:root {
  /* -- Variant B Design System -- */
  /* Colors */
  --bg-main: #f5f6f8;
  --bg-section: #ffffff;
  --text-main: #111827;
  /* near-black / antracite */
  --text-muted: #6b7280;
  /* cool gray */
  --text-inverse: #ffffff;

  --primary: #111827;
  /* antracite - confident, serious */
  --accent: #6366f1;
  /* indigo - modern, expressive */
  --accent-hover: #4f46e5;
  --border: #e5e7eb;

  /* Typography */
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
  --line-height-base: 1.6;
  --line-height-heading: 1.2;

  /* Scale */
  --h1-size: clamp(2.5rem, 5vw, 3.75rem);
  --h2-size: clamp(2rem, 4vw, 2.75rem);
  --h3-size: 1.35rem;
  --text-base: 1rem;
  --text-sm: 0.9rem;

  /* Spacing & Layout */
  --container-width: 1100px;
  --header-height: 72px;
  --spacing-section: 6rem;
  --spacing-block: 2.5rem;
  --radius: 12px;
  --shadow: 0 12px 35px rgba(0, 0, 0, 0.08);
  --shadow-hover: 0 20px 40px rgba(0, 0, 0, 0.12);
  --shadow-card: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--line-height-base);
  color: var(--text-main);
  background-color: var(--bg-main);
  -webkit-font-smoothing: antialiased;
}

/* Typography */
h1,
h2,
h3,
h4 {
  font-weight: 800;
  /* Bolder than A */
  color: var(--primary);
  line-height: var(--line-height-heading);
  margin-bottom: 1rem;
}

h1 {
  font-size: var(--h1-size);
  letter-spacing: -0.025em;
}

h2 {
  font-size: var(--h2-size);
  letter-spacing: -0.02em;
  margin-bottom: 3rem;
  text-align: center;
}

h3 {
  font-size: var(--h3-size);
  color: var(--primary);
  font-weight: 700;
}

p {
  max-width: 68ch;
  margin-bottom: 1.5rem;
  color: var(--text-muted);
}

a {
  text-decoration: none;
  color: inherit;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

ul {
  list-style: none;
}

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

/* Layout Utilities */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

section {
  padding: var(--spacing-section) 0;
  position: relative;
}

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

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

.mx-auto {
  margin-left: auto;
  margin-right: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.98);
  height: var(--header-height);
  z-index: 100;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
  /* Modern flat shadow */
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: 800;
  font-size: 1.4rem;
  color: var(--primary);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  letter-spacing: -0.02em;
}

.logo svg {
  color: var(--accent);
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 2.5rem;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-muted);
}

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

.btn-header {
  padding: 0.6rem 1.4rem !important;
  font-size: 0.9rem !important;
  border-radius: 999px !important;
  /* Pill shape for modernize */
}

/* Mobile Toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.bar {
  display: block;
  width: 24px;
  height: 2.5px;
  background: var(--primary);
  margin: 5px 0;
  transition: 0.3s;
  border-radius: 2px;
}

/* Hero Section */
.hero {
  position: relative;
  min-height: 85vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  background-color: var(--primary);
  /* Fallback */
  background-image: url('assets/hero-work.jpg');
  background-size: cover;
  background-position: center;
  color: var(--text-inverse);
  padding: 5rem 1.5rem;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(17, 24, 39, 0.75), rgba(17, 24, 39, 0.6));
  /* Lighter overlay than A */
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
}

.hero h1 {
  color: var(--text-inverse);
  margin-bottom: 1.5rem;
  text-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

.hero p {
  color: rgba(255, 255, 255, 0.95);
  font-size: 1.25rem;
  font-weight: 500;
  margin-bottom: 3rem;
  margin-left: auto;
  margin-right: auto;
  max-width: 65ch;
}

.hero-actions {
  display: flex;
  gap: 1.25rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.9rem 2.25rem;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: 1rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-primary {
  background-color: var(--accent);
  color: white;
  box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.39);
}

.btn-primary:hover {
  background-color: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.23);
}

.btn-secondary {
  background-color: rgba(255, 255, 255, 0.1);
  color: white;
  border: 1px solid rgba(255, 255, 255, 0.4);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover {
  background-color: rgba(255, 255, 255, 0.2);
  border-color: rgba(255, 255, 255, 0.8);
}

/* Cards & Grid */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2.5rem;
}

.card {
  background: white;
  padding: 3rem 2.5rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  transition: transform 0.3s, box-shadow 0.3s;
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow);
  border-color: #d1d5db;
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--accent);
  opacity: 0;
  transition: opacity 0.3s;
}

.card:hover::before {
  opacity: 1;
}

.icon-box {
  width: 56px;
  height: 56px;
  background: #eff0ff;
  /* Light indigo tint */
  color: var(--accent);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 2rem;
}

.icon-box svg {
  width: 28px;
  height: 28px;
}

/* Checklist Styling */
.checklist-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
  gap: 2rem;
}

.check-item {
  background: white;
  padding: 2rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  border: 1px solid var(--border);
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
  transition: 0.2s;
}

.check-item:hover {
  border-color: var(--accent);
}

.check-icon {
  color: var(--accent);
  flex-shrink: 0;
  width: 24px;
  margin-top: 3px;
  background: #eff0ff;
  border-radius: 50%;
  padding: 3px;
}

/* Common Findings (Mini Section) */
.features-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2.5rem;
  margin-top: 5rem;
  text-align: center;
  padding-top: 5rem;
  border-top: 1px solid var(--border);
}

.feature-item h3 {
  color: var(--accent);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 1rem;
  font-weight: 800;
}

.feature-item p {
  font-weight: 600;
  color: var(--primary);
  font-size: 1.1rem;
}

/* Comparison Example */
.comparison-card {
  background: white;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  border: 1px solid var(--border);
}

.comparison-header {
  background: #fafafa;
  padding: 1.5rem;
  text-align: center;
  font-weight: 700;
  border-bottom: 1px solid var(--border);
  color: var(--primary);
}

.compare-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.compare-col {
  padding: 3rem;
  border-right: 1px solid var(--border);
}

.compare-col:last-child {
  border-right: none;
}

.bad-ex {
  background: #fffafa;
}

.bad-ex strong {
  color: #dc2626;
  display: block;
  margin-bottom: 1rem;
}

.good-ex {
  background: #fdfcff;
}

.good-ex strong {
  color: var(--accent);
  display: block;
  margin-bottom: 1rem;
}

/* Contact Form */
.contact-card {
  background: white;
  padding: 3.5rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  max-width: 650px;
  margin: 0 auto;
  border: 1px solid var(--border);
  position: relative;
}

.form-group {
  margin-bottom: 1.75rem;
}

.label {
  display: block;
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--primary);
}

.input,
.textarea {
  width: 100%;
  padding: 1rem 1.25rem;
  font-size: 1rem;
  border: 2px solid var(--border);
  /* Slightly thicker border */
  border-radius: var(--radius);
  background: #f9fafb;
  font-family: inherit;
  transition: 0.2s;
  color: var(--primary);
}

.input:focus,
.textarea:focus {
  background: white;
  border-color: var(--accent);
  outline: none;
  box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
}

.helper-text {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
}

/* Footer */
.footer {
  background: white;
  border-top: 1px solid var(--border);
  padding: 5rem 0;
  font-size: 0.95rem;
  color: var(--text-muted);
}

.footer strong {
  color: var(--primary);
  font-size: 1.1rem;
}

/* Responsive */
@media (max-width: 768px) {
  :root {
    --header-height: 64px;
    --h1-size: 2.75rem;
    --spacing-section: 4rem;
  }

  .hero {
    min-height: auto;
    padding-top: 7rem;
    padding-bottom: 5rem;
  }

  .nav-desktop {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background: white;
    flex-direction: column;
    padding: 2.5rem;
    align-items: center;
    /* Center align for modern mobile feel */
    border-bottom: 1px solid var(--border);
    transform: translateY(-150%);
    transition: transform 0.3s ease;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  }

  .nav-desktop.open {
    transform: translateY(0);
  }

  .nav-link {
    font-size: 1.1rem;
  }

  .mobile-toggle {
    display: block;
  }

  .compare-row {
    grid-template-columns: 1fr;
  }

  .compare-col {
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding: 2rem;
  }

  .features-list {
    grid-template-columns: 1fr;
    text-align: left;
    padding-top: 3rem;
  }

  .contact-card {
    padding: 2rem;
  }
}