/* ============================================
   MERCER INTERNATIONAL — Oil Water Separators
   POC Redesign · Dark Industrial Theme
   ============================================ */

:root {
  --steel: #1a1f2e;
  --steel-2: #252b3d;
  --steel-3: #2f3650;
  --red: #c8312b;
  --red-hover: #e03930;
  --grey: #8b8e96;
  --grey-light: #b8bbc2;
  --white: #ffffff;
  --off-white: #f4f5f7;
  --line: rgba(255,255,255,0.08);
  --line-dark: rgba(0,0,0,0.08);
  --radius: 8px;
  --max-w: 1200px;
  --section-pad: 96px;
  --font: 'Inter', 'Segoe UI', Roboto, -apple-system, sans-serif;
}

/* ---- Reset ---- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font);
  line-height: 1.6;
  color: var(--white);
  background: var(--steel);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

/* ---- Layout ---- */
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 24px; }
.section { padding: var(--section-pad) 0; }
.section-dark { background: var(--steel); color: var(--white); }
.section-light { background: var(--off-white); color: var(--steel); }

/* ---- Typography ---- */
h1 { font-size: clamp(2rem, 5vw, 3.5rem); font-weight: 800; line-height: 1.1; letter-spacing: -0.02em; }
h2 { font-size: clamp(1.75rem, 4vw, 2.75rem); font-weight: 700; line-height: 1.15; letter-spacing: -0.015em; }
h3 { font-size: clamp(1.25rem, 2.5vw, 1.5rem); font-weight: 600; line-height: 1.3; }
.accent { color: var(--red); }
.section-label {
  text-transform: uppercase;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--red);
  margin-bottom: 12px;
}
.section-sub { color: var(--grey-light); font-size: 1.125rem; margin-top: 12px; }
.section-light .section-sub { color: var(--grey); }
.section-header { text-align: center; max-width: 760px; margin: 0 auto 64px; }
h2 strong { font-weight: 800; }

/* ---- Buttons ---- */
.btn {
  display: inline-block;
  padding: 14px 28px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.2s;
  cursor: pointer;
  border: none;
  text-align: center;
}
.btn-primary { background: var(--red); color: var(--white); }
.btn-primary:hover { background: var(--red-hover); transform: translateY(-1px); }
.btn-secondary { background: transparent; color: var(--white); border: 2px solid var(--line); }
.btn-secondary:hover { border-color: var(--white); background: rgba(255,255,255,0.05); }
.btn-lg { padding: 18px 36px; font-size: 1.05rem; }
.btn-block { display: block; width: 100%; }
.section-light .btn-secondary { color: var(--steel); border-color: rgba(0,0,0,0.15); }
.section-light .btn-secondary:hover { border-color: var(--steel); background: rgba(0,0,0,0.04); }

/* ---- Nav ---- */
#nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(26,31,46,0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: var(--max-w); margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 24px;
}
.nav-brand-name { font-weight: 800; font-size: 1.25rem; letter-spacing: -0.02em; }
#nav-links { display: flex; gap: 28px; list-style: none; align-items: center; }
#nav-links a { font-size: 0.9rem; font-weight: 500; opacity: 0.8; transition: opacity 0.2s; }
#nav-links a:hover { opacity: 1; }
.nav-cta {
  background: var(--red); padding: 8px 20px; border-radius: var(--radius);
  color: var(--white) !important; opacity: 1 !important;
}
.nav-cta:hover { background: var(--red-hover); }
.nav-toggle { display: none; }

/* ---- Hero ---- */
#hero { position: relative; min-height: 92vh; display: flex; flex-direction: column; justify-content: center; }
.hero-bg { position: absolute; inset: 0; z-index: 0; }
.hero-bg img { width: 100%; height: 100%; object-fit: cover; }
.hero-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(26,31,46,0.92) 0%, rgba(26,31,46,0.7) 60%, rgba(26,31,46,0.85) 100%);
}
.hero-content {
  position: relative; z-index: 2;
  max-width: var(--max-w); margin: 0 auto;
  padding: 120px 24px 80px;
}
.hero-eyebrow { font-size: 0.9rem; color: var(--grey); margin-bottom: 20px; text-transform: uppercase; letter-spacing: 0.08em; }
.hero-sub { font-size: 1.25rem; color: var(--grey-light); max-width: 580px; margin: 24px 0; }
.hero-cta { display: flex; gap: 16px; margin-top: 32px; flex-wrap: wrap; }
.trust-bar {
  position: relative; z-index: 2;
  background: rgba(200,49,43,0.1);
  border-top: 1px solid rgba(200,49,43,0.2);
  padding: 16px 24px;
}
.trust-bar-inner {
  max-width: var(--max-w); margin: 0 auto;
  display: flex; gap: 12px; align-items: center; justify-content: center;
  flex-wrap: wrap; text-align: center;
  font-size: 0.875rem; font-weight: 500; color: var(--grey-light);
}
.trust-bar .divider { color: var(--red); }

/* ---- Challenge Grid ---- */
.challenge-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}
.challenge-card {
  background: var(--steel-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 32px;
  transition: border-color 0.3s;
}
.challenge-card:hover { border-color: rgba(200,49,43,0.4); }
.challenge-num {
  display: inline-block; font-size: 1.5rem; font-weight: 800;
  color: var(--red); margin-bottom: 16px;
}
.challenge-card h3 { margin-bottom: 12px; }
.challenge-card p { color: var(--grey-light); font-size: 0.95rem; }

/* ---- Before/After ---- */
.before-after { margin-top: 64px; text-align: center; }
.ba-pair {
  display: flex; gap: 24px; align-items: center;
  justify-content: center; flex-wrap: wrap; max-width: 800px; margin: 0 auto 24px;
}
.ba-image { position: relative; flex: 1; min-width: 280px; }
.ba-image img { border-radius: var(--radius); width: 100%; }
.ba-label {
  position: absolute; bottom: 12px; left: 12px;
  padding: 4px 12px; border-radius: 4px; font-size: 0.8rem; font-weight: 600;
}
.ba-before { background: rgba(200,49,43,0.85); color: var(--white); }
.ba-after { background: rgba(139,142,150,0.85); color: var(--steel); }
.ba-arrow { font-size: 2rem; color: var(--red); }
.ba-caption { color: var(--grey-light); max-width: 600px; margin: 0 auto; }

/* ---- Capabilities ---- */
.cap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}
.cap-card {
  background: var(--white); border-radius: var(--radius);
  overflow: hidden; box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  transition: transform 0.3s, box-shadow 0.3s;
}
.cap-card:hover { transform: translateY(-4px); box-shadow: 0 8px 24px rgba(0,0,0,0.12); }
.cap-image { height: 200px; overflow: hidden; }
.cap-image img { width: 100%; height: 100%; object-fit: cover; }
.cap-num { display: inline-block; font-size: 0.8rem; font-weight: 700; color: var(--red); margin: 20px 20px 0; }
.cap-card h3 { margin: 8px 20px 12px; }
.cap-card p { font-size: 0.9rem; color: var(--grey); margin: 0 20px 12px; }
.cap-link { display: block; margin: 0 20px 20px; font-size: 0.875rem; font-weight: 600; color: var(--red); }

/* ---- Difference ---- */
.diff-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}
.diff-card {
  background: var(--steel-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 32px;
}
.diff-icon { font-size: 1.75rem; margin-bottom: 16px; }
.diff-card h3 { margin-bottom: 12px; }
.diff-card p { color: var(--grey-light); font-size: 0.9rem; }
.metrics-bar {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
  margin-top: 48px; padding: 32px; background: var(--steel-2); border-radius: var(--radius);
  border: 1px solid var(--line);
}
.metric { text-align: center; }
.metric-value { display: block; font-size: 2.5rem; font-weight: 800; color: var(--red); line-height: 1; }
.metric-label { display: block; font-size: 0.8rem; color: var(--grey); margin-top: 8px; text-transform: uppercase; letter-spacing: 0.08em; }

/* ---- Industries ---- */
.industry-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.industry-card {
  background: var(--white); border-radius: var(--radius);
  overflow: hidden; box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  display: flex; flex-direction: column;
  transition: transform 0.3s, box-shadow 0.3s;
}
.industry-card:hover { transform: translateY(-4px); box-shadow: 0 8px 24px rgba(0,0,0,0.12); }
.industry-featured { grid-column: 1 / -1; }
.industry-featured .industry-image { height: 320px; }
.industry-featured .industry-body { padding: 32px; }
.industry-image { height: 200px; overflow: hidden; }
.industry-image img { width: 100%; height: 100%; object-fit: cover; }
.industry-body { padding: 24px; }
.industry-body h3 { margin-bottom: 8px; }
.industry-tags { font-size: 0.8rem; color: var(--red); font-weight: 500; margin-bottom: 12px; }
.industry-body p { font-size: 0.9rem; color: var(--grey); }

/* ---- Logo Wall ---- */
.logo-wall { text-align: center; }
.logo-row {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 8px 16px; margin-bottom: 16px;
}
.logo-tier1 .logo-item { font-size: 1rem; font-weight: 700; padding: 12px 24px; }
.logo-tier2 .logo-item { font-size: 0.8rem; font-weight: 500; padding: 8px 16px; }
.logo-item {
  background: var(--steel-2); border: 1px solid var(--line);
  border-radius: 6px; color: var(--grey-light);
  display: flex; align-items: center; justify-content: center;
}
.trust-note { text-align: center; margin-top: 32px; color: var(--grey); font-size: 1.05rem; max-width: 600px; margin-left: auto; margin-right: auto; }

/* ---- Results / Case Study ---- */
.results-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: start;
}
.case-study {
  background: var(--white); border-radius: var(--radius);
  overflow: hidden; box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}
.case-image img { width: 100%; height: 240px; object-fit: cover; }
.case-body { padding: 32px; }
.case-metric {
  display: inline-block; background: rgba(200,49,43,0.1); color: var(--red);
  padding: 6px 16px; border-radius: 4px; font-size: 0.9rem; font-weight: 600;
  margin-bottom: 16px;
}
.case-body h3 { margin-bottom: 16px; }
.case-body p { color: var(--grey); font-size: 0.95rem; margin-bottom: 16px; }
.case-link { color: var(--red); font-weight: 600; font-size: 0.9rem; }

.roi-panel {
  background: var(--steel); color: var(--white);
  border-radius: var(--radius); padding: 32px;
  border: 1px solid var(--line);
}
.roi-panel h3 { margin-bottom: 24px; color: var(--white); }
.roi-item {
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 0; border-bottom: 1px solid var(--line);
}
.roi-item:last-of-type { border-bottom: none; }
.roi-label { color: var(--grey-light); font-size: 0.9rem; }
.roi-value { font-weight: 700; color: var(--white); }
.roi-old { color: var(--grey); text-decoration: line-through; }
.roi-new { color: var(--red); }
.roi-footnote { color: var(--grey); font-size: 0.8rem; margin-top: 16px; }

/* ---- Reviews ---- */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.review-card {
  background: var(--steel-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 32px;
}
.review-stars { color: #f5a623; font-size: 1.1rem; margin-bottom: 16px; letter-spacing: 2px; }
.review-card p { font-size: 0.95rem; color: var(--grey-light); margin-bottom: 20px; font-style: italic; }
.review-author { font-size: 0.875rem; }
.review-author strong { color: var(--white); }
.review-author span { color: var(--grey); }
.reviews-cta { text-align: center; margin-top: 48px; }
.reviews-cta p { color: var(--grey-light); margin-bottom: 20px; font-size: 1.1rem; }

/* ---- Stakeholders ---- */
.stake-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}
.stake-card {
  background: var(--white); border-radius: var(--radius);
  padding: 32px; box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  text-align: center;
}
.stake-icon { font-size: 2rem; margin-bottom: 16px; }
.stake-card h3 { margin-bottom: 12px; }
.stake-card p { color: var(--grey); font-size: 0.9rem; }

/* ---- Knowledge Base ---- */
.kb-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.kb-card {
  background: var(--steel-2); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden;
  display: flex; flex-direction: column;
}
.kb-image { height: 220px; overflow: hidden; }
.kb-image img { width: 100%; height: 100%; object-fit: cover; }
.kb-type {
  display: inline-block; text-transform: uppercase; font-size: 0.7rem;
  font-weight: 600; letter-spacing: 0.08em; color: var(--red);
  margin: 20px 20px 0;
}
.kb-card h3 { margin: 8px 20px 20px; font-size: 1.1rem; }
.kb-download {
  margin: 0 20px 20px; color: var(--red); font-weight: 600;
  font-size: 0.875rem;
}
.kb-more { text-align: center; margin-top: 32px; }
.kb-more-link { color: var(--red); font-weight: 600; }

/* ---- Integrity ---- */
.integrity-content {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center;
}
.integrity-image img { border-radius: var(--radius); width: 100%; }
.integrity-text p { color: var(--grey); margin-bottom: 20px; font-size: 1.05rem; }
.integrity-text strong { color: var(--steel); }
.integrity-quote {
  font-size: 1.2rem; font-weight: 600; color: var(--red);
  border-left: 3px solid var(--red); padding-left: 20px; margin-top: 24px;
}

/* ---- Contact ---- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}
.contact-cta { text-align: center; }
.contact-cta .btn { display: block; margin: 0 auto 16px; max-width: 280px; }
.contact-trust { margin-top: 32px; text-align: left; max-width: 280px; margin-left: auto; margin-right: auto; }
.contact-trust p { color: var(--grey-light); font-size: 0.9rem; margin-bottom: 8px; }
.contact-form {
  background: var(--steel-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 32px;
}
.contact-form h3 { margin-bottom: 24px; color: var(--white); }
.form-row { display: flex; gap: 16px; }
.form-row .form-group { flex: 1; }
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 0.875rem; color: var(--grey-light); margin-bottom: 6px; font-weight: 500; }
.form-group .req { color: var(--red); }
.form-group input, .form-group textarea {
  width: 100%; padding: 12px 16px; border-radius: var(--radius);
  background: var(--steel); border: 1px solid var(--line);
  color: var(--white); font-family: var(--font); font-size: 0.9rem;
  transition: border-color 0.2s;
}
.form-group input:focus, .form-group textarea:focus {
  outline: none; border-color: var(--red);
}
.form-note { text-align: center; color: var(--grey); font-size: 0.8rem; margin-top: 16px; }

/* ---- Footer ---- */
#footer {
  background: var(--steel);
  border-top: 1px solid var(--line);
  padding: 64px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
}
.footer-brand h3 { font-size: 1.25rem; margin-bottom: 12px; }
.footer-brand p { color: var(--grey); font-size: 0.875rem; margin-bottom: 8px; }
.footer-tagline { font-style: italic; color: var(--grey-light) !important; }
.footer-col h4 { font-size: 0.875rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--red); margin-bottom: 16px; }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 8px; }
.footer-col a { color: var(--grey); font-size: 0.875rem; transition: color 0.2s; }
.footer-col a:hover { color: var(--white); }
.footer-contact-h { margin-top: 24px; }
.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 32px; margin-top: 48px;
  text-align: center;
}
.footer-bottom p { color: var(--grey); font-size: 0.8rem; }

/* ---- Scroll Reveal ---- */
.reveal { opacity: 0; transform: translateY(30px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ---- Responsive ---- */
@media (max-width: 768px) {
  :root { --section-pad: 64px; }
  .nav-toggle {
    display: flex; flex-direction: column; gap: 4px;
    background: none; border: none; cursor: pointer;
  }
  .nav-toggle span { width: 24px; height: 2px; background: var(--white); }
  #nav-links {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    background: var(--steel); flex-direction: column;
    padding: 24px; gap: 16px; border-bottom: 1px solid var(--line);
  }
  #nav-links.open { display: flex; }
  .hero-content { padding: 80px 24px 60px; }
  .results-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .integrity-content { grid-template-columns: 1fr; }
  .metrics-bar { grid-template-columns: repeat(2, 1fr); gap: 24px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .form-row { flex-direction: column; }
}
@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
  .metrics-bar { grid-template-columns: 1fr; }
}