/* ============================================================
   Sigma Metaliks — design system
   ============================================================ */

:root {
  --color-bg: #F7F6F4;
  --color-text-primary: #1C1B1A;
  --color-text-secondary: #75726C;
  --color-accent: #B5652D;
  --color-dark-section: #161514;

  --color-surface: #FFFFFF;
  --color-surface-alt: #EFEDE9;
  --border-hairline: rgba(28, 27, 26, 0.10);
  --border-hairline-light: rgba(247, 246, 244, 0.16);
  --shadow-card: 0 1px 2px rgba(28,27,26,0.04), 0 12px 28px rgba(28,27,26,0.06);
  --shadow-card-hover: 0 4px 10px rgba(28,27,26,0.06), 0 24px 48px rgba(28,27,26,0.10);

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --dur-fast: 220ms;
  --dur-mid: 420ms;
  --dur-slow: 700ms;

  --container-max: 1240px;
  --gutter: 20px;
  --section-pad: 72px;

  --fs-hero: clamp(2.25rem, 5.6vw + 0.6rem, 5.25rem);
  --fs-page-title: clamp(2rem, 4.4vw + 0.6rem, 3.75rem);
  --fs-h2: clamp(1.75rem, 2.8vw + 0.7rem, 3rem);
  --fs-h3: clamp(1.08rem, 0.7vw + 0.95rem, 1.3rem);
}

@media (min-width: 640px)  { :root { --gutter: 32px; --section-pad: 96px; } }
@media (min-width: 1024px) { :root { --gutter: 48px; --section-pad: 120px; } }

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text-primary);
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img, video, iframe, canvas, svg { max-width: 100%; }
img { display: block; height: auto; }
a { color: inherit; text-decoration: none; }
ul, ol { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4, p, dl, dd, figure { margin: 0; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }
table { border-collapse: collapse; }

/* Kill intrinsic min-width so grid/flex children can shrink on small screens */
input, textarea, select { font: inherit; color: inherit; width: 100%; min-width: 0; max-width: 100%; }
.grid-safe > *, .contact-grid > *, .products-grid > *, .capabilities-grid > *,
.gallery-grid > *, .stats-grid > *, .footer-grid > *, .split > *, .process-strip > * { min-width: 0; }

h1, h2, h3 { font-weight: 600; letter-spacing: -0.02em; line-height: 1.1; overflow-wrap: break-word; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; }
}

.skip-link { position: absolute; left: -999px; top: 0; background: var(--color-dark-section); color: #fff; padding: 12px 20px; z-index: 1000; }
.skip-link:focus { left: 16px; top: 16px; }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 3px; }

.container { width: 100%; max-width: var(--container-max); margin: 0 auto; padding-left: var(--gutter); padding-right: var(--gutter); }

/* ---------- Reveal ---------- */
.reveal { opacity: 0; transform: translateY(20px); transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease); }
.reveal.is-visible { opacity: 1; transform: none; }
.no-js .reveal { opacity: 1; transform: none; }

/* ---------- Type ---------- */
.eyebrow { font-size: 0.75rem; font-weight: 600; letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-accent); margin: 0 0 14px; }
.eyebrow--light { color: #E3B48E; }

.section__head { max-width: 640px; margin-bottom: 48px; }
.section__head h2 { margin-bottom: 16px; font-size: var(--fs-h2); }
.section__intro { color: var(--color-text-secondary); font-size: 1.02rem; }
.section__head--light h2 { color: #fff; }
.section__head--center { margin-left: auto; margin-right: auto; text-align: center; }
.section__intro--light { color: rgba(247,246,244,0.68); }
@media (min-width: 640px) { .section__head { margin-bottom: 60px; } .section__intro { font-size: 1.08rem; } }

.lede { font-size: 1.05rem; color: var(--color-text-secondary); }
.prose p + p { margin-top: 18px; }
.prose strong { color: var(--color-text-primary); font-weight: 600; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 14px 26px; border-radius: 3px;
  font-size: 0.92rem; font-weight: 500;
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
  text-align: center;
}
.btn--primary { background: var(--color-accent); color: #fff; }
.btn--primary:hover { background: #9c5526; transform: translateY(-1px); }
.btn--ghost { border: 1px solid rgba(247,246,244,0.35); color: #fff; }
.btn--ghost:hover { border-color: #fff; background: rgba(247,246,244,0.08); }
.btn--outline { border: 1px solid var(--border-hairline); color: var(--color-text-primary); }
.btn--outline:hover { border-color: var(--color-text-primary); }
.btn--small { padding: 10px 18px; font-size: 0.82rem; }
.btn--full { width: 100%; padding: 16px 26px; }

/* ---------- Header / Nav ---------- */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; width: 100%;
  z-index: 100; padding: 16px 0;
  border-bottom: 1px solid transparent;
  transition: background var(--dur-mid) var(--ease), padding var(--dur-mid) var(--ease), border-color var(--dur-mid) var(--ease);
}
.site-header--solid,
.site-header.is-scrolled {
  background: rgba(247,246,244,0.88);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-color: var(--border-hairline);
  padding: 12px 0;
}
.nav { display: flex; align-items: center; justify-content: space-between; gap: 16px; }

.nav__brand { font-size: 1rem; font-weight: 700; letter-spacing: -0.01em; color: #fff; white-space: nowrap; transition: color var(--dur-mid) var(--ease); }
.nav__brand span { color: var(--color-accent); }
.site-header--solid .nav__brand,
.is-scrolled .nav__brand { color: var(--color-text-primary); }

.nav__links { display: none; align-items: center; gap: 30px; font-size: 0.9rem; font-weight: 500; color: rgba(255,255,255,0.9); }
.site-header--solid .nav__links,
.is-scrolled .nav__links { color: var(--color-text-primary); }
.nav__links a { position: relative; padding: 10px 0; white-space: nowrap; }
.nav__links a::after { content: ""; position: absolute; left: 0; right: 100%; bottom: 6px; height: 1px; background: currentColor; transition: right var(--dur-mid) var(--ease); }
.nav__links a:hover::after, .nav__links a.is-active::after { right: 0; }
.nav__links a.is-active { color: var(--color-accent); }

.nav__cta { display: none; }

.nav__toggle { display: flex; flex-direction: column; justify-content: center; gap: 5px; width: 40px; height: 40px; align-items: center; flex: none; }
.nav__toggle span { display: block; width: 22px; height: 1.5px; background: #fff; transition: background var(--dur-mid) var(--ease), transform var(--dur-fast) var(--ease), opacity var(--dur-fast) var(--ease); }
.site-header--solid .nav__toggle span,
.is-scrolled .nav__toggle span { background: var(--color-text-primary); }
body.nav-open .nav__toggle span { background: #fff; }
body.nav-open .nav__toggle span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
body.nav-open .nav__toggle span:nth-child(2) { opacity: 0; }
body.nav-open .nav__toggle span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }
body.nav-open { overflow: hidden; }

body.nav-open .nav__links {
  display: flex; position: fixed; inset: 0;
  flex-direction: column; justify-content: center; align-items: flex-start;
  gap: 22px; padding: 0 32px;
  background: var(--color-dark-section); color: #fff;
  font-size: 1.45rem; z-index: 90;
}
body.nav-open .nav__links a.is-active { color: var(--color-accent); }
/* Toggle must sit above the fullscreen overlay or the menu cannot be closed */
body.nav-open .nav__toggle { position: relative; z-index: 95; }

@media (min-width: 960px) {
  .nav__links { display: flex; }
  .nav__cta { display: inline-flex; }
  .nav__toggle { display: none; }
}

/* ---------- Home hero ---------- */
.hero { position: relative; display: flex; align-items: center; overflow: hidden; background: var(--color-dark-section); min-height: 640px; min-height: 100svh; }
.hero__media { position: absolute; inset: 0; background-image: url('../images/hero-welding.jpg'); background-size: cover; background-position: center 38%; }
.hero__scrim { position: absolute; inset: 0; background: linear-gradient(180deg, rgba(22,21,20,0.58) 0%, rgba(22,21,20,0.74) 55%, rgba(22,21,20,0.95) 100%), linear-gradient(90deg, rgba(22,21,20,0.78) 0%, rgba(22,21,20,0.34) 60%, rgba(22,21,20,0.7) 100%); }
.hero__content { position: relative; z-index: 2; padding-top: 108px; padding-bottom: 84px; }
.hero h1 { color: #fff; font-size: var(--fs-hero); max-width: 16ch; }
.hero__sub { color: rgba(247,246,244,0.74); font-size: 1.02rem; max-width: 48ch; margin-top: 22px; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
@media (min-width: 640px) { .hero__sub { font-size: 1.12rem; margin-top: 26px; } .hero__actions { gap: 16px; margin-top: 40px; } }

/* ---------- Inner page header ---------- */
.page-header { position: relative; background: var(--color-dark-section); color: #fff; padding: 132px 0 56px; }
.page-header::after { content: ""; position: absolute; left: var(--gutter); bottom: 0; width: 56px; height: 2px; background: var(--color-accent); }
.page-header h1 { font-size: var(--fs-page-title); color: #fff; max-width: 18ch; }
.page-header p { margin-top: 18px; color: rgba(247,246,244,0.66); max-width: 56ch; font-size: 1.02rem; }
.page-header p.eyebrow { margin-top: 0; font-size: 0.75rem; color: #E3B48E; max-width: none; }
/* Fixed header offset so anchor jumps don't hide the target behind the nav */
[id] { scroll-margin-top: 96px; }
@media (min-width: 640px) { .page-header { padding: 168px 0 76px; } }
@media (min-width: 1024px) { .page-header { padding: 196px 0 92px; } }

/* ---------- Sections ---------- */
.section { padding: var(--section-pad) 0; }
.section--alt { background: var(--color-surface-alt); }
.section--dark { background: var(--color-dark-section); color: #fff; }
.section--tight { padding-top: calc(var(--section-pad) * 0.6); }

/* ---------- Split (text + image) ---------- */
.split { display: grid; grid-template-columns: 1fr; gap: 36px; align-items: center; }
.split__media img { width: 100%; border-radius: 3px; box-shadow: var(--shadow-card); }
@media (min-width: 900px) { .split { grid-template-columns: 1fr 1fr; gap: 64px; } .split--reverse .split__media { order: 2; } }

/* ---------- Capabilities ---------- */
.capabilities-grid { display: grid; grid-template-columns: 1fr; gap: 1px; background: var(--border-hairline); border: 1px solid var(--border-hairline); }
.capability-card { background: var(--color-bg); padding: 32px 24px; transition: background var(--dur-mid) var(--ease); }
.capability-card:hover { background: var(--color-surface); }
.capability-card__icon { width: 32px; height: 32px; color: var(--color-accent); margin-bottom: 20px; }
.capability-card h3 { font-size: var(--fs-h3); margin-bottom: 10px; }
.capability-card p { color: var(--color-text-secondary); font-size: 0.94rem; }
@media (min-width: 640px)  { .capability-card { padding: 40px 32px; } .capabilities-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .capabilities-grid { grid-template-columns: repeat(3, 1fr); } }

/* ---------- Process strip ---------- */
.process-strip { display: grid; grid-template-columns: 1fr; gap: var(--gutter); margin-top: 56px; }
.process-strip img { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; border-radius: 3px; transition: transform var(--dur-slow) var(--ease); }
.process-strip figure { overflow: hidden; }
.process-strip figure:hover img { transform: scale(1.03); }
.process-strip figcaption { margin-top: 14px; font-size: 0.8rem; letter-spacing: 0.06em; text-transform: uppercase; color: var(--color-text-secondary); }
@media (min-width: 640px) { .process-strip { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 900px) { .process-strip { grid-template-columns: repeat(4, 1fr); } }

/* ---------- Products ---------- */
.products-grid { display: grid; grid-template-columns: 1fr; gap: var(--gutter); }
.product-card { display: block; }
.product-card__media { aspect-ratio: 4 / 3; overflow: hidden; border-radius: 3px; background: var(--color-surface); box-shadow: var(--shadow-card); transition: box-shadow var(--dur-mid) var(--ease), transform var(--dur-mid) var(--ease); }
.product-card__media img { width: 100%; height: 100%; object-fit: cover; transition: transform var(--dur-slow) var(--ease); }
.product-card:hover .product-card__media { box-shadow: var(--shadow-card-hover); transform: translateY(-4px); }
.product-card:hover .product-card__media img { transform: scale(1.05); }
.product-card h3 { font-size: var(--fs-h3); margin: 18px 0 6px; }
.product-card p { color: var(--color-text-secondary); font-size: 0.92rem; }
@media (min-width: 560px)  { .products-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .products-grid { grid-template-columns: repeat(4, 1fr); } }
.products-grid--3 { grid-template-columns: 1fr; }
@media (min-width: 560px)  { .products-grid--3 { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .products-grid--3 { grid-template-columns: repeat(3, 1fr); } }

/* ---------- Product category block + gallery ---------- */
.category { padding-top: 56px; border-top: 1px solid var(--border-hairline); margin-top: 56px; }
.category:first-of-type { border-top: 0; margin-top: 0; padding-top: 0; }
.category__head { margin-bottom: 28px; }
.category__head h2 { font-size: clamp(1.5rem, 2vw + 0.8rem, 2.1rem); margin-bottom: 8px; }
.category__head p { color: var(--color-text-secondary); max-width: 60ch; font-size: 0.98rem; }

.gallery-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
@media (min-width: 640px)  { .gallery-grid { grid-template-columns: repeat(3, 1fr); gap: 16px; } }
@media (min-width: 1024px) { .gallery-grid { grid-template-columns: repeat(4, 1fr); gap: 20px; } }
.gallery-item { display: block; aspect-ratio: 4 / 3; overflow: hidden; border-radius: 3px; background: var(--color-surface); border: 1px solid var(--border-hairline); cursor: zoom-in; position: relative; }
.gallery-item img { width: 100%; height: 100%; object-fit: cover; transition: transform var(--dur-slow) var(--ease); }
.gallery-item:hover img { transform: scale(1.06); }

/* ---------- Lightbox ---------- */
.lightbox { position: fixed; inset: 0; z-index: 200; display: none; align-items: center; justify-content: center; background: rgba(22,21,20,0.94); padding: 20px; }
.lightbox.is-open { display: flex; }
.lightbox img { max-width: 100%; max-height: 82vh; object-fit: contain; border-radius: 3px; }
.lightbox__close, .lightbox__nav { position: absolute; color: #fff; font-size: 1.6rem; line-height: 1; padding: 14px; border-radius: 50%; background: rgba(247,246,244,0.1); transition: background var(--dur-fast) var(--ease); min-width: 48px; min-height: 48px; display: flex; align-items: center; justify-content: center; }
.lightbox__close:hover, .lightbox__nav:hover { background: rgba(247,246,244,0.22); }
.lightbox__close { top: 16px; right: 16px; }
.lightbox__nav--prev { left: 12px; top: 50%; transform: translateY(-50%); }
.lightbox__nav--next { right: 12px; top: 50%; transform: translateY(-50%); }
.lightbox__caption { position: absolute; bottom: 20px; left: 0; right: 0; text-align: center; color: rgba(247,246,244,0.72); font-size: 0.85rem; padding: 0 60px; }

/* ---------- Spec table ---------- */
.table-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; border: 1px solid var(--border-hairline); border-radius: 3px; background: var(--color-surface); }
.spec-table { width: 100%; min-width: 640px; font-size: 0.9rem; }
.spec-table th, .spec-table td { padding: 14px 16px; text-align: left; vertical-align: top; border-bottom: 1px solid var(--border-hairline); }
.spec-table th { background: var(--color-surface-alt); font-weight: 600; font-size: 0.78rem; letter-spacing: 0.06em; text-transform: uppercase; color: var(--color-text-secondary); white-space: nowrap; }
.spec-table tr:last-child td { border-bottom: 0; }
.spec-table td:first-child { color: var(--color-accent); font-weight: 600; }
.table-hint { font-size: 0.8rem; color: var(--color-text-secondary); margin-top: 12px; }
@media (min-width: 1024px) { .table-hint { display: none; } }

/* ---------- Stats ---------- */
.stats-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; background: var(--border-hairline-light); border: 1px solid var(--border-hairline-light); }
.stat { background: var(--color-dark-section); padding: 28px 20px; }
.stat__number { font-size: clamp(1.6rem, 3vw, 2.6rem); font-weight: 700; color: var(--color-accent); margin-bottom: 8px; }
.stat__number--text { font-size: clamp(1.2rem, 2.2vw, 1.9rem); }
.stat__label { font-weight: 600; margin-bottom: 6px; font-size: 0.95rem; }
.stat__desc { color: rgba(247,246,244,0.6); font-size: 0.85rem; }
@media (min-width: 640px)  { .stat { padding: 36px 26px; } }
@media (min-width: 1024px) { .stats-grid { grid-template-columns: repeat(4, 1fr); } }

/* ---------- Value list (quality principles) ---------- */
.value-list { display: grid; grid-template-columns: 1fr; gap: 1px; background: var(--border-hairline); border: 1px solid var(--border-hairline); }
.value-list__item { background: var(--color-bg); padding: 28px 24px; }
.value-list__item h3 { font-size: 1.05rem; margin-bottom: 8px; color: var(--color-accent); }
.value-list__item p { color: var(--color-text-secondary); font-size: 0.94rem; }
@media (min-width: 700px)  { .value-list { grid-template-columns: repeat(2, 1fr); } .value-list__item { padding: 34px 30px; } }
@media (min-width: 1100px) { .value-list { grid-template-columns: repeat(3, 1fr); } }

/* ---------- CTA band ---------- */
.cta-band { background: var(--color-dark-section); color: #fff; text-align: center; padding: var(--section-pad) 0; }
.cta-band h2 { font-size: var(--fs-h2); margin-bottom: 16px; }
.cta-band p { color: rgba(247,246,244,0.68); max-width: 52ch; margin: 0 auto 30px; }
.cta-band__actions { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; }

/* ---------- Contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr; gap: 48px; }
@media (min-width: 1000px) { .contact-grid { grid-template-columns: 1fr 1fr; gap: 64px; } }

.contact-details { margin-top: 32px; display: grid; gap: 22px; }
.contact-details dt { font-weight: 600; margin-bottom: 4px; font-size: 0.95rem; }
.contact-details dd { margin: 0; color: var(--color-text-secondary); font-size: 0.95rem; overflow-wrap: anywhere; }
.contact-details dd a { display: inline-block; padding: 8px 0; }
.contact-details a:hover { color: var(--color-accent); }

.contact-map { margin-top: 32px; border-radius: 3px; overflow: hidden; border: 1px solid var(--border-hairline); aspect-ratio: 16 / 10; }
.contact-map iframe { width: 100%; height: 100%; border: 0; display: block; filter: grayscale(0.3); }

.enquiry-form { background: var(--color-surface); border: 1px solid var(--border-hairline); border-radius: 4px; padding: 26px 20px; display: grid; gap: 18px; align-self: start; }
@media (min-width: 640px) { .enquiry-form { padding: 36px 32px; } }
.form-row { display: grid; gap: 7px; }
.form-row--half { display: grid; grid-template-columns: 1fr; gap: 18px; }
@media (min-width: 560px) { .form-row--half { grid-template-columns: 1fr 1fr; } }
.form-row label { font-size: 0.82rem; font-weight: 500; color: var(--color-text-secondary); }
.form-row label span { color: var(--color-accent); }
.form-row input, .form-row textarea, .form-row select {
  border: 1px solid var(--border-hairline); background: var(--color-bg); border-radius: 3px;
  padding: 12px 13px;
  font-size: 1rem; /* >=16px, else iOS Safari zooms the viewport on focus */
  transition: border-color var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}
.form-row input:focus, .form-row textarea:focus, .form-row select:focus { border-color: var(--color-accent); background: var(--color-surface); outline: none; }
.form-row textarea { resize: vertical; min-height: 110px; }
.form-note { font-size: 0.8rem; color: var(--color-text-secondary); text-align: center; margin: 0; }
.form-note.is-success { color: var(--color-accent); font-weight: 500; }

/* ---------- Footer ---------- */
.site-footer { background: var(--color-dark-section); color: rgba(247,246,244,0.7); padding: 56px 0 0; }
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 32px; padding-bottom: 40px; border-bottom: 1px solid var(--border-hairline-light); }
.footer-grid h4 { font-size: 0.78rem; letter-spacing: 0.12em; text-transform: uppercase; color: rgba(247,246,244,0.45); margin-bottom: 14px; font-weight: 600; }
.footer-grid p { font-size: 0.9rem; margin-bottom: 10px; }
.footer-about p { margin-top: 14px; max-width: 34ch; }
.footer-grid nav { display: grid; gap: 2px; font-size: 0.9rem; }
.footer-grid nav a, .footer-contact a { display: inline-block; padding: 8px 0; }
.footer-grid nav a:hover, .footer-contact a:hover { color: #fff; }
.footer-contact a { overflow-wrap: anywhere; }
.footer-bottom { padding: 20px 0; font-size: 0.78rem; display: flex; flex-wrap: wrap; gap: 6px 18px; justify-content: space-between; }
.footer-bottom p { margin: 0; }
@media (min-width: 700px)  { .site-footer { padding-top: 72px; } .footer-grid { grid-template-columns: 1.5fr 1fr 1.2fr; gap: 40px; } }