/* ============================================
   AB Labs - Professional Intelligence Consulting
   Clean, minimal, confident design
   ============================================ */

/* === CSS Custom Properties === */
:root {
  /* Colors - restrained palette */
  --bg-primary: #1a1d23;
  --bg-secondary: #252932;
  --text-primary: #e4e6eb;
  --text-secondary: #9199a1;
  --accent: #4a9eff;
  --border: #2d3139;

  /* Typography */
  --font-main: 'IBM Plex Mono', 'Consolas', 'Monaco', 'Courier New', monospace;
  --font-size-base: 18px;
  --line-height-base: 1.7;

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;

  /* Layout */
  --max-content-width: 900px;
  --border-radius: 4px;

  /* Transitions */
  --transition-speed: 0.2s;
}

/* === Reset & Base === */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: var(--font-size-base);
}

body {
  font-family: var(--font-main);
  line-height: var(--line-height-base);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* === Typography === */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.3;
  margin-bottom: var(--spacing-md);
  font-weight: 500;
}

h1 {
  font-size: 2.5rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 1.75rem;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.25rem;
}

p {
  margin-bottom: var(--spacing-md);
}

p:last-child {
  margin-bottom: 0;
}

a {
  color: var(--text-primary);
  text-decoration: underline;
  text-decoration-color: var(--border);
  text-underline-offset: 3px;
  transition: all var(--transition-speed) ease;
}

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

/* === Navigation === */
.nav {
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: background-color var(--transition-speed) ease;
}

.nav.scrolled {
  background-color: rgba(26, 29, 35, 0.95);
  backdrop-filter: blur(10px);
}

.nav-container {
  max-width: var(--max-content-width);
  margin: 0 auto;
  padding: var(--spacing-md) var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.25rem;
  font-weight: 500;
  text-decoration: none;
  letter-spacing: 0.05em;
}

.logo:hover {
  color: var(--text-primary);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: var(--spacing-md);
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  text-transform: uppercase;
  font-size: 0.85rem;
  letter-spacing: 0.1em;
  font-weight: 400;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: var(--spacing-xs);
}

/* === Layout Containers === */
.container {
  max-width: var(--max-content-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.section {
  padding: var(--spacing-xl) 0;
}

.section-tight {
  padding: var(--spacing-lg) 0;
}

/* === Hero Section === */
.hero {
  text-align: center;
  padding: var(--spacing-xl) 0;
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  position: relative;
  overflow: hidden;
}

#particle-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none; /* Allow clicks to pass through to content */
}

.hero .container {
  position: relative;
  z-index: 10;
  width: 100%;
}

/* Hero Content Wrapper - Two Column Layout */
.hero-content-wrapper {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-lg);
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
}

.hero-left {
  flex: 0 0 50%;
  text-align: left;
  z-index: 10;
}

.hero-right {
  flex: 0 0 45%;
  min-height: 500px;
  position: relative;
  z-index: 5;
}

.hero-logo {
  font-size: 3rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  margin-bottom: var(--spacing-md);
  text-align: left;
}

.hero-tagline {
  font-size: 2rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
  text-align: left;
}

.hero-description {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 100%;
  margin: 0 0 var(--spacing-lg) 0;
  line-height: 1.8;
  text-align: left;
}

.hero-left .btn {
  margin-top: var(--spacing-sm);
}

/* === Buttons === */
.btn {
  display: inline-block;
  padding: 0.875rem 2rem;
  background-color: var(--accent);
  color: var(--bg-primary);
  text-decoration: none;
  border-radius: var(--border-radius);
  font-weight: 500;
  font-size: 0.95rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  transition: all var(--transition-speed) ease;
  border: none;
  cursor: pointer;
  font-family: var(--font-main);
}

.btn:hover {
  background-color: #6bb0ff;
  color: var(--bg-primary);
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

/* === Grid Layouts === */
.grid {
  display: grid;
  gap: var(--spacing-md);
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

/* === Cards === */
.card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--border-radius);
  padding: var(--spacing-md);
  transition: border-color var(--transition-speed) ease;
}

.card:hover {
  border-color: rgba(74, 158, 255, 0.3);
}

.card h3 {
  margin-bottom: var(--spacing-sm);
  font-size: 1.15rem;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* === Service Cards === */
.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

/* === Approach Grid === */
.approach-grid {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
}

.approach-item {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: var(--spacing-md);
  align-items: start;
}

.approach-item h4 {
  margin-bottom: 0;
  font-size: 1rem;
  color: var(--accent);
  text-align: right;
  padding-right: var(--spacing-sm);
}

.approach-item p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 0;
}

/* === Testimonials === */
.testimonial-grid {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.testimonial {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--border-radius);
  padding: var(--spacing-md);
  transition: border-color var(--transition-speed) ease;
}

.testimonial:hover {
  border-color: rgba(74, 158, 255, 0.3);
}

.testimonial-quote {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text-secondary);
  font-style: italic;
  margin-bottom: var(--spacing-md);
  position: relative;
}

.testimonial-quote::before {
  content: '"';
  font-size: 2rem;
  color: var(--accent);
  position: absolute;
  left: -10px;
  top: -5px;
  opacity: 0.3;
}

.testimonial-attribution {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
  margin-bottom: 0;
}

/* === Content Sections === */
.content-section {
  margin-bottom: var(--spacing-xl);
}

.content-section:last-child {
  margin-bottom: 0;
}

.content-section h2 {
  border-bottom: 1px solid var(--border);
  padding-bottom: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.content-section p {
  color: var(--text-secondary);
}

.content-section ul {
  list-style: none;
  margin: var(--spacing-md) 0;
}

.content-section li {
  padding-left: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
  position: relative;
  color: var(--text-secondary);
}

.content-section li::before {
  content: "//";
  position: absolute;
  left: 0;
  color: var(--accent);
}

/* Lead sentences for long-form content */
.lead-sentence {
  font-size: 1.15em;
  font-weight: 500;
  color: var(--text-primary);
}

.content-section p strong {
  color: var(--text-primary);
  font-weight: 500;
}

/* === Forms === */
.form-group {
  margin-bottom: var(--spacing-md);
}

label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-size: 0.9rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

input[type="text"],
input[type="email"],
textarea {
  width: 100%;
  padding: 0.875rem;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--border-radius);
  color: var(--text-primary);
  font-family: var(--font-main);
  font-size: 0.95rem;
  transition: border-color var(--transition-speed) ease;
}

input[type="text"]:focus,
input[type="email"]:focus,
textarea:focus {
  outline: none;
  border-color: var(--accent);
}

textarea {
  min-height: 180px;
  resize: vertical;
}

.form-note {
  margin-top: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: var(--bg-secondary);
  border-left: 2px solid var(--accent);
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* === Page Headers === */
.page-header {
  padding: var(--spacing-lg) 0 var(--spacing-md) 0;
  text-align: center;
  border-bottom: 1px solid var(--border);
  margin-bottom: var(--spacing-lg);
}

.page-header h1 {
  margin-bottom: var(--spacing-sm);
}

.page-header p {
  color: var(--text-secondary);
  font-size: 1.05rem;
}

/* === Footer === */
.footer {
  border-top: 1px solid var(--border);
  padding: var(--spacing-lg) 0;
  margin-top: var(--spacing-xl);
  text-align: center;
}

.footer-divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: var(--spacing-md) 0;
}

.footer-contact {
  font-size: 1.1rem;
  margin-bottom: var(--spacing-sm);
}

.footer-contact a {
  text-decoration: none;
}

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

.footer-links {
  display: flex;
  justify-content: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
  font-size: 0.9rem;
}

.footer-company,
.footer-copyright {
  color: var(--text-secondary);
  font-size: 0.85rem;
  margin-bottom: var(--spacing-xs);
}

/* === Coordinate Divider === */
.coord-divider {
  position: relative;
  text-align: center;
  margin: var(--spacing-lg) 0;
  height: 1px;
  background: linear-gradient(to right, transparent, var(--border) 20%, var(--border) 80%, transparent);
}

.coord-divider span {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background-color: var(--bg-primary);
  padding: 0 var(--spacing-md);
  font-size: 0.75rem;
  color: var(--text-secondary);
  letter-spacing: 0.15em;
  white-space: nowrap;
}

/* === Utility Classes === */
.text-center {
  text-align: center;
}

.text-secondary {
  color: var(--text-secondary);
}

.mb-lg {
  margin-bottom: var(--spacing-lg);
}

.mt-lg {
  margin-top: var(--spacing-lg);
}

/* === Responsive Design === */

/* Hide canvas on tablets and mobile */
@media (max-width: 1024px) {
  #particle-canvas {
    display: none !important;
  }
}

/* Tablet */
@media (max-width: 1024px) {
  :root {
    --font-size-base: 17px;
    --spacing-xl: 4rem;
  }

  /* Stack hero vertically on tablet */
  .hero-content-wrapper {
    flex-direction: column;
    text-align: center;
  }

  .hero-left {
    flex: 1;
    text-align: center;
  }

  .hero-right {
    display: none;
  }

  .hero-logo,
  .hero-tagline,
  .hero-description {
    text-align: center;
  }

  .hero-description {
    margin: 0 auto var(--spacing-lg) auto;
    max-width: 700px;
  }

  .hero-logo {
    font-size: 2.5rem;
  }

  .hero-tagline {
    font-size: 1.65rem;
  }

  h1 {
    font-size: 2.25rem;
  }

  h2 {
    font-size: 1.6rem;
  }

  /* Approach items stack on tablet */
  .approach-item {
    grid-template-columns: 140px 1fr;
  }

  .approach-item h4 {
    font-size: 0.95rem;
  }
}

/* Mobile */
@media (max-width: 640px) {
  :root {
    --font-size-base: 16px;
    --spacing-md: 1.5rem;
    --spacing-lg: 3rem;
    --spacing-xl: 3rem;
  }

  .nav-container {
    padding: var(--spacing-sm) var(--spacing-md);
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: var(--spacing-md);
    gap: var(--spacing-sm);
  }

  .nav-links.active {
    display: flex;
  }

  .mobile-menu-toggle {
    display: block;
  }

  .hero {
    min-height: 60vh;
    padding: var(--spacing-lg) 0;
  }

  /* Hide canvas visualization on mobile */
  #particle-canvas {
    display: none;
  }

  /* Stack hero vertically and center on mobile */
  .hero-content-wrapper {
    flex-direction: column;
    text-align: center;
  }

  .hero-left {
    flex: 1;
    text-align: center;
  }

  .hero-right {
    display: none;
  }

  .hero-logo,
  .hero-tagline,
  .hero-description {
    text-align: center;
  }

  .hero-description {
    margin: 0 auto var(--spacing-lg) auto;
    max-width: 700px;
  }

  .hero-logo {
    font-size: 2rem;
  }

  .hero-tagline {
    font-size: 1.35rem;
  }

  .hero-description {
    font-size: 1rem;
  }

  h1 {
    font-size: 1.85rem;
  }

  h2 {
    font-size: 1.4rem;
  }

  /* Approach items fully stack on mobile */
  .approach-item {
    grid-template-columns: 1fr;
    gap: var(--spacing-xs);
  }

  .approach-item h4 {
    text-align: left;
    padding-right: 0;
    margin-bottom: var(--spacing-xs);
  }

  .services-grid,
  .grid-2,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .section {
    padding: var(--spacing-lg) 0;
  }

  .coord-divider span {
    font-size: 0.65rem;
    padding: 0 var(--spacing-sm);
  }
}