/* ==========================================================================
   IRONSTONE — Construction Materials
   Design tokens
   ========================================================================== */
:root {
  --bg-primary:          #0A0A0C;
  --bg-elevated:          #16171A;
  --bg-elevated-alt:      #1D1E22;

  --text-heading:         #F2F2F0;
  --text-body:            #9AA1A8;
  --text-muted:           #6E7278;

  --accent-gold:          #C98A4B;
  --accent-gold-bright:   #E0A868;

  --border-hairline:      #232427;
  --border-hairline-alt:  rgba(255, 255, 255, 0.08);

  --font-heading: 'Oswald', sans-serif;
  --font-body: 'Inter', sans-serif;

  --header-h: 92px;
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ==========================================================================
   Reset & base
   ========================================================================== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg-primary);
  color: var(--text-body);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
ul, ol { margin: 0; padding: 0; }
a { color: inherit; }
button { font-family: inherit; }
h1, h2, h3 { margin: 0; font-weight: 600; }

body.no-scroll { overflow: hidden; }

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 32px;
}

.eyebrow {
  font-family: var(--font-heading);
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.78rem;
  color: var(--accent-gold);
  font-weight: 500;
  margin: 0 0 10px;
}

.section-head {
  max-width: 640px;
  margin: 0 auto 56px;
  text-align: center;
}
.section-head h2 { font-family: var(--font-heading); font-size: clamp(1.8rem, 3vw, 2.6rem); color: var(--text-heading); margin: 4px 0 16px; line-height: 1.2; }
.section-head__intro { color: var(--text-body); line-height: 1.7; margin: 0; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 15px 30px;
  font-family: var(--font-heading);
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-decoration: none;
  border-radius: 2px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.25s var(--ease), border-color 0.25s var(--ease), color 0.25s var(--ease), transform 0.25s var(--ease);
}
.btn--primary { background: var(--accent-gold); color: var(--bg-primary); }
.btn--primary:hover { background: var(--accent-gold-bright); transform: translateY(-2px); }
.btn--ghost { border-color: rgba(255, 255, 255, 0.35); color: var(--text-heading); }
.btn--ghost:hover { border-color: var(--accent-gold); color: var(--accent-gold); transform: translateY(-2px); }

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--accent-gold);
  color: var(--bg-primary);
  padding: 12px 20px;
  z-index: 2000;
  font-family: var(--font-heading);
  font-weight: 600;
  text-decoration: none;
}
.skip-link:focus { left: 16px; top: 16px; }

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

/* ==========================================================================
   Scroll reveal (generic)
   ========================================================================== */
/* :not(.is-visible) bumps specificity to 0-2-0 so this reliably beats a component's
   own base opacity/transform rule (e.g. .project-card) at equal 0-1-0 specificity —
   otherwise, whichever rule is later in the cascade wins outright and the card never
   actually starts hidden. */
[data-reveal]:not(.is-visible) {
  opacity: 0;
  transform: translateY(28px);
}
[data-reveal] {
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
[data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================================================
   Preloader
   ========================================================================== */
.preloader {
  position: fixed;
  inset: 0;
  z-index: 3000;
  background: var(--bg-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 0.5s var(--ease), visibility 0s linear 0.5s;
}
.preloader.is-hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}
.preloader__mark { display: flex; flex-direction: column; align-items: center; gap: 24px; }
.preloader__bar { width: 180px; height: 2px; background: rgba(255, 255, 255, 0.12); overflow: hidden; }
.preloader__bar-fill { display: block; width: 0%; height: 100%; background: var(--accent-gold); transition: width 1s var(--ease); }

/* ==========================================================================
   Logo chip
   ========================================================================== */
.logo-chip {
  display: inline-flex;
  align-items: center;
  background: #F2F1EE;
  border-radius: 8px;
  padding: 8px 14px;
  line-height: 0;
  text-decoration: none;
  transition: padding 0.3s var(--ease);
}
.logo-chip__img { display: block; height: 40px; width: auto; }
.logo-chip--preloader { padding: 10px 16px; }
.logo-chip--preloader .logo-chip__img { height: 48px; }
.logo-chip--footer .logo-chip__img { height: 48px; }

/* ==========================================================================
   Header / nav
   ========================================================================== */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 900;
  padding: 22px 0;
  border-bottom: 1px solid transparent;
  transition: padding 0.3s var(--ease), background 0.3s var(--ease), border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}
.site-header.is-scrolled {
  padding: 12px 0;
  background: rgba(10, 10, 12, 0.92);
  backdrop-filter: blur(10px);
  border-bottom-color: var(--border-hairline);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
}
.site-header.is-scrolled .logo-chip { padding: 5px 10px; }
.site-header.is-scrolled .logo-chip__img { height: 32px; }

.site-header__inner { display: flex; align-items: center; justify-content: space-between; }

.main-nav__list { display: flex; gap: 36px; list-style: none; }
.main-nav__link {
  position: relative;
  display: inline-block;
  color: var(--text-body);
  text-decoration: none;
  font-family: var(--font-heading);
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding-bottom: 6px;
  transition: color 0.25s var(--ease);
}
.main-nav__link::after {
  content: '';
  position: absolute;
  left: 0; bottom: 0;
  width: 100%; height: 1px;
  background: var(--accent-gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s var(--ease);
}
.main-nav__link:hover, .main-nav__link.is-active { color: var(--text-heading); }
.main-nav__link:hover::after, .main-nav__link.is-active::after { transform: scaleX(1); }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px; height: 40px;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: 950;
}
.nav-toggle__bar {
  display: block;
  width: 100%; height: 2px;
  background: var(--text-heading);
  transition: transform 0.3s var(--ease), opacity 0.3s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: var(--bg-primary);
}
.hero__slides { position: absolute; inset: 0; overflow: hidden; }
.hero__slide {
  position: absolute;
  inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  opacity: 0;
  filter: grayscale(100%) contrast(1.05) brightness(0.95);
  transition: opacity 1.2s var(--ease);
  animation: none;
}
.hero__slide.is-active {
  opacity: 1;
  z-index: 1;
  animation: heroKenBurns 7000ms var(--ease) forwards;
}
@keyframes heroKenBurns {
  from { transform: scale(1); }
  to   { transform: scale(1.08); }
}
.hero__overlay {
  position: absolute;
  inset: 0;
  z-index: 2;
  background: linear-gradient(to bottom, rgba(10, 10, 12, 0.45) 0%, rgba(10, 10, 12, 0.55) 45%, rgba(10, 10, 12, 0.92) 100%);
  pointer-events: none;
}
.hero__content { position: relative; z-index: 3; max-width: 760px; padding-top: var(--header-h); }
.hero__headline {
  font-family: var(--font-heading);
  font-size: clamp(2.4rem, 6vw, 4.4rem);
  line-height: 1.08;
  color: var(--text-heading);
  margin: 14px 0 24px;
}
.hero__subhead { font-size: 1.1rem; line-height: 1.7; color: var(--text-body); max-width: 600px; margin: 0 0 36px; }
.hero__ctas { display: flex; flex-wrap: wrap; gap: 18px; }

.hero__controls {
  position: absolute;
  right: 32px;
  bottom: 40px;
  z-index: 3;
  display: flex;
  align-items: center;
  gap: 16px;
}
.hero__arrow {
  width: 42px; height: 42px;
  border-radius: 50%;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.3);
  color: var(--text-heading);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  transition: border-color 0.25s var(--ease), color 0.25s var(--ease);
}
.hero__arrow:hover { border-color: var(--accent-gold); color: var(--accent-gold); }
.hero__dots { display: flex; gap: 10px; }
.hero__dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  border: none;
  padding: 0;
  cursor: pointer;
  transition: background 0.25s var(--ease), transform 0.25s var(--ease);
}
.hero__dot.is-active { background: var(--accent-gold); transform: scale(1.3); }

.hero__scroll-cue {
  position: absolute;
  left: 32px;
  bottom: 40px;
  z-index: 3;
  width: 1px; height: 56px;
  text-decoration: none;
}
.hero__scroll-cue-line { position: relative; display: block; width: 100%; height: 100%; background: rgba(255, 255, 255, 0.25); }
.hero__scroll-cue-line::after {
  content: '';
  position: absolute;
  top: 0; left: 50%;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--accent-gold);
  transform: translateX(-50%);
  animation: scrollCue 1.8s ease-in-out infinite;
}
@keyframes scrollCue {
  0% { top: 0; opacity: 0; }
  30% { opacity: 1; }
  100% { top: 100%; opacity: 0; }
}

/* ==========================================================================
   Marquee divider
   ========================================================================== */
.marquee {
  overflow: hidden;
  background: var(--bg-elevated);
  border-top: 1px solid var(--border-hairline);
  border-bottom: 1px solid var(--border-hairline);
  padding: 20px 0;
}
.marquee__track { display: flex; width: max-content; animation: marqueeScroll 32s linear infinite; }
.marquee:hover .marquee__track { animation-play-state: paused; }
.marquee__group { display: inline-flex; align-items: center; flex-wrap: nowrap; }
.marquee__item {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-body);
  padding: 0 18px;
  white-space: nowrap;
}
.marquee__sep { color: var(--accent-gold); font-size: 0.6rem; }
@keyframes marqueeScroll {
  from { transform: translateX(0); }
  to   { transform: translateX(-50%); }
}

/* ==========================================================================
   About
   ========================================================================== */
.about { padding: 130px 0; }
.about__grid { display: grid; grid-template-columns: 1.3fr 1fr; gap: 64px; align-items: start; }
.about__copy h2 { font-family: var(--font-heading); font-size: clamp(1.8rem, 3vw, 2.6rem); color: var(--text-heading); margin: 12px 0 20px; line-height: 1.25; }
.about__copy p { font-size: 1.05rem; line-height: 1.75; margin: 0; }

.about__stats { display: grid; grid-template-columns: 1fr 1fr; gap: 36px 28px; }
.stat { border-left: 2px solid var(--accent-gold); padding-left: 18px; }
.stat__number { display: block; font-family: var(--font-heading); font-size: clamp(2.2rem, 4vw, 3rem); color: var(--accent-gold); font-weight: 600; }
.stat__label { display: block; margin-top: 6px; color: var(--text-muted); font-size: 0.82rem; letter-spacing: 0.04em; text-transform: uppercase; }

/* ==========================================================================
   Materials
   ========================================================================== */
.materials { padding: 130px 0; background: var(--bg-elevated); }
.materials__grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.material-card {
  background: var(--bg-primary);
  border: 1px solid var(--border-hairline);
  padding: 36px 30px;
  border-radius: 4px;
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), border-color 0.3s var(--ease), background 0.3s var(--ease);
}
.material-card:hover { transform: translateY(-6px); border-color: var(--accent-gold); background: var(--bg-elevated-alt); }
.material-card__icon { display: inline-flex; width: 44px; height: 44px; color: var(--text-body); margin-bottom: 22px; transition: color 0.3s var(--ease); }
.material-card:hover .material-card__icon { color: var(--accent-gold); }
.material-card h3 { font-family: var(--font-heading); color: var(--text-heading); font-size: 1.15rem; letter-spacing: 0.02em; margin-bottom: 10px; }
.material-card p { font-size: 0.95rem; line-height: 1.6; margin: 0; }

/* ==========================================================================
   Process
   ========================================================================== */
.process { padding: 130px 0; }
.process__list {
  position: relative;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 40px;
}
.process__list::before {
  content: '';
  position: absolute;
  top: 20px; left: 0; right: 0; height: 1px;
  background: var(--border-hairline-alt);
}
.process__list::after {
  content: '';
  position: absolute;
  top: 20px; left: 0; height: 1px; width: 100%;
  background: var(--accent-gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 1.1s var(--ease);
}
.process__list.is-visible::after { transform: scaleX(1); }
.process__step {
  position: relative;
  text-align: center;
  padding: 0 12px;
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
}
.process__list.is-visible .process__step { opacity: 1; transform: translateY(0); }
.process__step:nth-child(1) { transition-delay: 0.15s; }
.process__step:nth-child(2) { transition-delay: 0.3s; }
.process__step:nth-child(3) { transition-delay: 0.45s; }
.process__step:nth-child(4) { transition-delay: 0.6s; }
.process__number {
  position: relative;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px; height: 40px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 1px solid var(--accent-gold);
  color: var(--accent-gold);
  font-family: var(--font-heading);
  font-weight: 600;
  margin-bottom: 20px;
}
.process__step h3 { font-family: var(--font-heading); color: var(--text-heading); font-size: 1.05rem; margin-bottom: 8px; }
.process__step p { font-size: 0.92rem; line-height: 1.6; max-width: 220px; margin: 0 auto; }

/* ==========================================================================
   Projects
   ========================================================================== */
.projects { padding: 130px 0; background: var(--bg-elevated); }
.projects__filters { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-bottom: 48px; }
.filter-btn {
  background: transparent;
  border: 1px solid var(--border-hairline);
  color: var(--text-body);
  font-family: var(--font-heading);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.78rem;
  padding: 10px 22px;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.25s var(--ease), border-color 0.25s var(--ease), color 0.25s var(--ease);
}
.filter-btn:hover { border-color: var(--accent-gold); color: var(--text-heading); }
.filter-btn.is-active { background: var(--accent-gold); border-color: var(--accent-gold); color: var(--bg-primary); }

.projects__grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.project-card {
  position: relative;
  display: block;
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  cursor: pointer;
  color: inherit;
  opacity: 1;
  transform: scale(1);
  transition: opacity 0.35s var(--ease), transform 0.35s var(--ease);
}
.project-card.is-filtered-out { opacity: 0; transform: scale(0.92); pointer-events: none; }
.project-card[hidden] { display: none; }
.project-card__frame {
  display: block;
  position: relative;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  border-radius: 4px;
  background: var(--bg-primary);
}
.project-card__frame img {
  width: 100%; height: 100%;
  object-fit: cover;
  filter: grayscale(100%) contrast(1.05);
  transition: transform 0.6s var(--ease);
  display: block;
}
.project-card:hover .project-card__frame img,
.project-card:focus-visible .project-card__frame img { transform: scale(1.08); }
.project-card__frame::after {
  content: '';
  position: absolute; inset: 0;
  border: 1px solid transparent;
  transition: border-color 0.3s var(--ease);
  pointer-events: none;
}
.project-card:hover .project-card__frame::after,
.project-card:focus-visible .project-card__frame::after { border-color: var(--accent-gold); }
.project-card__caption {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  padding: 22px 20px;
  background: linear-gradient(to top, rgba(10, 10, 12, 0.92), rgba(10, 10, 12, 0));
  display: flex;
  flex-direction: column;
  gap: 4px;
  transform: translateY(10px);
  opacity: 0;
  transition: transform 0.35s var(--ease), opacity 0.35s var(--ease);
}
.project-card:hover .project-card__caption,
.project-card:focus-visible .project-card__caption { transform: translateY(0); opacity: 1; }
.project-card__name { font-family: var(--font-heading); color: var(--text-heading); font-size: 1rem; letter-spacing: 0.02em; }
.project-card__meta { color: var(--accent-gold); font-size: 0.8rem; letter-spacing: 0.04em; text-transform: uppercase; }

/* ==========================================================================
   Lightbox
   ========================================================================== */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.35s var(--ease), visibility 0s linear 0.35s;
}
.lightbox.is-open { opacity: 1; visibility: visible; transition: opacity 0.35s var(--ease); }
.lightbox__backdrop { position: absolute; inset: 0; background: rgba(6, 6, 7, 0.94); }
.lightbox__figure {
  position: relative;
  z-index: 1;
  max-width: min(1100px, 92vw);
  max-height: 88vh;
  margin: 0;
  text-align: center;
  transform: scale(0.96);
  transition: transform 0.35s var(--ease);
}
.lightbox.is-open .lightbox__figure { transform: scale(1); }
.lightbox__figure img {
  max-width: 100%;
  max-height: 78vh;
  object-fit: contain;
  filter: grayscale(100%);
  border: 1px solid var(--border-hairline-alt);
  background: var(--bg-elevated);
  margin: 0 auto;
}
.lightbox__figure figcaption { margin-top: 18px; color: var(--text-heading); font-family: var(--font-heading); letter-spacing: 0.04em; }
.lightbox__close, .lightbox__arrow {
  position: absolute;
  z-index: 2;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.25);
  color: var(--text-heading);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  transition: border-color 0.25s var(--ease), color 0.25s var(--ease);
}
.lightbox__close:hover, .lightbox__arrow:hover { border-color: var(--accent-gold); color: var(--accent-gold); }
.lightbox__close { top: 24px; right: 24px; width: 44px; height: 44px; }
.lightbox__arrow { top: 50%; transform: translateY(-50%); width: 52px; height: 52px; }
.lightbox__arrow--prev { left: 24px; }
.lightbox__arrow--next { right: 24px; }

/* ==========================================================================
   Contact
   ========================================================================== */
.contact { padding: 130px 0; }
.contact__grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.contact-card {
  border: 1px solid var(--border-hairline);
  padding: 32px 26px;
  border-radius: 4px;
  text-align: center;
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), border-color 0.3s var(--ease);
}
.contact-card:hover { transform: translateY(-4px); border-color: var(--accent-gold); }
.contact-card h3 { font-family: var(--font-heading); color: var(--accent-gold); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.1em; margin-bottom: 14px; }
.contact-card p { margin: 0; line-height: 1.6; }
.contact-card a { color: var(--text-heading); text-decoration: none; border-bottom: 1px solid transparent; transition: border-color 0.25s var(--ease), color 0.25s var(--ease); }
.contact-card a:hover { color: var(--accent-gold); border-color: var(--accent-gold); }

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer { background: var(--bg-elevated); border-top: 1px solid var(--border-hairline); padding-top: 72px; }
.site-footer__inner { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 48px; padding-bottom: 56px; }
.site-footer__brand p { color: var(--text-muted); margin: 16px 0 0; font-size: 0.92rem; line-height: 1.6; max-width: 280px; }
.site-footer__nav h3, .site-footer__materials h3 { font-family: var(--font-heading); color: var(--text-heading); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.1em; margin: 0 0 18px; }
.site-footer__nav ul, .site-footer__materials ul { list-style: none; display: flex; flex-direction: column; gap: 12px; }
.site-footer__nav a { color: var(--text-body); text-decoration: none; transition: color 0.25s var(--ease); }
.site-footer__nav a:hover { color: var(--accent-gold); }
.site-footer__materials li { color: var(--text-body); font-size: 0.95rem; }
.site-footer__bottom { border-top: 1px solid var(--border-hairline); padding: 24px 0; text-align: center; }
.site-footer__bottom p { color: var(--text-muted); font-size: 0.85rem; margin: 0; }

/* ==========================================================================
   Back to top
   ========================================================================== */
.back-to-top {
  position: fixed;
  right: 28px; bottom: 28px;
  width: 48px; height: 48px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 1px solid var(--border-hairline);
  color: var(--text-heading);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  z-index: 500;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), visibility 0s linear 0.3s, border-color 0.3s var(--ease), color 0.3s var(--ease);
}
.back-to-top.is-visible { opacity: 1; visibility: visible; transform: translateY(0); transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), border-color 0.3s var(--ease), color 0.3s var(--ease); }
.back-to-top:hover { border-color: var(--accent-gold); color: var(--accent-gold); }

/* ==========================================================================
   Section anchor offset (accounts for fixed header)
   ========================================================================== */
section[id] { scroll-margin-top: var(--header-h); }

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 1024px) {
  .about__grid { grid-template-columns: 1fr; gap: 40px; }
  .materials__grid { grid-template-columns: repeat(2, 1fr); }
  .process__list { grid-template-columns: repeat(2, 1fr); gap: 48px 24px; }
  .process__list::before, .process__list::after { display: none; }
  .projects__grid { grid-template-columns: repeat(2, 1fr); }
  .contact__grid { grid-template-columns: repeat(2, 1fr); }
  .site-footer__inner { grid-template-columns: 1fr 1fr; }
  .site-footer__brand { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  .nav-toggle { display: flex; }
  .main-nav {
    position: fixed;
    inset: 0;
    background: var(--bg-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    transform: translateX(100%);
    transition: transform 0.4s var(--ease);
    z-index: 920;
  }
  .main-nav.is-open { transform: translateX(0); }
  .main-nav__list { flex-direction: column; gap: 30px; text-align: center; }
  .main-nav__link { font-size: 1.15rem; }
}

@media (max-width: 640px) {
  .container { padding: 0 20px; }
  .materials__grid { grid-template-columns: 1fr; }
  .process__list { grid-template-columns: 1fr; gap: 40px; }
  .projects__grid { grid-template-columns: 1fr; }
  .contact__grid { grid-template-columns: 1fr; }
  .site-footer__inner { grid-template-columns: 1fr; }
  .about__stats { grid-template-columns: 1fr 1fr; }
  .hero__controls { right: 20px; bottom: 24px; }
  .hero__scroll-cue { display: none; }
  .about, .materials, .process, .projects, .contact { padding: 90px 0; }
}

/* ==========================================================================
   Reduced motion
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .hero__slide.is-active { animation: none; transform: none; }
  .marquee__track { animation: none; }
  .hero__scroll-cue-line::after { animation: none; opacity: 1; top: 50%; transform: translate(-50%, -50%); }
}