/* ==========================================================================
   Design System — Custom Properties
   ========================================================================== */

:root {
  /* Colors — Light Theme */
  --bg-primary:       #ffffff;
  --bg-secondary:     #f8f9fc;
  --bg-card:          #ffffff;
  --bg-card-hover:    #f8f9fc;
  --accent:           #2563eb;
  --accent-glow:      rgba(37, 99, 235, 0.08);
  --text-primary:     #111827;
  --text-secondary:   #6b7280;
  --border-subtle:    rgba(0, 0, 0, 0.08);
  --gradient-nav:     #ffffff;
  --gradient-hero:    linear-gradient(180deg, #f0f4ff 0%, #ffffff 100%);

  /* Typography */
  --font-body: 'Inter', sans-serif;
  --font-heading: 'Space Grotesk', sans-serif;

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

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
}

/* ==========================================================================
   Base / Reset
   ========================================================================== */

*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a:hover {
  color: #1d4ed8;
}

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

/* ==========================================================================
   Typography
   ========================================================================== */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
  margin-top: 0;
}

h1 { font-size: 3rem; }
h2 { font-size: 2.25rem; }
h3 { font-size: 1.5rem; }

.text-gradient {
  background: linear-gradient(135deg, #111827 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

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

/* ==========================================================================
   Navbar
   ========================================================================== */

.site-nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--gradient-nav);
  border-bottom: 1px solid var(--border-subtle);
  transition: box-shadow var(--transition-base);
}

.site-nav.scrolled {
  box-shadow: 0 1px 12px rgba(0, 0, 0, 0.06);
}

.site-nav .navbar-brand {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary) !important;
  letter-spacing: -0.02em;
}

.site-nav .nav-link {
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary) !important;
  padding: 0.5rem 1rem !important;
  border-radius: 6px;
  transition: color var(--transition-fast), background var(--transition-fast);
  position: relative;
}

.site-nav .nav-link:hover,
.site-nav .nav-link.active {
  color: var(--text-primary) !important;
  background: rgba(0, 0, 0, 0.04);
}

.site-nav .nav-link.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 20px;
  height: 2px;
  background: var(--accent);
  border-radius: 1px;
}

.site-nav .social-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 8px;
  transition: background var(--transition-fast);
}

.site-nav .social-icon:hover {
  background: rgba(0, 0, 0, 0.06);
}

.site-nav .social-icon svg {
  width: 20px;
  height: 20px;
  fill: var(--text-secondary);
  transition: fill var(--transition-fast);
}

.site-nav .social-icon:hover svg {
  fill: var(--text-primary);
}

/* Mobile toggler for light theme */
.site-nav .navbar-toggler {
  border-color: var(--border-subtle);
}

.site-nav .navbar-toggler-icon {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba(17, 24, 39, 0.75)' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}

/* ==========================================================================
   Sections
   ========================================================================== */

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

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

/* ==========================================================================
   Hero Section
   ========================================================================== */

.hero {
  background: var(--gradient-hero);
  padding: var(--space-xl) 0 var(--space-lg);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 50%, var(--accent-glow) 0%, transparent 50%);
  pointer-events: none;
}

.hero-portrait {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid rgba(37, 99, 235, 0.2);
  box-shadow: 0 8px 30px rgba(37, 99, 235, 0.1);
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.hero-subtitle {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 500;
  color: var(--accent);
  margin-bottom: 1rem;
}

.hero-tagline {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 1.5rem;
  max-width: 520px;
}

/* Hero CTAs */
.hero-ctas {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2rem;
}

/* Credential Badges */
.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.85rem;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-primary);
  border: 1px solid var(--border-subtle);
  border-radius: 20px;
}

.hero-badge svg {
  width: 14px;
  height: 14px;
  fill: var(--accent);
  flex-shrink: 0;
}

/* ==========================================================================
   Buttons
   ========================================================================== */

.btn-accent {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 2rem;
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
  background: var(--accent);
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: transform var(--transition-fast), box-shadow var(--transition-base);
  text-decoration: none;
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(37, 99, 235, 0.2);
  color: #fff;
}

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

.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 2rem;
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  color: var(--accent);
  background: transparent;
  border: 2px solid var(--accent);
  border-radius: 8px;
  cursor: pointer;
  transition: transform var(--transition-fast), background var(--transition-base), color var(--transition-base);
  text-decoration: none;
}

.btn-outline:hover {
  transform: translateY(-2px);
  background: var(--accent);
  color: #fff;
}

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

/* ==========================================================================
   Capability Cards (What I Do)
   ========================================================================== */

.card-capability {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  padding: 2rem;
  height: 100%;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.card-capability:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.06);
}

.card-capability .capability-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-glow);
  border-radius: 12px;
  margin-bottom: 1.25rem;
}

.card-capability .capability-icon svg {
  width: 24px;
  height: 24px;
  fill: var(--accent);
}

.card-capability h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.card-capability p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 0;
}

/* ==========================================================================
   About Section
   ========================================================================== */

.bio-section {
  max-width: 720px;
  margin: 0 auto;
  padding: var(--space-lg) var(--space-sm);
}

.bio-section p {
  font-size: 1.125rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

/* ==========================================================================
   Experience Timeline
   ========================================================================== */

.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border-subtle);
}

.timeline-item {
  position: relative;
  padding-bottom: 2rem;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -2rem;
  top: 0.35rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-primary);
  transform: translateX(-50%);
  margin-left: 1px;
}

.timeline-company {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.15rem;
}

.timeline-role {
  color: var(--accent);
  font-size: 0.95rem;
  font-weight: 500;
  margin-bottom: 0.15rem;
}

.timeline-date {
  color: var(--text-secondary);
  font-size: 0.85rem;
  margin-bottom: 0.35rem;
}

.timeline-summary {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.5;
}

/* ==========================================================================
   Divider
   ========================================================================== */

.divider {
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  border: none;
  margin: var(--space-sm) auto;
  max-width: 200px;
  opacity: 0.3;
}

/* ==========================================================================
   Section Header
   ========================================================================== */

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

.section-header h2 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

/* ==========================================================================
   Project Cards
   ========================================================================== */

.card-project {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  overflow: hidden;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  height: 100%;
  display: flex;
  flex-direction: column;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08), 0 1px 3px rgba(0, 0, 0, 0.06);
  border: 1px solid rgba(0, 0, 0, 0.1);
}

.card-project:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

.card-project .card-img-wrapper {
  overflow: hidden;
  aspect-ratio: 16 / 10;
}

.card-project .card-img-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-base);
}

.card-project:hover .card-img-wrapper img {
  transform: scale(1.02);
}

.card-project .card-body {
  padding: 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card-project .card-title {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.card-project .card-text {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
  flex: 1;
}

.card-project a {
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.card-project a:hover {
  color: inherit;
}

/* Tech Tags */
.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1rem;
}

.tech-tag {
  display: inline-block;
  padding: 0.2rem 0.65rem;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-glow);
  border-radius: 20px;
  border: 1px solid rgba(37, 99, 235, 0.12);
}

/* ==========================================================================
   Education / Credential Cards
   ========================================================================== */

.card-credential {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  padding: 1.5rem;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.card-credential:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.card-credential .credential-logo {
  width: 80px;
  height: 80px;
  object-fit: contain;
  flex-shrink: 0;
  border-radius: 12px;
  background: var(--bg-secondary);
  padding: 0.5rem;
}

.card-credential .credential-info h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.card-credential .credential-info .credential-school {
  color: var(--accent);
  font-weight: 500;
  font-size: 0.95rem;
}

.card-credential .credential-info .credential-location {
  color: var(--text-secondary);
  font-size: 0.85rem;
}

.card-credential .credential-info .credential-year {
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* ==========================================================================
   Contact Cards
   ========================================================================== */

.card-contact {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  padding: 2rem;
  text-align: center;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.card-contact:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.08);
}

.card-contact a {
  text-decoration: none;
  color: inherit;
}

.card-contact .contact-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-glow);
  border-radius: 12px;
}

.card-contact .contact-icon svg {
  width: 24px;
  height: 24px;
  fill: var(--accent);
}

.card-contact .contact-label {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.card-contact .contact-value {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* ==========================================================================
   Footer
   ========================================================================== */

.site-footer {
  border-top: 1px solid var(--border-subtle);
  padding: var(--space-md) 0;
  background: var(--bg-secondary);
}

.site-footer .footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.site-footer .footer-text {
  color: var(--text-secondary);
  font-size: 0.85rem;
  margin: 0;
}

.site-footer .footer-socials {
  display: flex;
  gap: 0.75rem;
}

.site-footer .footer-socials a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  transition: border-color var(--transition-fast), background var(--transition-fast);
}

.site-footer .footer-socials a:hover {
  border-color: rgba(37, 99, 235, 0.2);
  background: var(--accent-glow);
}

.site-footer .footer-socials svg {
  width: 18px;
  height: 18px;
  fill: var(--text-secondary);
}

.site-footer .footer-socials a:hover svg {
  fill: var(--text-primary);
}

/* ==========================================================================
   Fade-in Animation
   ========================================================================== */

.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

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

@media (max-width: 767.98px) {
  .hero {
    padding: var(--space-lg) 0 var(--space-md);
    text-align: center;
  }

  .hero-portrait {
    width: 150px;
    height: 150px;
    margin: 0 auto var(--space-md);
  }

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

  .hero-tagline {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-ctas {
    justify-content: center;
  }

  .hero-badges {
    justify-content: center;
  }

  .section-header h2 {
    font-size: 2rem;
  }

  .card-credential {
    flex-direction: column;
    text-align: center;
  }

  .timeline {
    padding-left: 1.5rem;
  }

  .site-footer .footer-content {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 575.98px) {
  .hero-title {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.75rem;
  }
}