.source ul {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 9px;
  font-size: 14.5px;
}
.source li { display: flex; gap: 9px; align-items: baseline; }
.source li::before {
  content: "";
  width: 6px; height: 6px;
  flex: none;
  background: var(--arrow);
  transform: translateY(-1px);
}
.flow-join { width: 100%; height: 120px; color: var(--rule); }
.outputs {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}
@media (max-width: 760px) { .outputs { grid-template-columns: minmax(0, 1fr); } }
.output {
  background: var(--panel);
  border: 1px solid var(--rule);
  border-top: 3px solid var(--arrow);
  padding: 20px 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  text-decoration: none;
  transition: border-color .15s ease, transform .15s ease;
}
.output:hover { border-color: var(--arrow); transform: translateY(-2px); }
.output p { font-size: 14.5px; color: var(--graphite); }
.output .go {
  margin-top: auto;
  padding-top: 14px;
  font-family: var(--f-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--arrow);
}

/* ---------- feature sections ---------- */

.feature {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.08fr);
  gap: clamp(28px, 5vw, 64px);
  align-items: center;
}
@media (max-width: 900px) { .feature { grid-template-columns: minmax(0, 1fr); } }
.feature-flip .feature-media { order: -1; }
@media (max-width: 900px) { .feature-flip .feature-media { order: 0; } }
.feature h2 { margin-top: 16px; }
.ticks {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
}
.ticks li {
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  gap: 10px;
  padding: 13px 0;
  border-top: 1px solid var(--rule-soft);
  font-size: 15.5px;
}
.ticks li:last-child { border-bottom: 1px solid var(--rule-soft); }
.ticks .n {
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: .05em;
  color: var(--arrow);
  padding-top: .35em;
}

/* step sheet pair */
.sheets {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  align-items: start;
}
@media (max-width: 520px) { .sheets { grid-template-columns: minmax(0, 1fr); } }
.sheets .plate img { background: #fff; }

/* ---------- pipeline ---------- */

.pipeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
  margin-top: 36px;
}
@media (max-width: 880px) { .pipeline { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 520px) { .pipeline { grid-template-columns: minmax(0, 1fr); } }
.stage {
  background: var(--panel);
  padding: 24px 22px 28px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.stage .num {
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--arrow);
}
.stage p { font-size: 14.5px; color: var(--graphite); }

/* ---------- review ---------- */

.review {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  margin-top: 36px;
  border: 1px solid var(--rule);
}
@media (max-width: 760px) { .review { grid-template-columns: minmax(0, 1fr); } }
.review-col { padding: 26px 24px 30px; display: flex; flex-direction: column; gap: 12px; background: var(--panel); }
.review-col + .review-col { border-left: 1px solid var(--rule); background: var(--hl-fill); }
@media (max-width: 760px) { .review-col + .review-col { border-left: none; border-top: 1px solid var(--rule); } }
.review-col + .review-col .tag { color: var(--highlight); border-top-color: var(--highlight); }
.stamp {
  margin-top: 8px;
  align-self: flex-start;
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--highlight);
  border: 1px solid var(--highlight);
  padding: 6px 10px;
}

/* ---------- comparison table ---------- */

.table-wrap { overflow-x: auto; margin-top: 36px; border: 1px solid var(--rule); }
table { border-collapse: collapse; width: 100%; min-width: 620px; background: var(--panel); }
thead th {
  text-align: left;
  font-family: var(--f-mono);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--graphite);
  padding: 14px 18px;
  border-bottom: 1px solid var(--ink);
  white-space: nowrap;
}
thead th.col-new { color: var(--arrow); }
tbody th {
  text-align: left;
  font-weight: 500;
  font-size: 15px;
  padding: 16px 18px;
  width: 26%;
  border-bottom: 1px solid var(--rule-soft);
  vertical-align: top;
}
tbody td {
  font-size: 15px;
  padding: 16px 18px;
  border-bottom: 1px solid var(--rule-soft);
  vertical-align: top;
  color: var(--graphite);
}
tbody td.col-new { color: var(--ink); background: var(--arrow-soft); }
tbody tr:last-child th, tbody tr:last-child td { border-bottom: none; }

/* ---------- deployment ---------- */

.deploys { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; margin-top: 36px; }
@media (max-width: 760px) { .deploys { grid-template-columns: minmax(0, 1fr); } }
.deploy {
  border: 1px solid var(--rule);
  background: var(--panel);
  padding: 24px 22px 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.deploy .tag { border-top: none; padding-top: 0; color: var(--arrow); }
.deploy p { font-size: 15px; color: var(--graphite); }
.deploy dl {
  margin: 8px 0 0;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 8px 16px;
  font-size: 13.5px;
  border-top: 1px solid var(--rule-soft);
  padding-top: 14px;
}
.deploy dt { font-family: var(--f-mono); font-size: 10.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--graphite); padding-top: 2px; }
.deploy dd { margin: 0; }

/* ---------- cta ---------- */

.cta { background: var(--ink); color: var(--paper); border-top: 1px solid var(--ink); }
.cta h2 { color: var(--paper); font-size: clamp(28px, 4vw, 46px); max-width: 18ch; }
.cta p { color: color-mix(in srgb, var(--paper) 70%, var(--ink)); max-width: 52ch; margin-top: 18px; font-size: 17px; }
.cta .tag { color: color-mix(in srgb, var(--paper) 62%, var(--ink)); border-top-color: color-mix(in srgb, var(--paper) 45%, var(--ink)); }
.cta .btn { background: var(--paper); border-color: var(--paper); color: var(--ink); }
.cta .btn:hover { background: var(--arrow); border-color: var(--arrow); color: #fff; }
.cta-actions { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; margin-top: 28px; }
.cta-mail {
  font-family: var(--f-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: color-mix(in srgb, var(--paper) 72%, var(--ink));
  text-decoration: none;
  border-bottom: 1px solid color-mix(in srgb, var(--paper) 40%, var(--ink));
  padding-bottom: 3px;
}
.cta-mail:hover { color: var(--paper); }

/* ---------- footer title block ---------- */

footer { background: var(--paper); border-top: 1px solid var(--rule); }
.titleblock {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--gut);
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-left: 1px solid var(--rule);
  border-right: 1px solid var(--rule);
}
@media (max-width: 760px) { .titleblock { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.tb-cell { padding: 16px 18px; border-right: 1px solid var(--rule); }
.tb-cell:last-child { border-right: none; }
.tb-cell .k {
  font-family: var(--f-mono);
  font-size: 9.5px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--graphite);
  display: block;
  margin-bottom: 5px;
}
.tb-cell .v { font-size: 14px; font-weight: 500; }
.colophon {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 18px var(--gut) 40px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  align-items: center;
  font-family: var(--f-mono);
  font-size: 10.5px;
  letter-spacing: .09em;
  text-transform: uppercase;
  color: var(--graphite);
}
.colophon a { text-decoration: none; }
.colophon a:hover { color: var(--ink); }
.colophon .spacer { margin-left: auto; }

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}

/* ---------- image framing corrections ---------- */

/* the hero render is a tall portrait; crop it to a landscape plate */
.plate-render img {
  max-height: min(56vh, 520px);
  object-fit: cover;
  object-position: 50% 44%;
}

/* a generated step page is a printed sheet — keep it page-proportioned */
.sheets { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; align-items: start; }
.plate-page { margin: 0; width: 100%; }
.plate-page img { background: #fff; }
@media (max-width: 560px) { .sheets { grid-template-columns: minmax(0, 1fr); justify-items: center; } .plate-page { max-width: 340px; } }

/* the exploded line drawing sits on white paper in both themes */
.twin-view { position: relative; background: #fff; }
.twin-view img { width: 100%; height: auto; }

/* the booklet spread needs more room than the text beside it */
.feature-flip { grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); }
@media (max-width: 900px) { .feature-flip { grid-template-columns: minmax(0, 1fr); } }

/* callout chip on the 3D viewport — reads over shaded geometry */
.callout-chip {
  position: absolute;
  left: 3%;
  top: 62%;
  font-family: var(--f-mono);
  font-size: 10px;
  letter-spacing: .11em;
  text-transform: uppercase;
  color: var(--ink);
  background: var(--panel);
  border: 1px solid var(--ink);
  padding: 4px 7px;
  white-space: nowrap;
}

/* handheld screenshot — its own ground, so the shot's chrome doesn't float */
.plate-screen { margin: 0; }
.plate-screen img { background: #dfe3e6; }