/* =====================================================
   PREMIUM AI ENGINEER PORTFOLIO - Complete Design System
   Linear/Vercel-level polish + Material 3 discipline
   ===================================================== */

/* -------------------------------------------------------
   1. DESIGN TOKENS
   ------------------------------------------------------- */
:root {
  /* Colors - Premium Dark Theme */
  --bg-primary: #0a0a0a;
  --bg-secondary: #0f0f0f;
  --bg-elevated: #141414;
  --bg-surface: #1a1a1a;
  --bg-surface-hover: #222222;
  
  --text-primary: #ffffff;
  --text-secondary: #a0a0a0;
  --text-muted: #666666;
  
  --accent-primary: #00d4aa;
  --accent-primary-light: #00f0c0;
  --accent-primary-dim: rgba(0, 212, 170, 0.15);
  --accent-secondary: #7c3aed;
  --accent-tertiary: #61afef;
  
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-medium: rgba(255, 255, 255, 0.10);
  --border-accent: rgba(0, 212, 170, 0.3);
  
  /* Spacing - Tighter rhythm */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.6);
  --shadow-xl: 0 16px 64px rgba(0, 0, 0, 0.7);
  --shadow-glow: 0 0 40px rgba(0, 212, 170, 0.12);
  
  /* Motion */
  --duration-fast: 120ms;
  --duration-normal: 200ms;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
}

/* -------------------------------------------------------
   2. GLOBAL RESET & BASE
   ------------------------------------------------------- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text-secondary);
  background: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* -------------------------------------------------------
   3. TYPOGRAPHY
   ------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  color: var(--text-primary);
  letter-spacing: -0.025em;
}

h1 { font-size: clamp(2.5rem, 6vw, 4.5rem); }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: clamp(1.5rem, 2.5vw, 2rem); }
h4 { font-size: 1.25rem; }

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

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

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

/* -------------------------------------------------------
   4. LAYOUT
   ------------------------------------------------------- */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-8);
}

.section {
  padding: var(--space-12) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-10);
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--space-3);
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-muted);
}

/* -------------------------------------------------------
   5. HEADER
   ------------------------------------------------------- */
.premium-header {
  background: rgba(10, 10, 10, 0.95);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-8);
  max-width: 1400px;
  margin: 0 auto;
}

.header-left {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.brand-name {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-primary);
}

.brand-badge {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--accent-primary);
  background: var(--accent-primary-dim);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
}

.primary-menu {
  display: flex;
  gap: var(--space-2);
  list-style: none;
  margin: 0;
  padding: 0;
}

.primary-menu a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  transition: all var(--duration-fast) var(--ease-out);
}

.primary-menu a:hover,
.primary-menu a.active {
  color: var(--text-primary);
  background: var(--bg-surface);
}

.primary-menu a.active {
  color: var(--accent-primary);
}

/* -------------------------------------------------------
   6. HERO SECTION
   ------------------------------------------------------- */
.hero-section {
  padding: var(--space-16) 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--bg-surface);
  border: 1px solid var(--border-medium);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-6);
}

.badge-dot {
  width: 8px;
  height: 8px;
  background: var(--accent-primary);
  border-radius: var(--radius-full);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: var(--space-6);
}

.hero-title .accent {
  color: var(--accent-primary);
  display: block;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
}

.hero-description {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: var(--space-8);
  max-width: 540px;
}

.proof-block {
  max-width: 620px;
  margin-bottom: var(--space-8);
  padding: var(--space-5);
  background: linear-gradient(135deg, rgba(0, 212, 170, 0.10), rgba(124, 58, 237, 0.08));
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-glow);
}

.proof-kicker {
  display: inline-flex;
  align-items: center;
  margin-bottom: var(--space-3);
  color: var(--accent-primary);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.proof-list {
  display: grid;
  gap: var(--space-3);
  margin: 0;
  padding: 0;
  list-style: none;
}

.proof-list li {
  position: relative;
  padding-left: var(--space-5);
  color: var(--text-secondary);
  font-size: 0.925rem;
  line-height: 1.55;
}

.proof-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 8px;
  height: 8px;
  border-radius: 999px;
  background: var(--accent-primary);
  box-shadow: 0 0 16px rgba(0, 212, 170, 0.55);
}

.proof-list strong {
  color: var(--text-primary);
}

.hero-cta {
  display: flex;
  gap: var(--space-4);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-4) var(--space-6);
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: 1rem;
  transition: all var(--duration-fast) var(--ease-out);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--accent-primary);
  color: var(--bg-primary);
}

.btn-primary:hover {
  background: var(--accent-primary-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.btn-secondary {
  background: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-medium);
}

.btn-secondary:hover {
  background: var(--bg-surface-hover);
  border-color: var(--border-accent);
}

/* AI System Card */
.hero-visual {
  display: flex;
  justify-content: center;
}

.ai-system-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  max-width: 500px;
  width: 100%;
}

.ai-card-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-subtle);
}

.ai-card-dots {
  display: flex;
  gap: var(--space-2);
}

.ai-card-dots span {
  width: 12px;
  height: 12px;
  border-radius: var(--radius-full);
  background: var(--border-subtle);
}

.ai-card-title {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.ai-card-content {
  padding: var(--space-6);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.6;
}

.code-line {
  margin-bottom: var(--space-1);
}

.code-keyword { color: var(--accent-secondary); }
.code-class { color: var(--accent-tertiary); }
.code-function { color: var(--accent-primary); }
.code-string { color: #98c379; }
.code-bool { color: #d19a66; }
.code-comment { color: var(--text-muted); font-style: italic; }

.ai-card-footer {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
}

.node-indicator {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.node-indicator.active {
  color: var(--accent-primary);
}

/* -------------------------------------------------------
   7. ABOUT SECTION
   ------------------------------------------------------- */
.about-content {
  max-width: 800px;
  margin: 0 auto;
}

.about-text p {
  margin-bottom: var(--space-6);
  font-size: 1.125rem;
  line-height: 1.7;
}

/* -------------------------------------------------------
   8. SKILLS SECTION
   ------------------------------------------------------- */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: var(--space-6);
}

.skill-category {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  transition: all var(--duration-normal) var(--ease-out);
}

.skill-category:hover {
  border-color: var(--border-accent);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.skill-category-header {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-bottom: var(--space-5);
}

.skill-category-icon {
  width: 48px;
  height: 48px;
  background: var(--accent-primary-dim);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.875rem;
  color: var(--accent-primary);
}

.skill-category-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-primary);
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.skill-tag {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  transition: all var(--duration-fast) var(--ease-out);
}

.skill-tag:hover {
  border-color: var(--border-accent);
  color: var(--accent-primary);
}

/* -------------------------------------------------------
   9. PORTFOLIO SECTION
   ------------------------------------------------------- */
.portfolio-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: var(--space-6);
}

.portfolio-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: all var(--duration-normal) var(--ease-out);
  cursor: pointer;
}

.portfolio-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
  border-color: var(--border-accent);
}

.portfolio-thumbnail {
  height: 180px;
  position: relative;
  overflow: hidden;
}

.portfolio-image-bg {
  position: absolute;
  inset: 0;
  opacity: 0.3;
}

.gradient-hermes {
  background: linear-gradient(135deg, #00d4aa 0%, #7c3aed 100%);
}

.gradient-health {
  background: linear-gradient(135deg, #00d4aa 0%, #61afef 100%);
}

.gradient-finance {
  background: linear-gradient(135deg, #7c3aed 0%, #00d4aa 100%);
}

.gradient-automation {
  background: linear-gradient(135deg, #61afef 0%, #7c3aed 100%);
}

.gradient-enterprise {
  background: linear-gradient(135deg, #00d4aa 0%, #61afef 100%);
}

.gradient-realestate {
  background: linear-gradient(135deg, #7c3aed 0%, #00d4aa 100%);
}

.gradient-communication {
  background: radial-gradient(circle at 25% 20%, rgba(255,255,255,0.22), transparent 28%),
    linear-gradient(135deg, #7c3aed 0%, #2563eb 48%, #00d4aa 100%);
}

.portfolio-thumbnail-icon {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 3rem;
  z-index: 1;
}

.portfolio-content {
  padding: var(--space-5);
}

.portfolio-category {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent-primary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-2);
}

.portfolio-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
}

.portfolio-description {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: var(--space-4);
  line-height: 1.6;
}

.portfolio-tech {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.tech-badge {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* -------------------------------------------------------
   10. CONTACT SECTION
   ------------------------------------------------------- */
.contact-layout {
  display: flex;
  justify-content: center;
}

.contact-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-2xl);
  padding: var(--space-10);
  text-align: center;
  max-width: 600px;
}

.contact-avatar {
  width: 120px;
  height: 120px;
  margin: 0 auto var(--space-6);
  background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
}

.avatar-initials {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--bg-primary);
}

.contact-name {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.contact-title {
  font-size: 1rem;
  color: var(--accent-primary);
  margin-bottom: var(--space-4);
}

.contact-description {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: var(--space-6);
  line-height: 1.7;
}

.contact-email {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--accent-primary);
  color: var(--bg-primary);
  padding: var(--space-3) var(--space-5);
  border-radius: var(--radius-lg);
  font-weight: 600;
  margin-bottom: var(--space-6);
  transition: all var(--duration-fast) var(--ease-out);
}

.contact-email:hover {
  background: var(--accent-primary-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.contact-social {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
}

.social-link {
  width: 48px;
  height: 48px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: all var(--duration-fast) var(--ease-out);
}

.social-link:hover {
  background: var(--accent-primary-dim);
  border-color: var(--border-accent);
  color: var(--accent-primary);
  transform: translateY(-4px);
}

/* -------------------------------------------------------
   11. FOOTER
   ------------------------------------------------------- */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-subtle);
  padding: var(--space-8) 0;
  text-align: center;
}

.footer-content p {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin: 0;
}

/* -------------------------------------------------------
   12. RESPONSIVE DESIGN
   ------------------------------------------------------- */
@media (max-width: 1024px) {
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .hero-visual {
    order: -1;
  }
  
  .hero-description {
    margin-left: auto;
    margin-right: auto;
  }
  
  .hero-stats {
    justify-content: center;
  }
  
  .hero-cta {
    justify-content: center;
  }
}

@media (max-width: 768px) {
  .header-center {
    display: none;
  }
  
  .hero-title {
    font-size: 2.5rem;
    line-height: 1.15;
    margin-bottom: var(--space-4);
  }
  
  .hero-subtitle {
    margin-bottom: var(--space-4);
  }
  
  .hero-description {
    margin-bottom: var(--space-6);
  }
  
  .hero-stats {
    flex-direction: column;
    gap: var(--space-4);
  }
  
  .hero-cta {
    flex-direction: column;
  }
  
  .skills-grid {
    grid-template-columns: 1fr;
  }
  
  .portfolio-grid {
    grid-template-columns: 1fr;
  }
  
  .contact-card {
    padding: var(--space-6);
  }
}

/* -------------------------------------------------------
   13. MOTION & ANIMATIONS
   ------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* -------------------------------------------------------
   14. ACCESSIBILITY
   ------------------------------------------------------- */
:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

/* -------------------------------------------------------
   15. POPUP MOBILE MENU
   ------------------------------------------------------- */
.popup-mobile-menu {
  position: fixed;
  top: 0;
  left: -320px;
  width: 320px;
  height: 100vh;
  background: var(--bg-secondary);
  z-index: 2000;
  transition: left var(--duration-normal) var(--ease-out);
  padding: var(--space-6);
  border-right: 1px solid var(--border-subtle);
  opacity: 0;
  pointer-events: none;
}

.popup-mobile-menu.active {
  left: 0;
  opacity: 1;
  pointer-events: auto;
}

.menu-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-6);
}

.close-button {
  display: flex;
}

.close-menu-activation {
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: var(--space-2);
}

/* -------------------------------------------------------
   16. UTILITIES
   ------------------------------------------------------- */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }

.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

/* -------------------------------------------------------
   17. HEADER FIXES - Hide leaked close-menu on header
   ------------------------------------------------------- */
.header-right .close-menu {
  display: none !important;
}

/* Ensure hamberger menu is visible on mobile */
.header-right .hamberger-menu {
  display: block !important;
}

/* -------------------------------------------------------
   18. MOBILE TIGHTENING - Tighter spacing on small screens
   ------------------------------------------------------- */
@media (max-width: 768px) {
  .skill-category {
    padding: var(--space-5);
  }
  
  .portfolio-card {
    margin-bottom: var(--space-4);
  }
  
  .contact-card {
    padding: var(--space-6);
  }
}

/* Hotfix: restored AI refresh must not leak inactive mobile controls/nav */
.close-menu {
  display: none !important;
}

.popup-mobile-menu {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateX(100%);
}

.popup-mobile-menu.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(0);
}

@media (max-width: 1024px) {
  .hero-content {
    display: flex;
    flex-direction: column;
  }
  .hero-text {
    order: 1;
  }
  .hero-visual {
    order: 2;
  }
}