/* css/main.css */
:root {
  /* Sleek Monochrome Light Theme Colors */
  --accent: #000000;
  --accent-dark: #1A1A1A;
  --accent-light: #9CA3AF;
  --accent-soft: #F4F4F5;
  
  /* Semantic Status Colors (Preserved for UX) */
  --safe: #157F5A;
  --safe-soft: #EAF6F1;
  --caution: #B4740E;
  --caution-soft: #FBF3E7;
  --danger: #C4321F;
  --danger-soft: #FCEEEC;

  /* Greyscale Neutrals */
  --gray-50: #FAFAFA;
  --gray-100: #F4F4F5;
  --gray-200: #E4E4E7;
  --gray-400: #A1A1AA;
  --gray-500: #71717A;
  --gray-800: #27272A;
  --gray-900: #18181B;

  /* Light Backgrounds */
  --bg-base: #FFFFFF;
  --bg-surface: #FFFFFF;
  --bg-surface-border: #E5E7EB;

  /* Terminal / Secondary Sections */
  --ink-950: #FAFAFA;
  --ink-900: #FFFFFF;
  --ink-line: rgba(0, 0, 0, 0.06);
  --ink-text: #71717A;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-display: 'Space Grotesk', var(--font-sans);
  --font-mono: 'IBM Plex Mono', 'SFMono-Regular', Consolas, monospace;
  --max-width: 1100px;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 8px 24px -8px rgba(0, 0, 0, 0.12);
  --shadow-lg: 0 24px 48px -14px rgba(0, 0, 0, 0.18);
  --shadow-accent: 0 10px 24px -6px rgba(0, 0, 0, 0.35);
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  color: var(--gray-800);
  line-height: 1.6;
  background-color: var(--bg-base);
  background-image:
    linear-gradient(rgba(0, 0, 0, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 0, 0, 0.02) 1px, transparent 1px);
  background-size: 42px 42px;
  -webkit-font-smoothing: antialiased;
}

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* Typography */
h1, h2, h3 { color: var(--gray-900); line-height: 1.15; font-family: var(--font-display); }
h1 { font-size: clamp(2.25rem, 1.5rem + 3vw, 3.75rem); font-weight: 700; letter-spacing: -0.03em; }
h2 { font-size: 1.9rem; font-weight: 600; margin-bottom: 1rem; letter-spacing: -0.01em; }
h3 { font-size: 1.2rem; font-weight: 600; margin-bottom: 0.5rem; }
p { color: var(--gray-500); margin-bottom: 1rem; }
a { color: var(--accent); text-decoration: none; transition: opacity 0.2s var(--ease); }
a:hover { opacity: 0.8; }

.text-center { text-align: center; }
.section-intro { max-width: 600px; margin: 0 auto 40px; text-align: center; }
.section-intro p { margin-bottom: 0; }

/* Header / Navigation */
.site-header {
  border-bottom: 1px solid var(--bg-surface-border);
  padding: 16px 0;
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  z-index: 100;
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0);
  transition: box-shadow 0.3s var(--ease);
}
.site-header.scrolled { box-shadow: var(--shadow-md); }

.nav-container { display: flex; justify-content: space-between; align-items: center; position: relative; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 1.2rem; font-family: var(--font-display); color: var(--gray-900); }
.logo-img {
  width: 32px;
  height: 32px;
  object-fit: contain;
  display: block;
}
.nav-links { display: flex; gap: 28px; align-items: center; }
.nav-links a:not(.btn) { color: var(--gray-500); font-weight: 500; font-size: 0.95rem; position: relative; padding-bottom: 2px; }
.nav-links a:not(.btn)::after {
  content: ''; position: absolute; left: 0; bottom: -4px; width: 0%; height: 1.5px;
  background: var(--accent); transition: width 0.25s var(--ease);
}
.nav-links a:not(.btn):hover { color: var(--gray-900); opacity: 1; }
.nav-links a:not(.btn):hover::after { width: 100%; }
.nav-cta { padding: 9px 18px; font-size: 0.9rem; }

.menu-toggle { display: none; flex-direction: column; justify-content: center; gap: 5px; width: 32px; height: 32px; background: none; border: none; cursor: pointer; padding: 0; z-index: 101; }
.menu-toggle span { display: block; width: 100%; height: 2px; background: var(--gray-800); border-radius: 2px; transition: transform 0.25s var(--ease), opacity 0.2s var(--ease); }
.menu-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle.open span:nth-child(2) { opacity: 0; }
.menu-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Footer */
.site-footer { border-top: 1px solid var(--bg-surface-border); padding: 40px 0; text-align: center; font-size: 0.9rem; color: var(--gray-400); }
.footer-links { margin-bottom: 16px; display: flex; justify-content: center; gap: 24px; }
.footer-links a { color: var(--gray-500); }
.footer-links a:hover { color: var(--gray-900); }
.site-footer p { font-family: var(--font-mono); font-size: 0.78rem; margin-bottom: 0; }

@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; } }