/* SerBuild — Main Local CSS (Zero External CDN) */
:root {
  --color-primary: #0f172a;       /* Deep Slate Navy */
  --color-primary-light: #1e293b;
  --color-secondary: #334155;     /* Steel Slate */
  --color-accent: #d97706;        /* Engineering Amber */
  --color-accent-hover: #b45309;
  --color-accent-light: #fef3c7;
  --color-success: #16a34a;
  --color-whatsapp: #25d366;
  --color-bg: #f8fafc;
  --color-card: #ffffff;
  --color-border: #e2e8f0;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --container-max: 1280px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

  /* Theme Aliases & Surface Variables */
  --accent: var(--color-accent);
  --accent-hover: var(--color-accent-hover);
  --accent-light: var(--color-accent-light);
  --text-main: var(--color-text);
  --text-muted: var(--color-text-muted);
  --bg-surface: #0f172a;
  --bg-dark: #0b1120;
  --border-color: var(--color-border);
  --card-bg: var(--color-card);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
}
a:focus-visible, button:focus-visible, select:focus-visible, input:focus-visible, textarea:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}

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

.w-4 { width: 1rem; height: 1rem; flex-shrink: 0; }
.w-5 { width: 1.25rem; height: 1.25rem; flex-shrink: 0; }
.w-6 { width: 1.5rem; height: 1.5rem; flex-shrink: 0; }
.w-7 { width: 1.75rem; height: 1.75rem; flex-shrink: 0; }
.w-8 { width: 2rem; height: 2rem; flex-shrink: 0; }
.h-4 { height: 1rem; }
.h-5 { height: 1.25rem; }
.h-6 { height: 1.5rem; }
.h-7 { height: 1.75rem; }
.h-8 { height: 2rem; }

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  color: var(--color-primary);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

h1 { font-size: 2.5rem; margin-bottom: 1rem; }
h2 { font-size: 2rem; margin-bottom: 0.875rem; }
h3 { font-size: 1.35rem; margin-bottom: 0.75rem; }
h4 { font-size: 1.15rem; margin-bottom: 0.5rem; }

p { margin-bottom: 1rem; }
p:last-child { margin-bottom: 0; }

.lead-text {
  font-size: 1.15rem;
  color: var(--color-secondary);
  line-height: 1.7;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s ease;
  text-align: center;
}

.btn-primary {
  background-color: var(--color-accent);
  color: #ffffff;
}
.btn-primary:hover {
  background-color: var(--color-accent-hover);
  color: #ffffff;
}

.btn-secondary {
  background-color: var(--color-primary);
  color: #ffffff;
}
.btn-secondary:hover {
  background-color: var(--color-primary-light);
  color: #ffffff;
}

.btn-outline {
  background-color: transparent;
  border-color: var(--color-border);
  color: var(--color-primary);
}
.btn-outline:hover {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: #ffffff;
}

.btn-outline-white,
.btn-outline-light {
  background-color: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.35);
  color: #ffffff;
  backdrop-filter: blur(4px);
}
.btn-outline-white:hover,
.btn-outline-light:hover {
  background-color: #ffffff;
  border-color: #ffffff;
  color: var(--color-primary);
}

.btn-whatsapp {
  background-color: var(--color-whatsapp);
  color: #ffffff;
  font-weight: 600;
}
.btn-whatsapp:hover {
  background-color: #1eb856;
}

.btn-lg {
  padding: 0.95rem 2rem;
  font-size: 1.05rem;
}

/* Header & Navbar */
.site-header {
  background-color: var(--color-primary);
  color: #ffffff;
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: var(--shadow-md);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.site-header .container {
  max-width: 1440px;
  padding-left: 1.25rem;
  padding-right: 1.25rem;
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 0.75rem;
  white-space: nowrap;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: #ffffff;
  flex-shrink: 0;
}
.nav-brand span.tagline {
  font-size: 0.75rem;
  font-weight: 400;
  color: #94a3b8;
  display: block;
  letter-spacing: 0;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  list-style: none;
  margin: 0;
  padding: 0;
  flex-wrap: nowrap;
}

.nav-link {
  font-size: 0.875rem;
  font-weight: 500;
  color: #cbd5e1;
  padding: 0.4rem 0.55rem;
  position: relative;
  white-space: nowrap;
  border-radius: var(--radius-sm);
  transition: color 0.15s ease, background-color 0.15s ease;
}
.nav-link:hover, .nav-link.active {
  color: #ffffff;
  background-color: rgba(255, 255, 255, 0.06);
}
.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0.55rem;
  right: 0.55rem;
  height: 2px;
  background-color: var(--color-accent);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
  white-space: nowrap;
}

.lang-selector {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: #94a3b8;
  background: rgba(255, 255, 255, 0.08);
  padding: 0.35rem 0.55rem;
  border-radius: var(--radius-sm);
  white-space: nowrap;
}
.lang-selector a {
  color: #cbd5e1;
}
.lang-selector a:hover, .lang-selector a.active {
  color: var(--color-accent);
}

.nav-actions .btn-primary {
  padding: 0.45rem 1rem;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

/* Mobile Off-Canvas Menu */
.hamburger-btn {
  display: none;
  background: transparent;
  border: none;
  color: #ffffff;
  cursor: pointer;
  padding: 0.5rem;
}

.offcanvas-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: rgba(15, 23, 42, 0.7);
  z-index: 98;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.offcanvas-overlay.active {
  display: block;
  opacity: 1;
}

.offcanvas-panel {
  position: fixed;
  top: 0;
  right: 0;
  width: 80%;
  max-width: 320px;
  height: 100vh;
  background-color: var(--color-primary);
  color: #ffffff;
  z-index: 99;
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  box-shadow: -4px 0 20px rgba(0, 0, 0, 0.3);
}
.offcanvas-panel.active {
  transform: translateX(0);
}

.offcanvas-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 2rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding-bottom: 1rem;
}

.offcanvas-close {
  background: transparent;
  border: none;
  color: #ffffff;
  cursor: pointer;
  padding: 0.5rem;
}

.offcanvas-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
.offcanvas-nav a {
  display: block;
  font-size: 1.05rem;
  font-weight: 500;
  color: #cbd5e1;
  padding: 0.5rem 0;
}
.offcanvas-nav a:hover {
  color: var(--color-accent);
}

/* Breadcrumb Navigation */
.breadcrumb-wrapper {
  background-color: #f1f5f9;
  border-bottom: 1px solid var(--color-border);
  padding: 0.75rem 0;
  font-size: 0.875rem;
}
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  list-style: none;
  color: var(--color-text-muted);
}
.breadcrumb-list a:hover {
  color: var(--color-accent);
}
.breadcrumb-separator {
  color: #94a3b8;
}

/* Hero Section */
.hero-section {
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  color: #ffffff;
  padding: 4.5rem 0 4rem;
  position: relative;
  overflow: hidden;
}

/* Homepage Hero with AI-Generated High-End Background Image */
.hero-section.hero-home {
  background-color: #0b1120;
  background-image: 
    linear-gradient(135deg, rgba(11, 17, 32, 0.94) 0%, rgba(15, 23, 42, 0.85) 45%, rgba(15, 23, 42, 0.72) 100%),
    url('../images/hero-bg.jpg');
  background-size: cover;
  background-position: center right;
  background-repeat: no-repeat;
  padding: 6rem 0 5rem;
}

.hero-section.hero-home::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 80% 30%, rgba(217, 119, 6, 0.15) 0%, rgba(15, 23, 42, 0) 60%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 840px;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background-color: rgba(217, 119, 6, 0.15);
  border: 1px solid rgba(217, 119, 6, 0.4);
  color: #fde68a;
  padding: 0.35rem 0.85rem;
  border-radius: 9999px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  backdrop-filter: blur(4px);
}
.hero-title {
  color: #ffffff;
  font-size: 3rem;
  line-height: 1.15;
  margin-bottom: 1.25rem;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.4);
}
.hero-subtitle {
  font-size: 1.2rem;
  color: #cbd5e1;
  line-height: 1.7;
  margin-bottom: 2rem;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
}
.hero-section .btn-outline,
.hero-actions .btn-outline {
  background-color: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.35);
  color: #ffffff;
  backdrop-filter: blur(4px);
}
.hero-section .btn-outline:hover,
.hero-actions .btn-outline:hover {
  background-color: #ffffff;
  border-color: #ffffff;
  color: var(--color-primary);
}

/* Trust Bar */
.trust-bar {
  background-color: #0b1120;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding: 1rem 0;
  color: #94a3b8;
  font-size: 0.875rem;
  font-weight: 500;
}
.trust-bar-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.trust-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Grids & Cards */
.section {
  padding: 4.5rem 0;
}
.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 3rem;
}
.section-subtitle {
  color: var(--color-text-muted);
  font-size: 1.1rem;
}

.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 2rem; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; }

.card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: #cbd5e1;
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background-color: var(--color-accent-light);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.25rem;
}

.card-title {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}
.card-desc {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

/* Quick Info Table */
.quick-info-box {
  background-color: #f1f5f9;
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin: 2rem 0;
}
.quick-info-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}
.quick-info-table th, .quick-info-table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid #e2e8f0;
  font-size: 0.95rem;
}
.quick-info-table th {
  background-color: #e2e8f0;
  color: var(--color-primary);
  font-weight: 600;
  width: 30%;
}

/* FAQ Accordion */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 900px;
  margin: 0 auto;
}
.faq-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.faq-question {
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  padding: 1.25rem 1.5rem;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.faq-icon {
  transition: transform 0.3s ease;
}
.faq-item.active .faq-icon {
  transform: rotate(180deg);
}
.faq-answer {
  display: none;
  padding: 0 1.5rem 1.25rem;
  color: var(--color-secondary);
  line-height: 1.7;
}
.faq-item.active .faq-answer {
  display: block;
}

/* Multi-Step RFQ Form Engine */
.rfq-container {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-xl);
  max-width: 900px;
  margin: 0 auto;
}
.rfq-progress {
  display: flex;
  justify-content: space-between;
  position: relative;
  margin-bottom: 2.5rem;
}
.rfq-progress::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-border);
  z-index: 1;
  transform: translateY(-50%);
}
.rfq-step-indicator {
  position: relative;
  z-index: 2;
  background-color: var(--color-card);
  border: 2px solid var(--color-border);
  color: var(--color-text-muted);
  width: 38px;
  height: 38px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  transition: all 0.3s ease;
  cursor: pointer;
}
.rfq-step-indicator:hover {
  transform: scale(1.08);
  border-color: var(--color-accent);
}
.rfq-step-indicator.active {
  border-color: var(--color-accent);
  background-color: var(--color-accent);
  color: #ffffff;
}
.rfq-step-indicator.completed {
  border-color: var(--color-success);
  background-color: var(--color-success);
  color: #ffffff;
}

.rfq-step {
  display: none;
}
.rfq-step.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

.form-group {
  margin-bottom: 1.5rem;
}
.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-primary);
  font-size: 0.95rem;
}
.form-control {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-family: inherit;
  color: var(--color-text);
  background-color: #ffffff;
}
.form-control:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(217, 119, 6, 0.15);
}

.selection-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}
.selection-card {
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  cursor: pointer;
  transition: all 0.2s ease;
  text-align: center;
}
.selection-card:hover {
  border-color: #94a3b8;
  background-color: #f8fafc;
}
.selection-card.selected {
  border-color: var(--color-accent);
  background-color: var(--color-accent-light);
}

/* Fixed Utility Buttons */
.scroll-top-btn {
  position: fixed;
  bottom: 24px;
  left: 20px;
  z-index: 40;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background-color: var(--color-primary);
  color: #ffffff;
  border: none;
  box-shadow: var(--shadow-lg);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all 0.3s ease;
}
.scroll-top-btn.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.scroll-top-btn:hover {
  background-color: var(--color-accent);
}

.fixed-whatsapp-btn {
  position: fixed;
  bottom: 24px;
  right: 20px;
  z-index: 40;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background-color: var(--color-whatsapp);
  color: #ffffff;
  box-shadow: var(--shadow-xl);
  display: flex;
  align-items: center;
  justify-content: center;
  animation: pulseWhatsapp 2s infinite;
  transition: transform 0.2s ease;
}
.fixed-whatsapp-btn:hover {
  transform: scale(1.08);
}
.fixed-whatsapp-btn .tooltip {
  position: absolute;
  right: 70px;
  background-color: var(--color-primary);
  color: #ffffff;
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 500;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
  box-shadow: var(--shadow-md);
}
.fixed-whatsapp-btn:hover .tooltip {
  opacity: 1;
}

@keyframes pulseWhatsapp {
  0% { box-shadow: 0 0 0 0 rgba(37, 211, 102, 0.6); }
  70% { box-shadow: 0 0 0 14px rgba(37, 211, 102, 0); }
  100% { box-shadow: 0 0 0 0 rgba(37, 211, 102, 0); }
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Footer */
.site-footer {
  background-color: #0b1120;
  color: #94a3b8;
  padding: 4.5rem 0 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.9rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 3rem;
  margin-bottom: 3rem;
}
.footer-title {
  color: #ffffff;
  font-size: 1.05rem;
  margin-bottom: 1.25rem;
}
.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}
.footer-links a:hover {
  color: var(--color-accent);
}
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 2rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.85rem;
}

/* Responsive Media Queries */
@media (max-width: 1160px) {
  .nav-menu { display: none; }
  .hamburger-btn { display: block; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  h1 { font-size: 2.1rem; }
  h2 { font-size: 1.7rem; }
  .hero-title { font-size: 2.2rem; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .rfq-container { padding: 1.5rem; }
  .rfq-progress { margin-bottom: 1.5rem; }
}