/* ============================================
   Pixel43 — Design System
   Light & Dark Themes
   ============================================ */

:root {
  /* Shared colors */
  --color-green: #22c55e;
  --color-green-bright: #4ade80;
  
  /* Typography */
  --font-display: 'Roboto', system-ui, -apple-system, 'Segoe UI', sans-serif;
  --font-body: 'DM Sans', sans-serif;
  
  /* Spacing */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 5rem;
  --space-3xl: 8rem;
  
  /* Layout */
  --max-width: 1200px;
  --header-height: 80px;
  
  /* Transitions */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --duration: 0.4s;
}

/* Dark theme (default) */
[data-theme="dark"],
:root:not([data-theme="light"]) {
  --color-bg: #0a0a0a;
  --color-bg-elevated: #141414;
  --color-bg-card: #1a1a1a;
  --color-gray: #2a2a2a;
  --color-gray-light: #404040;
  --color-green-glow: rgba(74, 222, 128, 0.3);
  --color-text: #fafafa;
  --color-text-muted: #a3a3a3;
  --color-border: #2a2a2a;
  --color-shadow: rgba(0, 0, 0, 0.4);
  --color-header-scrolled: rgba(10, 10, 10, 0.9);
}

/* Light theme */
[data-theme="light"] {
  --color-bg: #fafafa;
  --color-bg-elevated: #f5f5f5;
  --color-bg-card: #ffffff;
  --color-gray: #e5e5e5;
  --color-gray-light: #d4d4d4;
  --color-green-glow: rgba(34, 197, 94, 0.25);
  --color-text: #171717;
  --color-text-muted: #525252;
  --color-border: #e5e5e5;
  --color-shadow: rgba(0, 0, 0, 0.08);
  --color-header-scrolled: rgba(250, 250, 250, 0.9);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  transition: background-color var(--duration) var(--ease-out), color var(--duration) var(--ease-out);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--duration) var(--ease-out);
}

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

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: var(--space-md) var(--space-lg);
  background: linear-gradient(to bottom, var(--color-bg) 0%, transparent 100%);
  transition: background var(--duration) var(--ease-out);
}

.header.scrolled {
  background: var(--color-header-scrolled);
  backdrop-filter: blur(12px);
}

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

.logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

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

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
  list-style: none;
}

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

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-muted);
}

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

.nav-cta {
  color: var(--color-green-bright) !important;
}

.nav-cta:hover {
  color: var(--color-green) !important;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: var(--duration) var(--ease-out);
}

/* Theme toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  padding: 0;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  cursor: pointer;
  color: var(--color-text-muted);
  transition: all var(--duration) var(--ease-out);
}

.theme-toggle:hover {
  color: var(--color-green-bright);
  border-color: var(--color-green);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
}

.theme-toggle .icon-sun {
  display: none;
}

.theme-toggle .icon-moon {
  display: block;
}

[data-theme="light"] .theme-toggle .icon-sun {
  display: block;
}

[data-theme="light"] .theme-toggle .icon-moon {
  display: none;
}

/* Hero */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: calc(var(--header-height) + var(--space-2xl)) var(--space-lg) var(--space-2xl);
  position: relative;
}

.hero-content {
  max-width: var(--max-width);
  margin: 0 auto;
  position: relative;
  z-index: 2;
}

.hero-label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-green-bright);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-md);
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.75rem, 7vw, 5rem);
  font-weight: 500;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-lg);
}

.text-gradient {
  background: linear-gradient(135deg, var(--color-green-bright), var(--color-green));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-description {
  font-size: 1.25rem;
  color: var(--color-text-muted);
  max-width: 480px;
  margin-bottom: var(--space-xl);
}

.hero-actions {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
}

.hero-visual {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: 50%;
  pointer-events: none;
}

.hero-grid {
  position: absolute;
  top: 50%;
  right: 10%;
  transform: translateY(-50%);
  width: 400px;
  height: 400px;
  background: 
    linear-gradient(var(--color-gray) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-gray) 1px, transparent 1px);
  background-size: 40px 40px;
  opacity: 0.3;
  border-radius: 50%;
  filter: blur(1px);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 1rem 1.75rem;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  border-radius: 8px;
  transition: all var(--duration) var(--ease-out);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--color-green-bright);
  color: #0a0a0a;
}

.btn-primary:hover {
  background: var(--color-green);
  color: var(--color-bg);
  box-shadow: 0 0 40px var(--color-green-glow);
}

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border: 2px solid var(--color-gray-light);
}

.btn-secondary:hover {
  border-color: var(--color-green-bright);
  color: var(--color-green-bright);
}

.btn-large {
  padding: 1.25rem 2rem;
  font-size: 1.125rem;
}

/* Section shared */
section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-3xl) var(--space-lg);
}

.section-header {
  margin-bottom: var(--space-2xl);
}

.section-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-green-bright);
  text-transform: uppercase;
  letter-spacing: 0.15em;
  margin-bottom: var(--space-sm);
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* Projects */
.projects {
  padding-top: var(--space-2xl);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

.project-card {
  background: var(--color-bg-card);
  border-radius: 12px;
  overflow: hidden;
  transition: transform var(--duration) var(--ease-out), box-shadow var(--duration) var(--ease-out);
}

.project-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 40px var(--color-shadow);
}

.project-card {
  transition: transform var(--duration) var(--ease-out), box-shadow var(--duration) var(--ease-out), background-color var(--duration) var(--ease-out);
}


.project-image {
  aspect-ratio: 16 / 10;
  overflow: hidden;
}

.project-placeholder {
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--color-gray) 0%, var(--color-bg-elevated) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: all var(--duration) var(--ease-out);
}

.project-card:hover .project-placeholder {
  background: linear-gradient(135deg, var(--color-gray-light) 0%, var(--color-gray) 100%);
  color: var(--color-green-bright);
}

.project-info {
  padding: var(--space-md);
}

.project-info h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 500;
  margin-bottom: var(--space-xs);
}

.project-info p {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* Services */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

.service-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: var(--space-xl);
  transition: border-color var(--duration) var(--ease-out), transform var(--duration) var(--ease-out), background-color var(--duration) var(--ease-out);
}

.service-card:hover {
  border-color: var(--color-green);
  transform: translateY(-2px);
}

.service-icon {
  width: 48px;
  height: 48px;
  margin-bottom: var(--space-md);
  color: var(--color-green-bright);
}

.service-icon svg {
  width: 100%;
  height: 100%;
}

.service-card h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 500;
  margin-bottom: var(--space-sm);
}

.service-card p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* About */
.about {
  background: var(--color-bg-elevated);
  transition: background-color var(--duration) var(--ease-out);
  border-radius: 24px;
  margin: 0 var(--space-lg) var(--space-3xl);
  padding: var(--space-2xl) var(--space-xl) !important;
}

.about-content {
  max-width: 700px;
}

.about-text {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  margin: var(--space-lg) 0 var(--space-xl);
  line-height: 1.7;
}

.about-stats {
  display: flex;
  gap: var(--space-2xl);
  flex-wrap: wrap;
}

.stat {
  display: flex;
  flex-direction: column;
}

.stat-number {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-green-bright);
  line-height: 1;
}

.stat-label {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-top: var(--space-xs);
}

/* Contact */
.contact {
  text-align: center;
  padding: var(--space-3xl) var(--space-lg) !important;
}

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

.contact-text {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  margin: var(--space-md) 0 var(--space-xl);
}

/* Footer */
.footer {
  border-top: 1px solid var(--color-border);
  transition: border-color var(--duration) var(--ease-out);
  padding: var(--space-xl) var(--space-lg);
}

.footer-content {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer-copy {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* Responsive */
@media (max-width: 1024px) {
  .projects-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .services-grid {
    grid-template-columns: 1fr;
  }
  
  .hero-visual {
    width: 30%;
  }
  
  .hero-grid {
    width: 250px;
    height: 250px;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .nav-actions {
    display: flex;
  }
  
  .nav-toggle {
    display: flex;
  }
  
  .hero-visual {
    display: none;
  }
  
  .projects-grid {
    grid-template-columns: 1fr;
  }
  
  .hero-actions {
    flex-direction: column;
  }
  
  .btn {
    width: 100%;
  }
  
  .about-stats {
    flex-direction: column;
    gap: var(--space-lg);
  }
  
  .footer-content {
    flex-direction: column;
    text-align: center;
  }
}

/* Mobile menu (when toggled) */
.nav-links.open {
  display: flex;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  flex-direction: column;
  justify-content: center;
  gap: var(--space-xl);
  background: var(--color-bg);
  z-index: 99;
  font-size: 1.5rem;
}