:root {
  --color-bg: #ffffff;
  --color-surface: #f5f7fa;
  --color-border: #e2e8f0;
  --color-text: #1a2333;
  --color-text-secondary: #4b5768;
  --color-primary: #1d4ed8;
  --color-primary-dark: #1e3a8a;
  --color-primary-contrast: #ffffff;
  --max-width: 1080px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
}

h1, h2, h3 {
  line-height: 1.25;
  font-weight: 700;
}

h1 { font-size: 2.25rem; }
h2 { font-size: 1.75rem; margin-bottom: 1.5rem; }
h3 { font-size: 1.15rem; margin: 0 0 0.5rem; }

p { margin: 0 0 1rem; color: var(--color-text-secondary); }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

a {
  color: var(--color-primary);
  text-decoration: none;
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-weight: 600;
  text-decoration: none;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-primary-contrast);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  z-index: 100;
}

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

.logo {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-text);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.site-nav a {
  color: var(--color-text-secondary);
  font-weight: 500;
}

.site-nav a:hover {
  color: var(--color-primary);
}

.nav-cta {
  color: var(--color-primary) !important;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
}

/* Hero */
.hero {
  padding: 5rem 0 4rem;
  text-align: center;
  background: linear-gradient(180deg, var(--color-surface), var(--color-bg));
}

.hero h1 {
  max-width: 720px;
  margin: 0 auto 1.25rem;
}

.hero-sub {
  max-width: 600px;
  margin: 0 auto 2rem;
  font-size: 1.1rem;
}

/* Sections */
.section {
  padding: 4rem 0;
}

.section-alt {
  background: var(--color-surface);
}

.section-intro {
  max-width: 700px;
}

.contact-section {
  text-align: center;
}

/* Cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.card-grid.three-up {
  grid-template-columns: repeat(3, 1fr);
}

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 1.5rem;
}

.section-alt .card {
  background: var(--color-bg);
}

.card-plain {
  background: transparent;
}

.card-wide {
  grid-column: 1 / -1;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 1.5rem 0;
  text-align: center;
}

.site-footer p {
  margin: 0;
  font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 720px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    align-items: flex-start;
    padding: 1rem 1.5rem;
    gap: 1rem;
    display: none;
  }

  .site-nav.open {
    display: flex;
  }

  .card-grid,
  .card-grid.three-up {
    grid-template-columns: 1fr;
  }

  h1 {
    font-size: 1.75rem;
  }
}