/* ═══════════════════════════════════════════════════════════
   BrightWelding — Premium Industrial B2B
   Font: Source Sans 3 (body) + Lexend (headings)
   Icons: Font Awesome 6 Free
   Architecture: 8px radius cards · 6px buttons · backdrop-blur nav
   ═══════════════════════════════════════════════════════════ */

:root {
  --primary: #1A3C6E; --primary-light: #2A5A9E; --primary-dark: #0F2440;
  --accent: #F97316; --accent-hover: #EA580C;
  --ink: #1E293B; --body: #334155; --muted: #64748B; --muted-soft: #94A3B8;
  --canvas: #FFFFFF; --surface-soft: #F8FAFC; --surface-card: #F1F5F9; --surface-strong: #E2E8F0;
  --surface-dark: #0F2440; --surface-dark-elevated: #1A3C6E;
  --on-primary: #FFFFFF; --on-dark: #FFFFFF; --on-dark-soft: #CBD5E1;
  --hairline: #E2E8F0; --hairline-strong: #CBD5E1;
  --success: #10B981; --warning: #F59E0B; --error: #EF4444;

  --font: 'Source Sans 3', system-ui, sans-serif;
  --font-heading: 'Lexend', system-ui, sans-serif;
  --sp-xxs:4px; --sp-xs:8px; --sp-sm:12px; --sp-md:16px; --sp-lg:24px; --sp-xl:32px; --sp-xxl:48px; --sp-xxxl:64px; --sp-section:80px;
  --radius-xs:4px; --radius-sm:6px; --radius-md:8px; --radius-lg:12px; --radius-pill:9999px;
  --shadow-xs:0 1px 3px rgba(15,36,64,0.04); --shadow-sm:0 2px 8px rgba(15,36,64,0.06);
  --shadow-md:0 4px 16px rgba(15,36,64,0.08); --shadow-card-hover:0 8px 30px rgba(15,36,64,0.10);
  --shadow-btn:0 4px 12px rgba(26,60,110,0.25); --shadow-btn-accent:0 4px 16px rgba(249,115,22,0.30);
  --container-max:1280px; --nav-height:64px;
  --ease: cubic-bezier(0.32, 0.72, 0, 1);
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:16px;scroll-behavior:smooth}
body{font-family:var(--font);font-weight:400;line-height:1.7;color:var(--body);background:var(--canvas);overflow-x:hidden}
h1,h2,h3,h4{font-family:var(--font-heading);color:var(--ink);letter-spacing:-0.02em}
h1{font-size:clamp(2.25rem,5vw,3.25rem);font-weight:700;line-height:1.1}
h2{font-size:clamp(1.75rem,3.5vw,2.25rem);font-weight:700;line-height:1.2}
h3{font-size:1.25rem;font-weight:600;line-height:1.3}
a{color:var(--primary);text-decoration:none;transition:color 150ms var(--ease)}
a:hover{color:var(--primary-light)}
.container{width:100%;max-width:var(--container-max);margin:0 auto;padding:0 var(--sp-lg)}

/* ── Navigation ────────────────────────────────────── */
.site-nav{position:fixed;top:0;left:0;right:0;z-index:1000;height:var(--nav-height);background:rgba(255,255,255,0.85);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border-bottom:1px solid rgba(226,232,240,0.3);display:flex;align-items:center;transition:background 400ms var(--ease),backdrop-filter 400ms var(--ease),border-color 400ms var(--ease)}
.site-nav.scrolled{background:rgba(255,255,255,0.95);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border-bottom:1px solid rgba(226,232,240,0.6);box-shadow:0 1px 3px rgba(0,0,0,0.04)}
.site-nav .container{display:flex;align-items:center;justify-content:space-between}
.nav-logo{display:flex;align-items:center;gap:var(--sp-sm);font-weight:700;font-size:1.0625rem;color:var(--ink);text-decoration:none;white-space:nowrap;letter-spacing:-0.02em}
.nav-logo svg{height:32px;width:auto}
.nav-links{display:flex;align-items:center;gap:var(--sp-xl);list-style:none}
.nav-links a{font-size:0.875rem;font-weight:500;color:var(--body);padding:var(--sp-xs) 0;position:relative}
.nav-links a:hover,.nav-links a.active{color:var(--primary)}
.nav-links a.active::after{content:'';position:absolute;bottom:0;left:0;right:0;height:2px;background:var(--primary)}
.nav-dropdown{position:relative}
.nav-dropdown-menu{display:none;position:absolute;top:100%;left:0;background:var(--canvas);border:1px solid var(--hairline);min-width:280px;padding:var(--sp-md);list-style:none;box-shadow:var(--shadow-md)}
.nav-dropdown:hover .nav-dropdown-menu{display:block}
.nav-dropdown-menu li{margin-bottom:var(--sp-xs)}
.nav-dropdown-menu a{display:flex;align-items:center;gap:var(--sp-sm);padding:var(--sp-sm) var(--sp-md);font-size:0.875rem}
.nav-dropdown-menu a:hover{background:var(--surface-soft)}
.nav-right{display:flex;align-items:center;gap:var(--sp-md)}
.nav-lang{font-size:0.875rem;color:var(--muted);text-decoration:none;display:flex;align-items:center;gap:var(--sp-xxs)}
.nav-rfq-btn{background:var(--accent);color:#FFFFFF!important;padding:8px 16px;font-size:0.875rem;font-weight:600;text-decoration:none;border-radius:var(--radius-md);transition:background 150ms var(--ease)}
.nav-rfq-btn:hover{background:var(--accent-hover)}
.nav-hamburger{display:none;flex-direction:column;gap:5px;cursor:pointer;background:none;border:none;padding:var(--sp-xs)}
.nav-hamburger span{display:block;width:22px;height:2px;background:var(--ink);transition:all 200ms var(--ease)}

/* ── Buttons ────────────────────────────────────────── */
.btn{display:inline-flex;align-items:center;gap:var(--sp-sm);font-family:var(--font-heading);font-size:0.875rem;font-weight:600;letter-spacing:0.3px;padding:14px 32px;height:48px;text-decoration:none;border:none;border-radius:var(--radius-sm);cursor:pointer;transition:all 150ms var(--ease)}
.btn-primary{background:var(--primary);color:var(--on-primary)}
.btn-primary:hover{background:var(--primary-light);color:var(--on-primary);transform:translateY(-1px);box-shadow:var(--shadow-btn)}
.btn-primary:active{transform:scale(0.98)}
.btn-accent{background:var(--accent);color:var(--on-primary)}
.btn-accent:hover{background:var(--accent-hover);color:var(--on-primary);transform:translateY(-1px);box-shadow:var(--shadow-btn-accent)}
.btn-accent:active{transform:scale(0.98)}
.btn-secondary{background:transparent;color:var(--ink);border:1px solid var(--hairline-strong)}
.btn-secondary:hover{border-color:var(--ink);color:var(--ink)}
.btn-dark{background:transparent;color:var(--on-dark);border:1px solid var(--on-dark-soft)}
.btn-dark:hover{border-color:var(--on-dark);color:var(--on-dark)}
.btn-text{background:transparent;color:var(--primary);font-size:0.75rem;font-weight:700;letter-spacing:1.2px;text-transform:uppercase;padding:0;height:auto}

/* ── Section Rhythm ─────────────────────────────────── */
.section{padding:var(--sp-section) 0}
.section-soft{background:var(--surface-soft);padding:var(--sp-section) 0}
.section-dark{background:var(--surface-dark);color:var(--on-dark);padding:var(--sp-section) 0}
.section-dark h2,.section-dark h3{color:var(--on-dark)}
.section-dark p{color:var(--on-dark-soft)}
.section-label{display:flex;align-items:center;gap:var(--sp-sm);color:var(--accent);font-family:var(--font);font-size:0.75rem;font-weight:700;letter-spacing:1.2px;text-transform:uppercase;margin-bottom:var(--sp-md)}
.section-label::before{content:'';display:block;width:40px;height:2px;background:var(--accent)}
.section-label-center{justify-content:center;text-align:center}
.section-label-center::before{display:none}
.section-label-center::after{content:'';display:block;width:40px;height:2px;background:var(--accent)}

/* ── Hero ───────────────────────────────────────────── */
.hero-home{position:relative;min-height:100vh;display:flex;align-items:center;background:var(--surface-dark);overflow:hidden}
.hero-bg{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:0.4;filter:saturate(0.3) brightness(0.6)}
.hero-overlay{position:absolute;inset:0;background:linear-gradient(to right,rgba(15,36,64,0.95) 0%,rgba(15,36,64,0.65) 55%,rgba(15,36,64,0.2) 100%);z-index:1}
.hero-content{position:relative;z-index:2;max-width:640px;padding-top:var(--nav-height)}
.hero-content h1{color:#FFFFFF;margin-bottom:var(--sp-lg)}
.hero-content .body-lg{color:rgba(255,255,255,0.6);font-size:1.125rem;font-weight:300;line-height:1.7;margin-bottom:var(--sp-xl)}
.hero-cta-group{display:flex;gap:var(--sp-md);flex-wrap:wrap}
.hero-page{background:var(--surface-dark);color:#FFFFFF;padding:80px 0;text-align:center}
.hero-page h1{color:#FFFFFF}
.hero-page .breadcrumb{display:flex;justify-content:center;gap:var(--sp-xs);margin-top:var(--sp-md);font-size:0.875rem;color:rgba(255,255,255,0.45)}
.hero-page .breadcrumb a{color:rgba(255,255,255,0.45)}
.hero-page .breadcrumb a:hover{color:#FFFFFF}

/* ── Trust Bar ──────────────────────────────────────── */
.trust-bar{padding:var(--sp-lg) 0;background:var(--canvas);border-bottom:1px solid var(--hairline)}
.trust-bar-grid{display:flex;justify-content:center;align-items:center;gap:var(--sp-xxl);flex-wrap:wrap}
.trust-bar-item{display:flex;align-items:center;gap:var(--sp-sm);font-size:0.875rem;color:var(--body);font-weight:500}

/* ── Product Cards ──────────────────────────────────── */
.product-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--sp-lg)}
.product-card{background:var(--canvas);border:1px solid var(--hairline);border-radius:var(--radius-md);transition:transform 200ms var(--ease),box-shadow 200ms var(--ease)}
.product-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-card-hover)}
.product-card-photo{background:var(--surface-card);aspect-ratio:16/10;display:flex;align-items:center;justify-content:center;padding:var(--sp-lg);border-bottom:1px solid var(--hairline)}
.product-card-photo img{max-width:100%;max-height:100%;object-fit:contain}
.product-card-body{padding:var(--sp-lg)}
.product-card-body h4{font-size:1.0625rem;font-weight:600;margin-bottom:var(--sp-xs)}
.product-card-specs{display:flex;gap:var(--sp-md);margin-bottom:var(--sp-md);color:var(--muted);font-size:0.75rem}
.product-card-link{color:var(--primary);font-size:0.875rem;font-weight:600;display:inline-flex;align-items:center;gap:var(--sp-xxs)}

/* ── Tag / Chip ─────────────────────────────────────── */
.tag{display:inline-block;font-size:0.6875rem;font-weight:600;letter-spacing:0.8px;text-transform:uppercase;padding:4px 12px;border-radius:var(--radius-pill);background:var(--surface-soft);color:var(--muted);border:1px solid var(--hairline)}

/* ── Certification Badges ───────────────────────────── */
.cert-strip{display:flex;justify-content:center;gap:var(--sp-lg);flex-wrap:wrap}
.cert-badge{background:var(--canvas);border:1px solid var(--hairline);border-radius:var(--radius-md);padding:16px 24px;display:flex;align-items:center;gap:var(--sp-sm);font-size:0.8125rem;font-weight:600;letter-spacing:0.5px;text-transform:uppercase}
.cert-badge i{color:var(--primary);font-size:1.5rem}

/* ── Trust Stats ────────────────────────────────────── */
.trust-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--sp-xl);text-align:center}
.trust-stat-value{font-family:var(--font);font-size:2.25rem;font-weight:700;color:var(--primary);line-height:1.1}
.trust-stat-label{display:block;font-size:0.6875rem;font-weight:700;text-transform:uppercase;letter-spacing:1.2px;color:var(--muted);margin-top:var(--sp-xs)}

/* ── Industry Cards ─────────────────────────────────── */
.industry-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--sp-lg)}
.industry-card{position:relative;aspect-ratio:4/3;overflow:hidden;display:flex;align-items:flex-end;transition:transform 300ms var(--ease)}
.industry-card:hover{transform:scale(1.03)}
.industry-card img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;transition:transform 500ms var(--ease)}
.industry-card:hover img{transform:scale(1.06)}
.industry-card-overlay{position:absolute;inset:0;background:linear-gradient(to top,rgba(15,36,64,0.85) 0%,rgba(15,36,64,0.3) 100%)}
.industry-card-content{position:relative;z-index:1;padding:var(--sp-xl);color:var(--on-dark)}
.industry-card-content h4{color:var(--on-dark);margin-bottom:var(--sp-xs)}
.industry-card-content p{color:var(--on-dark-soft);font-size:0.875rem;margin-bottom:var(--sp-md)}

/* ── Case Study Cards ───────────────────────────────── */
.case-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--sp-lg)}
.case-card{background:var(--canvas);border:1px solid var(--hairline);border-radius:var(--radius-md);overflow:hidden;transition:transform 200ms var(--ease),box-shadow 200ms var(--ease)}
.case-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-card-hover)}
.case-card img{width:100%;aspect-ratio:16/9;object-fit:cover;border-bottom:1px solid var(--hairline)}
.case-card-body{padding:var(--sp-lg)}
.case-card-industry{font-size:0.6875rem;font-weight:600;text-transform:uppercase;letter-spacing:0.8px;color:var(--primary);margin-bottom:var(--sp-xs)}
.case-card-body h4{font-size:1.0625rem;margin-bottom:var(--sp-sm)}
.case-card-result{font-weight:600;font-size:0.875rem;color:var(--primary);margin-top:var(--sp-md)}

/* ── Blog / News Cards ──────────────────────────────── */
.blog-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--sp-lg)}
.blog-card{background:var(--canvas);border:1px solid var(--hairline);border-radius:var(--radius-md);overflow:hidden;transition:transform 200ms var(--ease),box-shadow 200ms var(--ease)}
.blog-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-card-hover)}
.blog-card img{width:100%;aspect-ratio:16/9;object-fit:cover;border-bottom:1px solid var(--hairline)}
.blog-card-body{padding:var(--sp-lg)}
.blog-card-tag{font-size:0.6875rem;font-weight:700;text-transform:uppercase;letter-spacing:0.12em;color:var(--primary);margin-bottom:var(--sp-xs)}
.blog-card-body h4{font-size:1rem;font-weight:600;margin-bottom:var(--sp-xs)}
.blog-card-date{font-size:0.75rem;color:var(--muted-soft)}

/* ── Video Embed ────────────────────────────────────── */
.video-wrap{position:relative;aspect-ratio:16/9;background:var(--surface-dark);display:flex;align-items:center;justify-content:center;cursor:pointer}
.video-wrap img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.video-play-btn{position:relative;z-index:1;color:#FFFFFF;font-size:4rem;opacity:0.85;transition:opacity 150ms,transform 150ms}
.video-wrap:hover .video-play-btn{opacity:1;transform:scale(1.1)}

/* ── FAQ Accordion ──────────────────────────────────── */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{border:1px solid var(--hairline);border-radius:var(--radius-md);margin-bottom:var(--sp-xs);overflow:hidden;background:var(--canvas)}
.faq-q{width:100%;background:none;border:none;padding:var(--sp-lg);font-family:var(--font);font-size:1rem;font-weight:600;color:var(--ink);text-align:left;cursor:pointer;display:flex;justify-content:space-between;align-items:center}
.faq-q:hover{background:var(--surface-soft)}
.faq-q i{transition:transform 200ms var(--ease);color:var(--muted)}
.faq-q[aria-expanded="true"] i{transform:rotate(180deg)}
.faq-a{display:none;padding:0 var(--sp-lg) var(--sp-lg);line-height:1.7}
.faq-item.open .faq-a{display:block}

/* ── RFQ Form ───────────────────────────────────────── */
.rfq-section{background:var(--surface-soft);border:1px solid var(--hairline);border-radius:var(--radius-md);padding:var(--sp-xl)}
.rfq-grid{display:grid;grid-template-columns:3fr 2fr;gap:var(--sp-xl);max-width:900px;margin:0 auto}
.form-group{margin-bottom:var(--sp-md)}
.form-group label{display:block;font-size:0.8125rem;font-weight:600;margin-bottom:6px;color:var(--body-strong)}
.form-input,.form-select,.form-textarea{width:100%;background:var(--canvas);border:1px solid var(--hairline);border-radius:var(--radius-md);font-family:var(--font);font-size:1rem;font-weight:300;padding:12px 16px;height:48px;color:var(--ink);transition:border-color 150ms,box-shadow 150ms}
.form-textarea{height:120px;resize:vertical}
.form-input:focus,.form-select:focus,.form-textarea:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px rgba(26,60,110,0.10)}
.rfq-trust{display:flex;flex-direction:column;gap:var(--sp-md);justify-content:center}
.rfq-trust-promise{display:flex;align-items:center;gap:var(--sp-sm);font-size:0.875rem;color:var(--body)}

/* ── Download Cards ─────────────────────────────────── */
.download-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--sp-md);max-width:800px}
.download-card{display:flex;align-items:center;gap:var(--sp-md);background:var(--canvas);border:1px solid var(--hairline);border-radius:var(--radius-md);padding:var(--sp-md);transition:transform 150ms,box-shadow 150ms}
.download-card:hover{transform:translateY(-2px);box-shadow:var(--shadow-sm)}
.download-card i{color:var(--accent);font-size:2rem}

/* ── CTA Band ───────────────────────────────────────── */
.cta-band{background:var(--surface-dark);text-align:center;padding:var(--sp-section) 0}
.cta-band h2{color:#FFFFFF;margin-bottom:var(--sp-md)}
.cta-band .body-lg{color:var(--on-dark-soft);max-width:560px;margin:0 auto var(--sp-xl);font-size:1.125rem;font-weight:300}

/* ── Footer ─────────────────────────────────────────── */
.site-footer{background:var(--surface-dark);color:var(--on-dark-soft);padding:var(--sp-xxxl) 0;font-size:0.875rem;font-weight:300}
.footer-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--sp-xl);margin-bottom:var(--sp-xxl)}
.footer-col h4{color:var(--on-dark);font-size:0.8125rem;font-weight:600;margin-bottom:var(--sp-md);letter-spacing:0.5px}
.footer-col ul{list-style:none}
.footer-col li{margin-bottom:var(--sp-xs)}
.footer-col a{color:var(--on-dark-soft);font-size:0.875rem;font-weight:300;transition:color 150ms}
.footer-col a:hover{color:var(--on-dark)}
.footer-social{display:flex;gap:var(--sp-md);margin-top:var(--sp-lg)}
.footer-social a{color:var(--on-dark-soft);font-size:1.25rem;transition:color 150ms}
.footer-social a:hover{color:var(--on-dark)}
.footer-bottom{border-top:1px solid var(--surface-dark-elevated);padding-top:var(--sp-lg);font-size:0.75rem;color:var(--muted-soft);display:flex;justify-content:space-between;flex-wrap:wrap;gap:var(--sp-md)}

/* ── Skip / Focus / Utility ─────────────────────────── */
.skip-link{position:absolute;top:-100px;left:var(--sp-md);background:var(--primary);color:#FFFFFF;padding:var(--sp-sm) var(--sp-md);z-index:9999}
.skip-link:focus{top:var(--sp-xs)}
:focus-visible{outline:2px solid var(--primary);outline-offset:2px}
.text-center{text-align:center}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.mb-sm{margin-bottom:var(--sp-sm)}.mb-md{margin-bottom:var(--sp-md)}.mb-lg{margin-bottom:var(--sp-lg)}.mb-xl{margin-bottom:var(--sp-xl)}
.mt-lg{margin-top:var(--sp-lg)}

/* ── Responsive ─────────────────────────────────────── */
@media(max-width:1023px){
  .product-grid{grid-template-columns:repeat(2,1fr)}
  .industry-grid{grid-template-columns:repeat(2,1fr)}
  .blog-grid{grid-template-columns:repeat(2,1fr)}
  .case-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:repeat(2,1fr)}
  .trust-stats{grid-template-columns:repeat(4,1fr);gap:var(--sp-md)}
  .rfq-grid{grid-template-columns:1fr}
}
@media(max-width:767px){
  :root{--sp-section:56px}
  .nav-links,.nav-right .nav-rfq-btn{display:none}
  .nav-hamburger{display:flex}
  .product-grid{grid-template-columns:1fr}
  .industry-grid{grid-template-columns:1fr}
  .blog-grid{grid-template-columns:1fr}
  .case-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .trust-stats{grid-template-columns:repeat(2,1fr)}
  .download-grid{grid-template-columns:1fr}
  .hero-home{min-height:80vh}
  .hero-content{text-align:center}
  .hero-cta-group{justify-content:center}
}
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:0.01ms!important;transition-duration:0.01ms!important}
  html{scroll-behavior:auto}
}

.model-list h4{font-size:1rem;margin-bottom:var(--sp-sm)}.model-list li a{display:inline-block;padding:6px 14px;border:1px solid var(--hairline);border-radius:var(--radius-sm);font-size:.8125rem;font-weight:500;transition:all 150ms var(--ease)}.model-list li a:hover{border-color:var(--primary);color:var(--primary);background:var(--surface-soft)}