/* ============================================================================
   CompanyGrowthSignal.com - Main CSS
   Dark SaaS Theme with all design system tokens
   ============================================================================ */

:root {
  /* Backgrounds */
  --bg-primary:    #0a0b0d;
  --bg-secondary:  #111318;
  --bg-tertiary:   #1a1d26;
  --border:        #1e2130;
  --border-active: #2e3347;

  /* Text */
  --text-primary:  #f0f2f7;
  --text-secondary: #9ba3b8;
  --text-muted:    #5e6678;

  /* Signal Colors */
  --signal-green:  #22c55e;
  --signal-red:    #ef4444;
  --signal-amber:  #f59e0b;
  --signal-blue:   #3b82f6;
  --signal-purple: #8b5cf6;

  /* Accent (Indigo) */
  --accent:        #6366f1;
  --accent-hover:  #4f46e5;
  --accent-glow:   rgba(99, 102, 241, 0.15);

  /* CTA Green */
  --cta-green:     #10b981;
  --cta-green-hover: #059669;

  /* Typography */
  --font-heading: 'Inter', system-ui, -apple-system, sans-serif;
  --font-body:    'Inter', system-ui, -apple-system, sans-serif;
  --font-mono:    'JetBrains Mono', 'Fira Code', ui-monospace, monospace;

  /* Font Sizes */
  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  1.875rem;
  --text-4xl:  2.25rem;
  --text-5xl:  3rem;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-24: 6rem;

  /* Borders */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.5);
  --shadow-glow: 0 0 20px var(--accent-glow);

  /* Layout */
  --max-width: 1200px;
  --nav-height: 64px;
}

/* ============================================================================
   Reset & Base Styles
   ============================================================================ */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--text-secondary);
  background: var(--bg-primary);
  line-height: 1.6;
  min-height: 100vh;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--accent-hover);
}

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

/* ============================================================================
   Layout
   ============================================================================ */

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.section {
  padding: var(--space-24) 0;
}

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

/* ============================================================================
   Grid System
   ============================================================================ */

.grid {
  display: grid;
  gap: var(--space-6);
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

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

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 1024px) {
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
  .container {
    padding: 0 var(--space-4);
  }
}

/* ============================================================================
   Typography
   ============================================================================ */

h1, h2, h3, h4 {
  color: var(--text-primary);
  font-family: var(--font-heading);
}

h1 {
  font-size: var(--text-5xl);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: var(--space-6);
}

h2 {
  font-size: var(--text-4xl);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-bottom: var(--space-4);
}

h3 {
  font-size: var(--text-2xl);
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-3);
}

h4 {
  font-size: var(--text-xl);
  font-weight: 600;
  margin-bottom: var(--space-2);
}

p {
  margin-bottom: var(--space-4);
}

/* ============================================================================
   Navigation
   ============================================================================ */

.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 11, 13, 0.8);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  height: var(--nav-height);
  display: flex;
  align-items: center;
}

.nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.nav-logo {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-logo .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--signal-green);
  display: inline-block;
}

.nav-links {
  display: flex;
  gap: var(--space-6);
  align-items: center;
}

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

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

.nav-cta {
  background: var(--accent);
  color: white;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: background 0.2s;
}

.nav-cta:hover {
  background: var(--accent-hover);
  color: white;
}

.nav-mobile-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  font-size: var(--text-xl);
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    padding: var(--space-4);
    border-bottom: 1px solid var(--border);
  }
  .nav-mobile-toggle {
    display: block;
  }
}

/* ============================================================================
   Footer
   ============================================================================ */

.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: var(--space-16) 0 var(--space-8);
  margin-top: var(--space-24);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-8);
}

.footer-brand {
  max-width: 300px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: var(--text-sm);
  margin-top: var(--space-2);
}

.footer-col h4 {
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: var(--space-4);
}

.footer-col a {
  display: block;
  color: var(--text-secondary);
  font-size: var(--text-sm);
  padding: var(--space-1) 0;
}

.footer-col a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  margin-top: var(--space-8);
  padding-top: var(--space-6);
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  font-size: var(--text-xs);
  flex-wrap: wrap;
  gap: var(--space-4);
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

/* ============================================================================
   Scrollbars
   ============================================================================ */

::-webkit-scrollbar {
  width: 16px;
}

::-webkit-scrollbar-track {
  background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-active);
  border: 4px solid transparent;
  background-clip: padding-box;
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
  background-clip: padding-box;
  border: 4px solid transparent;
}