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

:root {
  --color-bg: #ffffff;
  --color-fg: #1a1a1a;
  --color-text-secondary: #666666;
  --color-border: #e8e8e8;
  --color-accent: #0066cc;
  --color-accent-light: #f0f4ff;

  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-size-base: 16px;
  --line-height-relaxed: 1.8;
  --letter-spacing-tight: -0.01em;

  --spacing-xs: 8px;
  --spacing-sm: 12px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-2xl: 48px;
  --spacing-3xl: 64px;
  --spacing-4xl: 96px;

  --border-radius: 8px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);

  --transition-fast: 150ms ease-out;
  --transition-normal: 250ms ease-out;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: var(--line-height-relaxed);
  color: var(--color-fg);
  background-color: var(--color-bg);
  letter-spacing: var(--letter-spacing-tight);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  letter-spacing: var(--letter-spacing-tight);
  line-height: 1.3;
  margin-bottom: var(--spacing-lg);
}

h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
}

h2 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 600;
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
}

h4 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: var(--spacing-md);
}

p {
  margin-bottom: var(--spacing-lg);
  color: var(--color-text-secondary);
}

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

a:hover {
  color: #0052a3;
}

/* Containers */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

/* Header / Navigation */
.header {
  position: sticky;
  top: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: all var(--transition-normal);
}

.header.scrolled {
  box-shadow: var(--shadow-md);
}

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

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--color-fg);
  transition: opacity var(--transition-fast);
}

.nav-logo:hover {
  opacity: 0.7;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-2xl);
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  position: relative;
  transition: color var(--transition-fast);
}

.nav-link:hover {
  color: var(--color-fg);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--transition-fast);
}

.nav-link:hover::after {
  width: 100%;
}

@media (max-width: 768px) {
  .nav-menu {
    gap: var(--spacing-lg);
    font-size: 0.9rem;
  }
}

/* Hero Section */
.hero {
  padding: var(--spacing-3xl) 0 var(--spacing-2xl) 0;
  background: var(--color-bg);
}

.hero-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-3xl);
  align-items: center;
}

.hero-content {
  animation: fadeInUp 0.8s ease-out;
}

.hero-title {
  margin-bottom: var(--spacing-lg);
  line-height: 1.2;
}

.hero-subtitle {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-2xl);
  max-width: 500px;
  line-height: 1.7;
}

.hero-image {
  animation: fadeInUp 0.8s ease-out 0.1s both;
}

.hero-image img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
}

@media (max-width: 1024px) {
  .hero-container {
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
  }

  .hero {
    padding: var(--spacing-2xl) 0;
  }
}

/* CTA Button */
.cta-button {
  display: inline-block;
  padding: var(--spacing-md) var(--spacing-xl);
  background: var(--color-accent);
  color: white;
  border-radius: var(--border-radius);
  font-weight: 500;
  font-size: 0.95rem;
  border: 2px solid var(--color-accent);
  transition: all var(--transition-fast);
  cursor: pointer;
  text-decoration: none;
}

.cta-button:hover {
  background: #0052a3;
  border-color: #0052a3;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: white;
}

.cta-button:active {
  transform: translateY(0);
}

.cta-primary {
  background: var(--color-accent);
  border: 2px solid var(--color-accent);
  color: white;
}

/* Work / Case Studies Section */
.work {
  padding: var(--spacing-4xl) 0;
  background: var(--color-bg);
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
  opacity: 0;
  animation: fadeInUp 0.8s ease-out 0.2s forwards;
}

.case-study {
  margin-bottom: var(--spacing-4xl);
  opacity: 0;
  animation: fadeInUp 0.8s ease-out forwards;
}

.case-study:nth-child(2) {
  animation-delay: 0.3s;
}

.case-study:nth-child(3) {
  animation-delay: 0.4s;
}

.case-study:nth-child(4) {
  animation-delay: 0.5s;
}

.case-study-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-3xl);
  align-items: center;
}

.case-study-content.reverse {
  grid-template-columns: 1fr 1fr;
}

.case-study-content.reverse .case-study-image {
  order: -1;
}

.case-study-text {
  padding: var(--spacing-lg) 0;
}

.case-study-title {
  font-size: 1.75rem;
  margin-bottom: var(--spacing-md);
}

.case-study-meta {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xl);
  font-weight: 500;
}

.case-study-overview {
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-xl);
  border-bottom: 1px solid var(--color-border);
}

.case-study-overview h4 {
  margin-bottom: var(--spacing-md);
}

.case-study-overview p {
  margin-bottom: 0;
  font-size: 0.95rem;
}

.case-study-metrics {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
  padding: var(--spacing-lg);
  background: var(--color-accent-light);
  border-radius: var(--border-radius);
}

.metric {
  text-align: center;
}

.metric-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: var(--spacing-xs);
}

.metric-label {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin-bottom: 0;
}

.case-study-link {
  display: inline-block;
  font-weight: 600;
  padding: var(--spacing-md) 0;
  border-bottom: 2px solid var(--color-accent);
  transition: all var(--transition-fast);
}

.case-study-link:hover {
  padding-right: var(--spacing-md);
  padding-left: var(--spacing-md);
  background: var(--color-accent-light);
}

.case-study-image {
  overflow: hidden;
  border-radius: var(--border-radius);
}

.case-study-image img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
  transition: transform var(--transition-normal);
}

.case-study-image:hover img {
  transform: scale(1.02);
}

@media (max-width: 1024px) {
  .case-study-content,
  .case-study-content.reverse {
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
  }

  .case-study-content.reverse .case-study-image {
    order: 0;
  }

  .case-study-metrics {
    grid-template-columns: 1fr;
  }

  .case-study {
    margin-bottom: var(--spacing-2xl);
  }
}

/* About Section */
.about {
  padding: var(--spacing-4xl) 0;
  background: #fafafa;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.about-content {
  max-width: 800px;
  margin: 0 auto;
}

.about-text p {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xl);
}

.about-text p:last-child {
  margin-bottom: 0;
}

@media (max-width: 768px) {
  .about-text p {
    font-size: 1rem;
  }
}

/* Contact Section */
.contact {
  padding: var(--spacing-4xl) 0;
  background: var(--color-bg);
}

.contact-content {
  max-width: 600px;
  margin: 0 auto;
  text-align: center;
}

.contact-intro {
  font-size: 1.1rem;
  margin-bottom: var(--spacing-2xl);
  color: var(--color-text-secondary);
}

.social-links {
  margin-top: var(--spacing-3xl);
}

.social-label {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-lg);
  display: block;
}

.social-list {
  display: flex;
  justify-content: center;
  gap: var(--spacing-2xl);
  flex-wrap: wrap;
}

.social-link {
  font-weight: 500;
  color: var(--color-accent);
  padding: var(--spacing-md);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
}

.social-link:hover {
  background: var(--color-accent-light);
  border-color: var(--color-accent);
  color: #0052a3;
}

/* Footer */
.footer {
  padding: var(--spacing-2xl) 0;
  background: #f5f5f5;
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

/* Scroll animations */
.fade-in {
  opacity: 0;
  animation: fadeInUp 0.6s ease-out forwards;
}

/* Mobile-first adjustments */
@media (max-width: 768px) {
  :root {
    --spacing-2xl: 32px;
    --spacing-3xl: 48px;
    --spacing-4xl: 64px;
  }

  .container {
    padding: 0 var(--spacing-md);
  }

  .nav-menu {
    gap: var(--spacing-lg);
  }

  .hero {
    padding: var(--spacing-2xl) 0;
  }

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

  .case-study-metrics {
    grid-template-columns: 1fr;
  }

  .contact-content .cta-button {
    width: 100%;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }
}

@media (max-width: 480px) {
  .nav-container {
    padding: 0 var(--spacing-md);
  }

  .nav-menu {
    gap: var(--spacing-lg);
    font-size: 0.85rem;
  }

  .hero-container {
    padding: 0 var(--spacing-md);
  }

  .section-title {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-2xl);
  }

  .case-study-link {
    font-size: 0.9rem;
  }

  .social-list {
    flex-direction: column;
    gap: var(--spacing-lg);
  }

  .social-link {
    display: block;
    width: 100%;
  }
}

/* Utilities */
.text-center {
  text-align: center;
}

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

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

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

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

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

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

.opacity-70 {
  opacity: 0.7;
}

.opacity-80 {
  opacity: 0.8;
}