/* Builders Club — refined identity system
   Antimetal-style restraint on the red brand board: paper ground, hairline
   rules and register marks, tiny mono labels, serif statements, red as
   accent only. Fonts: Fraunces (serif), Inter (body), IBM Plex Mono (labels). */

:root {
  --red: #b94f3d;
  --red-deep: #9e4234;
  --paper: #f4f0e8;
  --ink: #242322;
  --grey: #b7b0a7;
  --grey-dark: #6f6a61;
  --blue: #416d91;
  --line: rgba(36, 35, 34, 0.16);
  --line-strong: rgba(36, 35, 34, 0.4);
  --serif: "Fraunces", Georgia, serif;
  --body: "Inter", "Helvetica Neue", Arial, sans-serif;
  --mono: "IBM Plex Mono", "SF Mono", Menlo, monospace;
  --pad-x: 48px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--ink);
  background: var(--paper);
}

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

a { color: inherit; }

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

/* ---------- type ---------- */

.serif {
  font-family: var(--serif);
  font-weight: 500;
  line-height: 1.16;
  letter-spacing: -0.01em;
}

.serif-xl { font-size: clamp(2.3rem, 5.5vw, 3.8rem); }
.serif-lg { font-size: clamp(1.5rem, 3vw, 2.1rem); }

.mono {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.64rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.mono-red { color: var(--red); }
.mono-grey { color: var(--grey-dark); }

.lede { font-size: 1.08rem; max-width: 54ch; color: var(--ink); }

p + p { margin-top: 0.95rem; }

.meta { margin-top: 1.8rem; color: var(--grey-dark); }

.meta .sep { color: var(--grey); padding: 0 0.7em; }

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

.site-header {
  background: var(--paper);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 50;
}

.nav-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 16px var(--pad-x);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.logo { text-decoration: none; display: block; line-height: 1.4; }

.logo .logo-name {
  font-family: var(--mono);
  font-weight: 600;
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  color: var(--red);
  text-transform: uppercase;
  display: block;
}

.logo .logo-affil {
  font-family: var(--mono);
  font-weight: 400;
  font-size: 0.56rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--grey-dark);
  display: block;
  margin-top: 2px;
}

.site-nav { display: flex; gap: 30px; align-items: center; }

.site-nav a {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.62rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--grey-dark);
  padding: 6px 0;
}

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

.site-nav a[aria-current="page"] { color: var(--red); }

.burger {
  display: none;
  background: none;
  border: 1px solid var(--line-strong);
  color: var(--ink);
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.6rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 8px 13px;
  cursor: pointer;
}

/* ---------- page frame ---------- */

.frame {
  max-width: 1120px;
  margin: 0 auto;
  border-left: 1px solid var(--line);
  border-right: 1px solid var(--line);
}

.sec {
  position: relative;
  border-top: 1px solid var(--line);
  padding: 80px var(--pad-x);
}

.sec:first-child { border-top: none; }

/* register marks at rule intersections */
.sec::before,
.sec::after {
  content: "+";
  position: absolute;
  top: -10px;
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1;
  color: var(--grey);
  background: var(--paper);
  padding: 2px 1px;
}

.sec::before { left: -5px; }
.sec::after { right: -5px; }

.sec:first-child::before,
.sec:first-child::after { content: none; }

.sec-head { display: flex; align-items: baseline; gap: 14px; margin-bottom: 52px; }

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

.hero { padding-top: 104px; padding-bottom: 88px; text-align: center; }

.hero > .mono { display: block; margin-bottom: 2rem; }

.hero .serif-xl { margin-bottom: 1.5rem; }

.hero .lede { margin: 0 auto 2.6rem; }

.hero .btn-row { justify-content: center; }

.hero-media { margin: 72px calc(-1 * var(--pad-x)) 0; border-top: 1px solid var(--line); position: relative; }

.hero-media::before,
.hero-media::after {
  content: "+";
  position: absolute;
  top: -10px;
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1;
  color: var(--grey);
  background: var(--paper);
  padding: 2px 1px;
}

.hero-media::before { left: -5px; }
.hero-media::after { right: -5px; }

.hero-media figure { padding: var(--pad-x) var(--pad-x) 0; }

.hero-media img { width: 100%; aspect-ratio: 21 / 9; object-fit: cover; border: 1px solid var(--line-strong); }

.fig-row {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 12px;
  color: var(--grey-dark);
}

/* inner page heroes */
.page-hero { text-align: left; padding-top: 88px; padding-bottom: 80px; }

.page-hero .lede { margin: 0; }

.page-hero .serif-xl { margin-bottom: 1.4rem; }

.page-hero .btn-row { justify-content: flex-start; }

/* ---------- spec strip ---------- */

.spec { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line); }

.spec-cell { padding: 18px 24px 20px 28px; border-left: 1px solid var(--line); }

.spec-cell:first-child { border-left: none; padding-left: var(--pad-x); }

.spec-cell .k { display: block; color: var(--grey-dark); margin-bottom: 3px; }

.spec-cell .v { color: var(--ink); }

.dot {
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--red);
  margin-right: 7px;
  vertical-align: 1px;
}

/* ---------- buttons & links ---------- */

.btn-row { display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
  display: inline-block;
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.62rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  text-decoration: none;
  padding: 13px 22px;
  border: 1px solid var(--line-strong);
  color: var(--ink);
  background: transparent;
  transition: color 140ms ease, background 140ms ease, border-color 140ms ease;
}

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

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

.btn-red:hover { background: var(--red-deep); border-color: var(--red-deep); color: var(--paper); }

.link-rows { border-top: 1px solid var(--line); }

.link-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 18px 2px;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  color: var(--ink);
}

.link-row:hover { color: var(--red); }

.link-row .note { color: var(--grey-dark); }

/* ---------- splits ---------- */

.split { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }

.split + .split { margin-top: 96px; }

.split.flip .split-media { order: 2; }

.split-copy .serif-lg { margin-bottom: 1.2rem; }

.split-copy .mono { display: block; margin-bottom: 1.4rem; }

.split-copy p { font-size: 0.98rem; }

/* two-column editorial (statement + detail) */
.duo { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: start; }

.duo .serif-lg { max-width: 16ch; }

.duo p { font-size: 0.98rem; }

/* ---------- values ---------- */

.values { display: grid; grid-template-columns: repeat(5, 1fr); }

.value { padding: 6px 24px 0; border-left: 1px solid var(--line); }

.value:first-child { border-left: none; padding-left: 0; }

.value:last-child { padding-right: 0; }

.value .value-num { display: block; margin-bottom: 1.6rem; }

.value .value-icon { width: 22px; height: 22px; margin-bottom: 1rem; }

.value h3 {
  font-family: var(--mono);
  font-weight: 600;
  font-size: 0.64rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink);
  margin-bottom: 0.7rem;
}

.value p { font-size: 0.84rem; color: var(--grey-dark); line-height: 1.65; }

/* ---------- cells (steps / phases) ---------- */

.cells { display: grid; grid-template-columns: repeat(3, 1fr); }

.cell { padding: 6px 28px 0; border-left: 1px solid var(--line); }

.cell:first-child { border-left: none; padding-left: 0; }

.cell:last-child { padding-right: 0; }

.cell .cell-num { display: block; margin-bottom: 1.4rem; }

.cell h3 {
  font-family: var(--mono);
  font-weight: 600;
  font-size: 0.66rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink);
  margin-bottom: 0.3rem;
}

.cell .cell-sub { display: block; color: var(--grey-dark); margin-bottom: 1.1rem; }

.cell p { font-size: 0.92rem; color: var(--ink); }

/* ---------- build card ---------- */

.build-card { border: 1px solid var(--line-strong); display: grid; grid-template-columns: 1.1fr 0.9fr; }

.build-card-main { padding: 44px; border-right: 1px solid var(--line); }

.build-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2rem, 4.5vw, 3rem);
  line-height: 1.1;
  color: var(--ink);
}

.build-title .num { color: var(--red); }

.build-tag { margin-top: 1.2rem; font-size: 1rem; color: var(--grey-dark); }

.build-card-main .meta { margin-top: 2.4rem; }

.build-card-meta { padding: 44px; display: flex; flex-direction: column; gap: 20px; justify-content: center; }

.build-meta-row { border-top: 1px solid var(--line); padding-top: 12px; }

.build-meta-row:first-child { border-top: none; padding-top: 0; }

.build-meta-row .k { display: block; color: var(--grey-dark); margin-bottom: 3px; }

.build-meta-row .v { font-size: 0.94rem; }

/* ---------- photos ---------- */

figure.photo { margin: 0; }

figure.photo img { width: 100%; border: 1px solid var(--line-strong); }

figure.photo figcaption {
  margin-top: 11px;
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.56rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--grey-dark);
}

figure.photo figcaption .fig-num { color: var(--red); margin-right: 0.9em; }

.photo-strip, .photo-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; align-items: start; }

.photo-strip figure.photo img, .photo-grid figure.photo img { aspect-ratio: 4 / 3; object-fit: cover; }

.split-media figure.photo img { aspect-ratio: 4 / 3.3; object-fit: cover; }

/* ---------- CTA ---------- */

.cta { text-align: center; padding-top: 96px; padding-bottom: 104px; overflow: hidden; }

.cta .serif-lg { margin-bottom: 1rem; }

.cta .lede { margin: 0 auto 2.4rem; color: var(--grey-dark); }

.cta .btn-row { justify-content: center; }

.cta-dots {
  position: absolute;
  right: -60px;
  bottom: -60px;
  width: 300px;
  height: 300px;
  color: var(--red);
  opacity: 0.3;
  pointer-events: none;
  background-image: radial-gradient(currentColor 1px, transparent 1px);
  background-size: 8px 8px;
  -webkit-mask-image: radial-gradient(circle at 100% 100%, #000 30%, transparent 72%);
  mask-image: radial-gradient(circle at 100% 100%, #000 30%, transparent 72%);
}

/* ---------- footer ---------- */

.site-footer { border-top: 1px solid var(--line); }

.footer-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 60px var(--pad-x) 40px;
  border-left: 1px solid var(--line);
  border-right: 1px solid var(--line);
}

.footer-grid { display: flex; justify-content: space-between; align-items: flex-start; gap: 40px; flex-wrap: wrap; }

.footer-note { margin-top: 16px; font-size: 0.88rem; color: var(--grey-dark); max-width: 38ch; }

.footer-links { display: flex; flex-direction: column; gap: 12px; }

.footer-links a {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.6rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--grey-dark);
  text-decoration: none;
}

.footer-links a:hover { color: var(--red); }

.footer-seal { width: 96px; height: 96px; opacity: 0.9; }

.footer-fine {
  margin-top: 52px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  color: var(--grey-dark);
}

/* ---------- responsive ---------- */

@media (max-width: 920px) {
  :root { --pad-x: 24px; }
  .split, .duo { grid-template-columns: 1fr; gap: 36px; }
  .split.flip .split-media { order: 0; }
  .split + .split { margin-top: 64px; }
  .values { grid-template-columns: 1fr; }
  .value { border-left: none; border-top: 1px solid var(--line); padding: 20px 0 14px; }
  .value:first-child { border-top: none; padding-top: 0; }
  .value .value-num { margin-bottom: 0.8rem; }
  .cells { grid-template-columns: 1fr; }
  .cell { border-left: none; border-top: 1px solid var(--line); padding: 22px 0 8px; }
  .cell:first-child { border-top: none; padding-top: 0; }
  .spec { grid-template-columns: 1fr 1fr; }
  .spec-cell { padding: 14px 20px 16px var(--pad-x); }
  .spec-cell:nth-child(3) { border-left: none; }
  .spec-cell:nth-child(n+3) { border-top: 1px solid var(--line); }
  .photo-strip, .photo-grid { grid-template-columns: 1fr; }
  .build-card { grid-template-columns: 1fr; }
  .build-card-main { border-right: none; border-bottom: 1px solid var(--line); padding: 28px; }
  .build-card-meta { padding: 28px; }
  .sec { padding-top: 56px; padding-bottom: 56px; }
  .hero { padding-top: 72px; }
  .hero-media figure { padding: 24px 24px 0; }
}

@media (max-width: 720px) {
  .burger { display: block; }
  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--paper);
    flex-direction: column;
    align-items: flex-start;
    padding: 14px 24px 24px;
    gap: 18px;
    border-bottom: 1px solid var(--line-strong);
  }
  .site-nav.open { display: flex; }
}