/* ============================================
   CSS Variables & Theme
   ============================================ */
:root {
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --max-width: 720px;
  --radius: 12px;
  --transition: 0.3s ease;
}

[data-theme="dark"] {
  --bg: #0a0a0a;
  --bg-card: #141414;
  --bg-card-hover: #1a1a1a;
  --text: #e5e5e5;
  --text-muted: #888;
  --accent: #6ee7b7;
  --accent-dim: rgba(110, 231, 183, 0.1);
  --border: #222;
  --nav-bg: rgba(10, 10, 10, 0.85);
}

[data-theme="light"] {
  --bg: #fafafa;
  --bg-card: #ffffff;
  --bg-card-hover: #f5f5f5;
  --text: #1a1a1a;
  --text-muted: #666;
  --accent: #059669;
  --accent-dim: rgba(5, 150, 105, 0.08);
  --border: #e5e5e5;
  --nav-bg: rgba(250, 250, 250, 0.85);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  transition: background var(--transition), color var(--transition);
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  opacity: 0.8;
}

/* ============================================
   Navigation
   ============================================ */
header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--nav-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition), border-color var(--transition);
}

nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--text);
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-links a {
  color: var(--text-muted);
  font-size: 0.875rem;
  font-weight: 500;
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--text);
  opacity: 1;
}

.nav-links a.active {
  color: var(--accent);
}

.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px;
  cursor: pointer;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color var(--transition), border-color var(--transition);
}

.theme-toggle:hover {
  color: var(--text);
  border-color: var(--text-muted);
}

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

/* ============================================
   Main & Sections
   ============================================ */
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 80px 0 0;
}

.page-section {
  padding: 140px 0 0;
}

.page-section h1 {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 8px;
}

.section h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 8px;
  letter-spacing: -0.03em;
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 0.9375rem;
  margin-bottom: 24px;
}

.section-subtitle a {
  color: var(--accent);
}

/* ============================================
   Hero
   ============================================ */
.hero {
  padding: 140px 0 60px;
}

.hero-avatar {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--border);
  margin-bottom: 24px;
  transition: border-color var(--transition);
}

.hero-avatar:hover {
  border-color: var(--accent);
}

.hero-greeting {
  font-size: 1.125rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 12px;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.2;
  margin-bottom: 8px;
}

.highlight {
  background: linear-gradient(135deg, var(--accent), #34d399);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-tagline {
  font-size: 1.125rem;
  color: var(--text-muted);
  font-style: italic;
  margin-bottom: 16px;
}

.hero-intro {
  font-size: 1.0625rem;
  color: var(--text-muted);
  max-width: 520px;
  line-height: 1.7;
}

.social-links {
  display: flex;
  gap: 12px;
  margin-top: 28px;
}

.social-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  border: 1px solid var(--border);
  color: var(--text-muted);
  transition: all var(--transition);
}

.social-links a:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-dim);
  opacity: 1;
}

/* ============================================
   Cards
   ============================================ */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 16px;
  transition: background var(--transition), border-color var(--transition);
}

.card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.02em;
}

.card p {
  color: var(--text-muted);
  font-size: 0.9375rem;
}

.card p + p {
  margin-top: 12px;
}

/* About details */
.about-details {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

.detail-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.detail-label {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
}

.detail-value {
  font-size: 0.9375rem;
  color: var(--text);
}

/* ============================================
   Content Grid
   ============================================ */
.content-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}

.content-card {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: all var(--transition);
  color: var(--text);
}

.content-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent);
  transform: translateY(-2px);
  opacity: 1;
}

.content-type {
  display: inline-block;
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: var(--accent-dim);
  padding: 3px 8px;
  border-radius: 4px;
  margin-bottom: 10px;
}

.content-card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: 6px;
  letter-spacing: -0.02em;
}

.content-card p {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ============================================
   Footer
   ============================================ */
footer {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 60px 24px 40px;
  text-align: center;
}

footer p {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

/* Last updated */
.last-updated {
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-top: 8px;
  font-style: italic;
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 480px) {
  .nav-links {
    gap: 16px;
  }

  .about-details {
    grid-template-columns: 1fr;
  }

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

  .hero {
    padding: 120px 0 40px;
  }
}