/* Reset & Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-stack);
  color: var(--color-text);
  background: var(--color-white);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--color-primary); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--color-primary-dark); }
ul, ol { list-style: none; }

/* Layout */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}
.section {
  padding: var(--space-4xl) 0;
}
.section-alt {
  background: var(--color-bg);
}
.section-dark {
  background: linear-gradient(135deg, var(--color-primary-dark), var(--color-primary));
  color: var(--color-white);
}

/* Typography */
h1, h2, h3, h4, h5, h6 { line-height: 1.3; font-weight: 700; }
h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
p { margin-bottom: var(--space-md); }
.section-title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: var(--space-xl);
  position: relative;
}
.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: var(--color-primary);
  margin: var(--space-md) auto 0;
  border-radius: 2px;
}
.section-subtitle {
  text-align: center;
  color: var(--color-text-muted);
  font-size: 1.125rem;
  max-width: 700px;
  margin: 0 auto var(--space-3xl);
}

/* Header */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-height);
  background: rgba(255,255,255,0.96);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: box-shadow 0.3s;
}
.site-header.scrolled { box-shadow: var(--shadow-sm); }
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}
.logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-text);
}
.logo-img {
  height: 52px;
  width: auto;
}
.logo-text {
  margin: 0;
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-primary-dark);
  line-height: 1;
  letter-spacing: 0.04em;
}
.logo-mark {
  width: 36px; height: 36px;
  background: var(--color-primary);
  border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  color: var(--color-white);
  font-weight: 700; font-size: 1rem;
}
.nav-list {
  display: flex;
  gap: var(--space-xl);
}
.nav-link {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-text);
  padding: var(--space-sm) 0;
  position: relative;
}
.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  width: 0; height: 2px;
  background: var(--color-primary);
  transition: width 0.3s;
}
.nav-link:hover, .nav-link.active {
  color: var(--color-primary);
}
.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}
.mobile-toggle {
  display: none;
  background: none; border: none;
  cursor: pointer;
  padding: var(--space-sm);
}
.mobile-toggle span {
  display: block;
  width: 24px; height: 2px;
  background: var(--color-text);
  margin: 5px 0;
  transition: 0.3s;
}
.mobile-toggle.open span:nth-child(1) { transform: rotate(45deg) translate(5px,5px); }
.mobile-toggle.open span:nth-child(2) { opacity: 0; }
.mobile-toggle.open span:nth-child(3) { transform: rotate(-45deg) translate(5px,-5px); }

/* Footer */
.site-footer {
  background: var(--color-primary-dark);
  color: rgba(255,255,255,0.85);
  padding: var(--space-3xl) 0 var(--space-xl);
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}
.footer-brand .logo {
  color: var(--color-white);
  margin-bottom: var(--space-md);
}
.footer-brand .logo-text {
  font-size: 1.5rem;
  color: var(--color-white);
}
.footer-brand p {
  font-size: 0.875rem;
  line-height: 1.7;
  opacity: 0.8;
}
.footer-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-white);
  margin-bottom: var(--space-lg);
}
.footer-links li { margin-bottom: var(--space-sm); }
.footer-links a {
  color: rgba(255,255,255,0.75);
  font-size: 0.875rem;
}
.footer-links a:hover { color: var(--color-white); }
.footer-contact li {
  font-size: 0.875rem;
  margin-bottom: var(--space-sm);
  display: flex; align-items: flex-start; gap: var(--space-sm);
}
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.15);
  padding-top: var(--space-lg);
  text-align: center;
  font-size: 0.8125rem;
  opacity: 0.7;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 12px 32px;
  font-size: 1rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all 0.3s;
  text-decoration: none;
}
.btn-primary {
  background: var(--color-primary);
  color: var(--color-white);
}
.btn-primary:hover {
  background: var(--color-primary-dark);
  color: var(--color-white);
}
.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}
.btn-outline:hover {
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
}
.btn-white {
  background: var(--color-white);
  color: var(--color-primary);
}
.btn-white:hover {
  background: var(--color-bg);
}

/* Cards */
.card {
  background: var(--color-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  padding: var(--space-2xl);
  transition: transform 0.3s, box-shadow 0.3s;
  border-top: 4px solid var(--color-primary);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.card-icon {
  width: 56px; height: 56px;
  background: var(--color-primary-light);
  border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: var(--space-lg);
  color: var(--color-primary);
}
.card-icon svg {
  width: 28px; height: 28px;
}
.card-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: var(--space-sm);
}
.card-text {
  color: var(--color-text-muted);
  font-size: 0.9375rem;
  line-height: 1.7;
}

/* Grid utilities */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-xl); }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-xl); }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-xl); }

/* Hero */
.hero {
  position: relative;
  min-height: 600px;
  display: flex; align-items: center;
  padding-top: var(--header-height);
  overflow: hidden;
}
.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: rgba(13,71,161,0.75);
  z-index: 1;
}
.hero-content {
  position: relative; z-index: 2;
  max-width: 800px;
  color: var(--color-white);
}
.hero-title {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: var(--space-lg);
  line-height: 1.2;
}
.hero-desc {
  font-size: 1.25rem;
  opacity: 0.9;
  margin-bottom: var(--space-xl);
  line-height: 1.7;
}
.hero-actions { display: flex; gap: var(--space-md); }

/* Scroll reveal */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Back to top */
.back-to-top {
  position: fixed;
  bottom: 32px; right: 32px;
  width: 48px; height: 48px;
  border-radius: 50%;
  background: var(--color-primary);
  color: var(--color-white);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  border: none;
  box-shadow: var(--shadow-md);
  opacity: 0; visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s, background 0.3s;
  z-index: 999;
}
.back-to-top.show { opacity: 1; visibility: visible; }
.back-to-top:hover { background: var(--color-primary-dark); }

/* Responsive */
@media (max-width: 1023px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-title { font-size: 2.25rem; }
}

@media (max-width: 767px) {
  .nav-list {
    position: fixed;
    top: var(--header-height); left: 0; right: 0;
    background: rgba(255,255,255,0.98);
    flex-direction: column;
    padding: var(--space-lg);
    gap: 0;
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.3s, opacity 0.3s, visibility 0.3s;
  }
  .nav-list.open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  .nav-link { padding: var(--space-md) 0; border-bottom: 1px solid var(--color-border); }
  .nav-link::after { display: none; }
  .mobile-toggle { display: block; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: var(--space-xl); }
  .section { padding: var(--space-2xl) 0; }
  .hero { min-height: 480px; }
  .hero-title { font-size: 1.875rem; }
  .hero-desc { font-size: 1rem; }
  .hero-actions { flex-direction: column; }
  h2 { font-size: 1.625rem; }
  h3 { font-size: 1.25rem; }
}