/* ==========================================================================
   High Temperature Lab — stylesheet
   ========================================================================== */

:root {
  --ink: #211d19;
  --ink-soft: #4a443d;
  --paper: #f7f4ee;
  --paper-strong: #ffffff;
  --ember: #b1551f;
  --ember-dark: #8c4118;
  --line: rgba(33, 29, 25, 0.22);
  --hero-image: url("https://images.unsplash.com/photo-1549891472-991e6bc75d1e?fm=jpg&q=80&w=2400&auto=format&fit=crop");

  --font-display: "Jost", "Segoe UI", sans-serif;
  --font-serif: "Fraunces", Georgia, serif;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 400;
  color: var(--ink);
  background: var(--ink);
  -webkit-font-smoothing: antialiased;
}

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

a { color: inherit; text-decoration: none; }

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

button { font-family: inherit; cursor: pointer; }

/* Fixed backdrop image shared by hero + content sections, so overlays read
   as tinted panels floating over one continuous photograph. */
main::before {
  content: "";
  position: fixed;
  inset: 0;
  background-image: var(--hero-image);
  background-size: cover;
  background-position: center 30%;
  z-index: -1;
}

/* ---------- Header ---------- */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: linear-gradient(to bottom, rgba(15, 13, 11, 0.55), rgba(15, 13, 11, 0));
  transition: background 0.3s ease;
}

.site-header.scrolled {
  background: rgba(20, 17, 15, 0.92);
  box-shadow: 0 2px 18px rgba(0, 0, 0, 0.25);
}

.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 22px 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.logo {
  font-size: 13px;
  line-height: 1.35;
  letter-spacing: 0.14em;
  font-weight: 400;
  color: #fff;
  text-transform: uppercase;
  white-space: nowrap;
}

.main-nav {
  display: flex;
  gap: 40px;
}

.main-nav a {
  color: #fff;
  font-size: 14px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  position: relative;
  padding-bottom: 4px;
}

.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 1px;
  background: var(--ember);
  transition: width 0.25s ease;
}

.main-nav a:hover::after,
.main-nav a:focus-visible::after {
  width: 100%;
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 18px;
}

.lang-switch {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  letter-spacing: 0.08em;
}

.lang-btn {
  background: none;
  border: none;
  color: rgba(255, 255, 255, 0.6);
  padding: 4px 2px;
}

.lang-btn.active {
  color: #fff;
  border-bottom: 1px solid var(--ember);
}

.lang-sep {
  color: rgba(255, 255, 255, 0.35);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 30px;
  height: 24px;
  background: none;
  border: none;
  padding: 0;
}

.nav-toggle span {
  display: block;
  height: 1px;
  background: #fff;
  width: 100%;
}

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

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 0 24px;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(20, 16, 12, 0.35) 0%, rgba(20, 16, 12, 0.15) 45%, rgba(20, 16, 12, 0.55) 100%);
}

.hero-title {
  position: relative;
  z-index: 1;
  margin: 0;
  color: #fff;
  font-family: var(--font-display);
  font-weight: 300;
  text-transform: uppercase;
  letter-spacing: 0.28em;
  font-size: clamp(2.1rem, 5.5vw, 4.4rem);
  line-height: 1.35;
}

/* ---------- Shared section chrome ---------- */

.section-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 100px 40px;
}

.section-title {
  text-align: center;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(1.9rem, 3.4vw, 2.6rem);
  margin: 0 0 22px;
  color: var(--ink);
}

.title-rule {
  width: 90px;
  height: 2px;
  background: var(--ink);
  margin: 0 auto 60px;
  position: relative;
}

.title-rule::after {
  content: "";
  position: absolute;
  left: 50%;
  top: -3px;
  transform: translateX(-50%);
  width: 8px;
  height: 8px;
  background: var(--ember);
  border-radius: 50%;
}

/* ---------- Services ---------- */

.services {
  position: relative;
  background: rgba(247, 244, 238, 0.86);
}

.services-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 46px 60px;
}

.services-col li {
  font-weight: 500;
  font-size: 1.02rem;
  line-height: 1.55;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.services-col li:last-child {
  border-bottom: none;
}

/* ---------- Contact ---------- */

.contact {
  position: relative;
  background: rgba(255, 255, 255, 0.9);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 70px;
}

.contact-form-wrap h3,
.office-info h3 {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 1.5rem;
  margin: 0 0 14px;
}

.contact-intro {
  color: var(--ink-soft);
  margin: 0 0 30px;
  line-height: 1.6;
}

.form-row {
  margin-bottom: 18px;
}

.form-row label {
  display: block;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
  color: var(--ink-soft);
  margin-bottom: 6px;
}

.form-row input,
.form-row textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.85);
  font-family: inherit;
  font-size: 0.98rem;
  color: var(--ink);
  border-radius: 2px;
}

.form-row input:focus,
.form-row textarea:focus {
  outline: none;
  border-color: var(--ember);
  box-shadow: 0 0 0 3px rgba(177, 85, 31, 0.15);
}

.form-row textarea {
  resize: vertical;
  min-height: 130px;
}

.hp-field {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.submit-btn {
  background: var(--ink);
  color: #fff;
  border: none;
  padding: 14px 36px;
  font-size: 0.95rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border-radius: 2px;
  transition: background 0.2s ease;
}

.submit-btn:hover,
.submit-btn:focus-visible {
  background: var(--ember-dark);
}

.submit-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.form-status {
  margin: 14px 0 0;
  font-size: 0.92rem;
  min-height: 1.2em;
}

.form-status.success { color: #2f6d3f; }
.form-status.error { color: #a4322a; }

.office-info p {
  line-height: 1.7;
  margin: 0 0 24px;
  color: var(--ink-soft);
}

.office-info strong {
  color: var(--ink);
  font-weight: 600;
}

.office-info a:hover {
  color: var(--ember);
}

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

.footer-strip {
  height: 220px;
}

.site-footer {
  background: #14100d;
  color: rgba(255, 255, 255, 0.6);
  text-align: center;
  padding: 22px 20px;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
}

/* ---------- Responsive ---------- */

@media (max-width: 880px) {
  .services-grid,
  .contact-grid {
    grid-template-columns: 1fr;
  }

  .section-inner {
    padding: 70px 24px;
  }

  .main-nav {
    position: fixed;
    top: 0;
    right: 0;
    height: 100vh;
    width: min(78vw, 320px);
    background: rgba(18, 15, 13, 0.98);
    flex-direction: column;
    align-items: flex-start;
    padding: 110px 32px 40px;
    gap: 28px;
    transform: translateX(100%);
    transition: transform 0.3s ease;
  }

  .main-nav.open {
    transform: translateX(0);
  }

  .nav-toggle {
    display: flex;
  }

  .header-inner {
    padding: 18px 22px;
  }

  .logo {
    font-size: 11px;
  }
}

@media (max-width: 480px) {
  .footer-strip {
    height: 140px;
  }
}

/* Respect reduced motion preference */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}