/* ===== DESIGN TOKENS ===== */
:root {
  /* Type Scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);
  --text-3xl: clamp(2.5rem, 1rem + 4vw, 5rem);

  /* Spacing */
  --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;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;

  /* Fonts */
  --font-display: 'Cabinet Grotesk', 'Inter', sans-serif;
  --font-body: 'Satoshi', 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', 'Consolas', monospace;
}

/* ===== LIGHT MODE (default) ===== */
:root,
[data-theme='light'] {
  --color-bg: #FAFAF8;
  --color-surface: #FFFFFF;
  --color-surface-2: #F5F5F3;
  --color-border: #E2E0DC;
  --color-divider: #ECEAE6;
  --color-text: #1A1A1A;
  --color-text-muted: #6B6B6B;
  --color-text-faint: #A3A3A3;
  --color-primary: #2563EB;
  --color-primary-hover: #1D4ED8;
  --color-primary-active: #1E40AF;
  --color-primary-highlight: #DBEAFE;
  --color-accent: #0EA5E9;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 12px 32px rgba(0,0,0,0.12);
}

/* ===== DARK MODE ===== */
[data-theme='dark'] {
  --color-bg: #0F0F0F;
  --color-surface: #1A1A1A;
  --color-surface-2: #242424;
  --color-border: #333333;
  --color-divider: #2A2A2A;
  --color-text: #E5E5E5;
  --color-text-muted: #9CA3AF;
  --color-text-faint: #6B7280;
  --color-primary: #60A5FA;
  --color-primary-hover: #93C5FD;
  --color-primary-active: #3B82F6;
  --color-primary-highlight: #1E3A5F;
  --color-accent: #38BDF8;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
  --shadow-lg: 0 12px 32px rgba(0,0,0,0.5);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg: #0F0F0F;
    --color-surface: #1A1A1A;
    --color-surface-2: #242424;
    --color-border: #333333;
    --color-divider: #2A2A2A;
    --color-text: #E5E5E5;
    --color-text-muted: #9CA3AF;
    --color-text-faint: #6B7280;
    --color-primary: #60A5FA;
    --color-primary-hover: #93C5FD;
    --color-primary-active: #3B82F6;
    --color-primary-highlight: #1E3A5F;
    --color-accent: #38BDF8;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
    --shadow-lg: 0 12px 32px rgba(0,0,0,0.5);
  }
}

/* ===== GLOBAL STYLES ===== */
a {
  color: var(--color-primary);
  text-decoration: none;
}
a:hover {
  color: var(--color-primary-hover);
}

/* ===== HEADER / NAV ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: oklch(from var(--color-bg) l c h / 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-divider);
  transition: box-shadow 0.3s ease;
}
.header--scrolled {
  box-shadow: var(--shadow-sm);
}
.header-inner {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding: var(--space-4) var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--text-lg);
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}
.logo span {
  color: var(--color-primary);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  list-style: none;
}
.nav-links a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  font-weight: 500;
  position: relative;
  padding-bottom: 2px;
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width 0.25s ease;
}
.nav-links a:hover {
  color: var(--color-text);
}
.nav-links a:hover::after {
  width: 100%;
}
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  cursor: pointer;
}
.theme-toggle:hover {
  background: var(--color-surface-2);
  color: var(--color-text);
}
.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
}
.mobile-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all 0.3s ease;
}
.mobile-nav {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100dvh;
  background: var(--color-bg);
  z-index: 100;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-8);
}
.mobile-nav.active {
  display: flex;
}
.mobile-nav a {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  color: var(--color-text);
  text-decoration: none;
  font-weight: 600;
}
.mobile-nav-close {
  position: absolute;
  top: var(--space-4);
  right: var(--space-6);
  font-size: var(--text-xl);
  color: var(--color-text);
  background: none;
  border: none;
  cursor: pointer;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .mobile-toggle {
    display: flex;
  }
}

/* ===== HERO ===== */
.hero {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding: clamp(var(--space-12), 8vw, var(--space-32)) var(--space-6);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: center;
  min-height: 80vh;
}
.hero-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--color-primary-highlight);
  color: var(--color-primary);
  font-size: var(--text-xs);
  font-weight: 600;
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  width: fit-content;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.hero-badge .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}
.hero h1 {
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 800;
  color: var(--color-text);
  letter-spacing: -0.03em;
  line-height: 1.05;
}
.hero h1 .highlight {
  color: var(--color-primary);
}
.hero-subtitle {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  max-width: 50ch;
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-lg);
  font-size: var(--text-sm);
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition-interactive);
  cursor: pointer;
}
.btn-primary {
  background: var(--color-primary);
  color: #fff;
}
.btn-primary:hover {
  background: var(--color-primary-hover);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.btn-secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}
.btn-secondary:hover {
  background: var(--color-surface-2);
  color: var(--color-text);
  transform: translateY(-1px);
}
.hero-stats {
  display: flex;
  gap: var(--space-8);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-divider);
}
.stat-item {
  display: flex;
  flex-direction: column;
}
.stat-number {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-text);
  letter-spacing: -0.02em;
}
.stat-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.hero-image-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
}
.hero-image-container {
  position: relative;
  width: 380px;
  height: 460px;
}
.hero-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}
.hero-image-decoration {
  position: absolute;
  inset: -12px;
  border: 2px solid var(--color-primary);
  border-radius: calc(var(--radius-xl) + 12px);
  opacity: 0.2;
  z-index: -1;
}
.hero-image-dot {
  position: absolute;
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--color-primary);
  opacity: 0.1;
  z-index: -1;
}
.hero-image-dot--1 {
  top: -20px;
  right: -20px;
}
.hero-image-dot--2 {
  bottom: -16px;
  left: -16px;
  width: 48px;
  height: 48px;
}

@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
    text-align: center;
    min-height: auto;
    padding-top: var(--space-12);
    padding-bottom: var(--space-12);
  }
  .hero-content {
    align-items: center;
    order: 2;
  }
  .hero-badge {
    margin-inline: auto;
  }
  .hero-subtitle {
    margin-inline: auto;
  }
  .hero-actions {
    justify-content: center;
  }
  .hero-stats {
    justify-content: center;
  }
  .hero-image-wrapper {
    order: 1;
  }
  .hero-image-container {
    width: 260px;
    height: 320px;
  }
}

/* ===== SECTIONS ===== */
.section {
  padding: clamp(var(--space-12), 6vw, var(--space-24)) var(--space-6);
}
.section-alt {
  background: var(--color-surface-2);
}
.section-inner {
  max-width: var(--content-wide);
  margin-inline: auto;
}
.section-header {
  margin-bottom: var(--space-12);
}
.section-label {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-3);
}
.section-title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 800;
  color: var(--color-text);
  letter-spacing: -0.02em;
}
.section-subtitle {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  margin-top: var(--space-3);
  max-width: 55ch;
}

/* ===== ABOUT ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: start;
}
.about-text {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}
.about-text p {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.7;
}
.about-details {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}
.detail-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
}
.detail-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--color-primary-highlight);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.detail-info h4 {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}
.detail-info p {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}
@media (max-width: 768px) {
  .about-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== PROJECTS ===== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(340px, 100%), 1fr));
  gap: var(--space-6);
}
.project-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  transition: all 0.25s ease;
  position: relative;
  overflow: hidden;
}
.project-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}
.project-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.project-type {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: var(--color-primary-highlight);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
}
.project-icon {
  color: var(--color-text-faint);
}
.project-card h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
}
.project-card p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.65;
  flex: 1;
}
.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}
.project-tag {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  background: var(--color-surface-2);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-weight: 500;
}
.project-award {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-xs);
  font-weight: 700;
  color: #D97706;
  margin-top: var(--space-1);
}

/* ===== SKILLS ===== */
.skills-categories {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(280px, 100%), 1fr));
  gap: var(--space-6);
}
.skill-category {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
}
.skill-category-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-5);
}
.skill-category-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--color-primary-highlight);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
}
.skill-category h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
}
.skill-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.skill-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-2) 0;
}
.skill-name {
  font-size: var(--text-sm);
  color: var(--color-text);
  font-weight: 500;
}
.skill-level {
  display: flex;
  gap: 3px;
}
.skill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-divider);
}
.skill-dot.filled {
  background: var(--color-primary);
}

/* ===== EXPERIENCE ===== */
.experience-item {
  display: flex;
  gap: var(--space-6);
  padding: var(--space-6) 0;
  border-bottom: 1px solid var(--color-divider);
}
.experience-item:last-child {
  border-bottom: none;
}
.experience-date {
  min-width: 140px;
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  font-weight: 500;
  padding-top: var(--space-1);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.experience-content h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}
.experience-content h4 {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: var(--space-2);
}
.experience-content p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.65;
}
@media (max-width: 600px) {
  .experience-item {
    flex-direction: column;
    gap: var(--space-2);
  }
}

/* ===== CONTACT ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-8);
  align-items: start;
}
.contact-text {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}
.contact-text p {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.7;
}
.contact-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}
.contact-link {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-4) var(--space-5);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  text-decoration: none;
  color: var(--color-text);
  transition: all 0.25s ease;
}
.contact-link:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  color: var(--color-text);
}
.contact-link-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--color-primary-highlight);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.contact-link-info h4 {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
}
.contact-link-info p {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}
@media (max-width: 768px) {
  .contact-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== FOOTER ===== */
.footer {
  border-top: 1px solid var(--color-divider);
  padding: var(--space-8) var(--space-6);
}
.footer-inner {
  max-width: var(--content-wide);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
}
.footer-text {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}
.footer-links {
  display: flex;
  gap: var(--space-4);
}
.footer-links a {
  color: var(--color-text-muted);
  transition: color var(--transition-interactive);
}
.footer-links a:hover {
  color: var(--color-primary);
}

/* ===== SCROLL REVEAL ===== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}