/**
 * RSTRUCT Home Page - SEO-friendly PHP version
 * Design tokens match React app (engineering-blue palette)
 */

:root {
  --engineering-blue-50: #f0f9ff;
  --engineering-blue-100: #e0f2fe;
  --engineering-blue-200: #bae6fd;
  --engineering-blue-300: #7dd3fc;
  --engineering-blue-400: #38bdf8;
  --engineering-blue-500: #0ea5e9;
  --engineering-blue-600: #0284c7;
  --engineering-blue-700: #0369a1;
  --gray-50: #f9fafb;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-900: #111827;
  --radius: 0.5rem;
  --container-max: 1400px;
  --font-sans: 'Inter', system-ui, sans-serif;
}

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

html {
  line-height: 1.5;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--gray-900);
  background: #fff;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  z-index: 100;
  padding: 0.5rem 1rem;
  background: var(--engineering-blue-600);
  color: #fff;
  border-radius: var(--radius);
  text-decoration: none;
  font-weight: 600;
  transition: top 0.2s;
}
.skip-link:focus {
  top: 1rem;
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1rem;
  padding-right: 1rem;
}

/* Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(4px);
  border-bottom: 1px solid var(--gray-200);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  padding-bottom: 1rem;
}

.logo a {
  display: block;
}
.logo img {
  height: 3.75rem;
  width: auto;
  display: block;
}

.menu-toggle {
  display: block;
  width: 2.5rem;
  height: 2.5rem;
  padding: 0;
  border: none;
  background: transparent;
  cursor: pointer;
  position: relative;
}
.menu-toggle::before,
.menu-toggle::after {
  content: '';
  position: absolute;
  left: 0.5rem;
  right: 0.5rem;
  height: 2px;
  background: var(--gray-700);
  transition: transform 0.2s;
}
.menu-toggle::before { top: 0.6rem; }
.menu-toggle::after { top: 1.1rem; }
.menu-toggle[aria-expanded="true"]::before {
  transform: translateY(0.25rem) rotate(45deg);
}
.menu-toggle[aria-expanded="true"]::after {
  transform: translateY(-0.25rem) rotate(-45deg);
}

.main-nav {
  display: none;
}
.main-nav.is-open {
  display: block;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: #fff;
  border-bottom: 1px solid var(--gray-200);
  padding: 1rem;
}

.nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-item a,
.nav-item .nav-label {
  display: block;
  padding: 0.5rem 0.75rem;
  color: var(--gray-700);
  text-decoration: none;
  font-weight: 500;
}
.nav-item a:hover,
.nav-item .nav-label {
  color: var(--engineering-blue-600);
}

.nav-item.has-dropdown .dropdown {
  list-style: none;
  margin: 0;
  padding-left: 1rem;
  padding-bottom: 0.5rem;
}
.nav-item.has-dropdown .dropdown a {
  font-size: 0.875rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 1.5rem;
  font-weight: 600;
  font-family: inherit;
  font-size: 1rem;
  border-radius: var(--radius);
  cursor: pointer;
  text-decoration: none;
  border: 2px solid transparent;
  transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}
.btn-primary {
  background: var(--engineering-blue-600);
  color: #fff;
}
.btn-primary:hover {
  background: var(--engineering-blue-700);
}
.btn-outline {
  border-color: var(--engineering-blue-600);
  color: var(--engineering-blue-600);
  background: transparent;
}
.btn-outline:hover {
  background: var(--engineering-blue-600);
  color: #fff;
}
.btn-lg { padding: 1rem 2rem; font-size: 1.125rem; }
.btn-block { width: 100%; }

/* Hero */
.hero {
  position: relative;
  background: linear-gradient(to bottom right, var(--engineering-blue-50), #fff, var(--engineering-blue-50));
  padding-top: 6rem;
  padding-bottom: 4rem;
  overflow: hidden;
}

.hero-pattern {
  position: absolute;
  inset: 0;
  opacity: 0.05;
  pointer-events: none;
}
.hero-pattern::before,
.hero-pattern::after {
  content: '';
  position: absolute;
  border: 1px solid var(--engineering-blue-300);
}
.hero-pattern::before {
  top: 2.5rem;
  left: 2.5rem;
  width: 8rem;
  height: 8rem;
  transform: rotate(45deg);
}
.hero-pattern::after {
  top: 10rem;
  right: 5rem;
  width: 6rem;
  height: 6rem;
  transform: rotate(12deg);
}

.hero-inner { position: relative; z-index: 1; }

.hero-grid {
  display: grid;
  gap: 3rem;
  align-items: center;
}

.hero-title {
  font-size: 2.25rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--gray-900);
  margin: 0 0 1.5rem;
}
.hero-title .accent { color: var(--engineering-blue-600); }

.hero-lead {
  font-size: 1.25rem;
  color: var(--gray-600);
  line-height: 1.6;
  margin: 0 0 2rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2rem;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--gray-200);
  margin: 0;
}
.stat { text-align: center; }
.stat-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--engineering-blue-600);
  margin: 0;
}
.stat-label {
  font-size: 0.875rem;
  color: var(--gray-600);
  margin: 0.25rem 0 0;
}

.hero-media {
  position: relative;
}
.hero-media img {
  width: 100%;
  height: 24rem;
  object-fit: cover;
  border-radius: 1rem;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

/* Sections common */
.section-header {
  text-align: center;
  margin-bottom: 4rem;
}
.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--gray-900);
  margin: 0 0 1rem;
}
.section-title .accent { color: var(--engineering-blue-600); }
.section-lead {
  font-size: 1.25rem;
  color: var(--gray-600);
  max-width: 48rem;
  margin: 0 auto;
  line-height: 1.6;
}

/* Services */
.services {
  padding: 5rem 0;
  background: #fff;
}

.services-grid {
  display: grid;
  gap: 2rem;
}

.service-card {
  background: #fff;
  border: 1px solid var(--gray-200);
  border-radius: 0.75rem;
  padding: 2rem;
  transition: box-shadow 0.3s, border-color 0.3s, transform 0.3s;
}
.service-card:hover {
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  border-color: var(--engineering-blue-200);
  transform: translateY(-0.5rem);
}

.service-icon {
  width: 4rem;
  height: 4rem;
  background: var(--engineering-blue-50);
  border-radius: 0.75rem;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
}
.service-icon svg {
  width: 2rem;
  height: 2rem;
  color: var(--engineering-blue-600);
  flex-shrink: 0;
}

.service-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 0 0 1rem;
}
.service-title a {
  color: var(--gray-900);
  text-decoration: none;
}
.service-title a:hover { color: var(--engineering-blue-600); }

.service-desc {
  color: var(--gray-600);
  line-height: 1.6;
  margin: 0 0 1rem;
}

.service-features {
  list-style: none;
  margin: 0;
  padding: 0;
}
.service-features li {
  position: relative;
  padding-left: 1rem;
  font-size: 0.875rem;
  color: var(--gray-600);
  margin-bottom: 0.5rem;
}
.service-features li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.5rem;
  width: 6px;
  height: 6px;
  background: var(--engineering-blue-400);
  border-radius: 50%;
}

.services-cta {
  margin-top: 4rem;
  text-align: center;
  background: var(--engineering-blue-50);
  border-radius: 1rem;
  padding: 2rem;
}
.cta-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 1rem;
}
.cta-text {
  font-size: 1.125rem;
  color: var(--gray-600);
  max-width: 42rem;
  margin: 0 auto 2rem;
  line-height: 1.6;
}

/* About */
.about {
  padding: 5rem 0;
  background: var(--gray-50);
}

.about-grid {
  display: grid;
  gap: 4rem;
  align-items: center;
}

.about-content .section-title { text-align: left; }
.about-content p {
  font-size: 1.125rem;
  color: var(--gray-600);
  line-height: 1.6;
  margin: 0 0 1rem;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  margin-top: 2rem;
}
.about-stat {
  background: #fff;
  padding: 1.5rem;
  border-radius: var(--radius);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}
.about-stat-value {
  display: block;
  font-size: 1.875rem;
  font-weight: 700;
  color: var(--engineering-blue-600);
}
.about-stat-label { color: var(--gray-600); }

.about-media {
  position: relative;
}
.about-media img {
  width: 100%;
  height: 24rem;
  object-fit: cover;
  border-radius: 1rem;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}
.about-badge {
  position: absolute;
  bottom: -1.5rem;
  right: -1.5rem;
  background: var(--engineering-blue-600);
  color: #fff;
  padding: 1.5rem;
  border-radius: 0.75rem;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.2;
}
.about-badge span { font-size: 0.875rem; opacity: 0.9; }

.highlights-title {
  font-size: 1.875rem;
  font-weight: 700;
  text-align: center;
  margin: 5rem 0 3rem;
}

.highlights-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2rem;
}

.highlights-list li {
  text-align: center;
}
.highlight-icon {
  display: inline-block;
  width: 4rem;
  height: 4rem;
  background: var(--engineering-blue-100);
  border-radius: 50%;
  margin-bottom: 1rem;
}
.highlights-list h4 {
  font-size: 1.125rem;
  font-weight: 600;
  margin: 0 0 0.5rem;
}
.highlights-list p {
  font-size: 0.875rem;
  color: var(--gray-600);
  line-height: 1.6;
  margin: 0;
}

/* Contact */
.contact {
  padding: 5rem 0;
  background: #fff;
}

.contact-grid {
  display: grid;
  gap: 4rem;
}

.contact-form-wrap h3,
.contact-info h3 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 1rem;
}
.contact-form-wrap p,
.contact-info > p {
  color: var(--gray-600);
  margin: 0 0 1.5rem;
}

.contact-form .form-row {
  margin-bottom: 1.5rem;
}
.contact-form label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--gray-700);
  margin-bottom: 0.5rem;
}
.contact-form input,
.contact-form select,
.contact-form textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-family: inherit;
  font-size: 1rem;
}
.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--engineering-blue-500);
  box-shadow: 0 0 0 2px rgba(14, 165, 233, 0.3);
}
.contact-form textarea { resize: vertical; min-height: 8rem; }

.contact-form .btn { margin-top: 0.5rem; }

.form-success {
  padding: 1rem;
  background: var(--engineering-blue-50);
  color: var(--engineering-blue-700);
  border-radius: var(--radius);
  font-weight: 500;
}

address.vcard { font-style: normal; }
.contact-block {
  margin: 0 0 1.5rem;
  padding-left: 0;
}
.contact-block strong { display: block; margin-bottom: 0.25rem; }
.contact-block a { color: var(--engineering-blue-600); text-decoration: none; }
.contact-block a:hover { text-decoration: underline; }
.contact-block .hours { font-size: 0.875rem; color: var(--gray-500); }

.contact-cta {
  background: var(--engineering-blue-50);
  padding: 2rem;
  border-radius: 0.75rem;
  margin-top: 2rem;
}
.contact-cta h4 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 0 0 0.75rem;
}
.contact-cta p {
  color: var(--gray-600);
  margin: 0 0 1rem;
}

/* Footer */
.site-footer {
  background: var(--gray-900);
  color: #fff;
  padding: 4rem 0 2rem;
}

.footer-grid {
  display: grid;
  gap: 2rem;
}

.footer-logo {
  height: 2rem;
  width: auto;
  filter: brightness(0) invert(1);
  margin-bottom: 1rem;
}

.footer-brand p {
  color: var(--gray-300);
  line-height: 1.6;
  margin: 0 0 0.5rem;
}
.footer-license {
  font-size: 0.875rem;
  color: var(--gray-400);
}

.footer-col h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin: 0 0 1rem;
}
.footer-col ul {
  list-style: none;
  margin: 0;
  padding: 0;
}
.footer-col li { margin-bottom: 0.75rem; }
.footer-col a {
  color: var(--gray-300);
  text-decoration: none;
}
.footer-col a:hover { color: #fff; }
.footer-col p {
  color: var(--gray-300);
  margin: 0 0 0.5rem;
  font-size: 0.9375rem;
}
.footer-col p a { color: var(--gray-300); }

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  margin-top: 3rem;
  padding-top: 2rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}
.footer-bottom p {
  margin: 0;
  font-size: 0.875rem;
  color: var(--gray-400);
}

/* Desktop */
@media (min-width: 768px) {
  .menu-toggle { display: none; }
  .main-nav {
    display: block;
    position: static;
    background: transparent;
    border: none;
    padding: 0;
  }
  .nav-list {
    display: flex;
    align-items: center;
    gap: 0.5rem;
  }
  .nav-item.has-dropdown .dropdown {
    position: absolute;
    left: 0;
    top: 100%;
    min-width: 20rem;
    padding: 1rem;
    background: #fff;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    border-radius: var(--radius);
    padding-left: 1rem;
  }
  .nav-item.has-dropdown {
    position: relative;
  }
  .nav-item.has-dropdown:hover .dropdown,
  .nav-item.has-dropdown:focus-within .dropdown {
    display: block;
  }
  .nav-item.has-dropdown .dropdown {
    display: none;
  }
}

@media (min-width: 1024px) {
  .hero-grid { grid-template-columns: 1fr 1fr; }
  .hero-title { font-size: 3.75rem; }
  .services-grid { grid-template-columns: repeat(3, 1fr); }
  .about-grid { grid-template-columns: 1fr 1fr; }
  .highlights-list { grid-template-columns: repeat(3, 1fr); }
  .contact-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr repeat(2, 1fr); }
}

@media (min-width: 640px) {
  .hero-actions { flex-direction: row; }
  .services-cta { padding: 3rem; }
  .cta-title { font-size: 1.875rem; }
}

@media (min-width: 768px) {
  .highlights-list { grid-template-columns: repeat(2, 1fr); }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .service-card:hover { transform: none; }
}

/* Technical Library */
.library-intro {
  max-width: 52rem;
  margin: 0 auto 3rem;
  text-align: center;
  color: var(--gray-600);
  line-height: 1.6;
}
.library-category {
  margin-bottom: 4rem;
}
.library-category:last-of-type { margin-bottom: 0; }
.library-category-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 1rem;
  color: var(--engineering-blue-700);
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--engineering-blue-200);
}
.library-table-wrap {
  overflow-x: auto;
  border-radius: var(--radius);
  border: 1px solid var(--gray-200);
  background: #fff;
}
.library-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
}
.library-table th,
.library-table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--gray-200);
}
.library-table th {
  background: var(--engineering-blue-50);
  font-weight: 600;
  color: var(--gray-700);
}
.library-table th:first-child,
.library-table td:first-child { font-weight: 600; color: var(--gray-900); }
.library-table tr:last-child td { border-bottom: none; }
.library-table tbody tr:hover td { background: var(--gray-50); }
.library-life {
  white-space: nowrap;
  font-weight: 600;
  color: var(--engineering-blue-600);
}
@media (max-width: 767px) {
  .library-table th:nth-child(4),
  .library-table td:nth-child(4) { display: none; }
}

/* Leadgen – two-step form */
.leadgen-form {
  max-width: 32rem;
  margin: 0 auto;
}
.leadgen-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 2rem;
  border-bottom: 2px solid var(--gray-200);
}
.leadgen-tab {
  padding: 0.75rem 1.25rem;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--gray-600);
  background: none;
  border: none;
  border-bottom: 3px solid transparent;
  margin-bottom: -2px;
  cursor: pointer;
  font-family: inherit;
  transition: color 0.2s, border-color 0.2s;
}
.leadgen-tab:hover { color: var(--gray-900); }
.leadgen-tab.active {
  color: var(--engineering-blue-600);
  border-bottom-color: var(--engineering-blue-600);
}
.leadgen-panel {
  padding: 0 0 2rem;
}
.leadgen-panel.hidden { display: none !important; }
.leadgen-panel[hidden] { display: none !important; }
.leadgen-panel-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0 0 1.5rem;
  color: var(--gray-900);
}
.leadgen-form .form-row { margin-bottom: 1.5rem; }
.leadgen-form label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--gray-700);
  margin-bottom: 0.5rem;
}
.leadgen-form input,
.leadgen-form select {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-family: inherit;
  font-size: 1rem;
}
.leadgen-form input:focus,
.leadgen-form select:focus {
  outline: none;
  border-color: var(--engineering-blue-500);
  box-shadow: 0 0 0 2px rgba(14, 165, 233, 0.3);
}
.leadgen-form input:invalid:not(:placeholder-shown).touched,
.leadgen-form select:invalid:not([value=""]).touched { border-color: #dc2626; }
.leadgen-actions {
  margin-top: 2rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}
.leadgen-actions-between { justify-content: space-between; }
.leadgen-success {
  max-width: 32rem;
  margin: 0 auto;
  text-align: center;
  padding: 2rem;
}
.leadgen-success .form-success { margin-bottom: 1.5rem; }

/* Learn portal (learn.php) */
.blog-toc {
  background: var(--engineering-blue-50);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  margin-bottom: 2.5rem;
  max-width: 42rem;
}
.blog-toc-title {
  margin: 0 0 0.75rem;
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--gray-900);
}
.blog-toc ul {
  margin: 0;
  padding-left: 1.25rem;
  color: var(--gray-700);
}
.blog-toc li { margin-bottom: 0.35rem; }
.blog-toc a {
  color: var(--engineering-blue-600);
  text-decoration: none;
  font-weight: 500;
}
.blog-toc a:hover { text-decoration: underline; }
.blog-articles {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}
.blog-article .service-title {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
}