:root {
  color-scheme: light;
  
  /* Core Colors */
  --page: #f8f8f6;            /* Refined warm sand/cream */
  --surface: #ffffff;         /* Pure white cards for premium crispness */
  --surface-2: #efeeea;       /* Subtle warm grey for code/breakouts */
  
  /* Typography Colors */
  --text-primary: #111214;    /* Premium soft ink black */
  --text-secondary: #4a4d52;  /* Charcoal slate for reading text */
  --text-muted: #7d828a;      /* Cool grey for sublabels/meta */
  --border: rgba(18, 19, 21, 0.08); /* Sophisticated thin border */
  
  /* Accent Colors */
  --accent: #1e40af;          /* Classic technical indigo-blue */
  --accent-hover: #1d4ed8;    /* Lighter hover blue */
  --accent-alpha: rgba(30, 64, 175, 0.08); /* Border glow overlay */
  
  /* Spacing Scale */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 40px;
  
  /* Shadows & Transitions */
  --shadow-sm: 0 1px 3px rgba(18, 19, 21, 0.02), 0 1px 2px rgba(18, 19, 21, 0.01);
  --shadow-md: 0 12px 28px rgba(18, 19, 21, 0.04), 0 4px 12px rgba(18, 19, 21, 0.01);
  --transition-smooth: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    
    /* Core Colors */
    --page: #08090b;          /* Ultra-deep obsidian slate */
    --surface: #111318;       /* Dark rich slate card */
    --surface-2: #191c24;     /* Dark breakout box */
    
    /* Typography Colors */
    --text-primary: #f3f4f6;    /* Crisp off-white */
    --text-secondary: #9ca3af;  /* Readable medium slate-gray */
    --text-muted: #6b7280;      /* Darker grey-blue */
    --border: rgba(243, 244, 246, 0.07);
    
    /* Accent Colors */
    --accent: #6366f1;          /* Sophisticated indigo-violet */
    --accent-hover: #818cf8;    /* Dynamic light violet */
    --accent-alpha: rgba(99, 102, 241, 0.15);
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 16px 36px rgba(0, 0, 0, 0.4);
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--page);
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.wrap {
  max-width: 720px; /* Typographically optimal line lengths (~65ch) */
  margin: 0 auto;
  padding: 72px 24px 96px;
  transition: var(--transition-smooth);
}

.hero {
  margin-bottom: 48px;
}

.eyebrow {
  margin: 0 0 16px;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.eyebrow a {
  color: var(--text-secondary);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: var(--transition-smooth);
}

.eyebrow a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

h1 {
  font-size: 2.2rem;
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -0.025em;
  margin: 0 0 16px;
  color: var(--text-primary);
}

.hero-sub {
  color: var(--text-secondary);
  font-size: 1.08rem;
  line-height: 1.6;
  max-width: 60ch;
  margin: 0;
}

.projects {
  display: flex;
  flex-direction: column;
  gap: 24px;
  margin-bottom: 48px;
}

.project-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 28px 32px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition-smooth);
}

/* Supporting project: present but visibly secondary to the two above it */
.project-card.supporting {
  background: transparent;
  box-shadow: none;
  padding: 22px 32px;
  opacity: 0.78;
}
.project-card.supporting .project-head h2 {
  font-size: 0.95em;
}

/* Hover/Focus card micro-interactions */
.project-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-alpha);
  box-shadow: var(--shadow-md);
}

.project-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 4px;
}

.project-head h2 {
  margin: 0;
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: var(--text-primary);
}

.project-link {
  font-size: 0.88rem;
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  border-bottom: 1.5px solid transparent;
  padding-bottom: 1px;
  transition: var(--transition-smooth);
}

.project-link:hover {
  color: var(--accent-hover);
  border-bottom-color: var(--accent-hover);
}

.project-link .arrow {
  display: inline-block;
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Arrow micro-interaction triggers on card hover OR link hover */
.project-card:hover .project-link .arrow,
.project-link:hover .arrow {
  transform: translateX(3px);
}

.project-tag {
  margin: 0 0 18px;
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.project-card p:not(.project-tag) {
  margin: 0 0 14px;
  color: var(--text-secondary);
  font-size: 0.96rem;
  line-height: 1.6;
}

.project-card p:last-child {
  margin-bottom: 0;
}

/* Re-designed Field Label pattern: clean, modern metadata signposts */
.field-label {
  color: var(--accent);
  font-weight: 700;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  display: inline-block;
  margin-right: 4px;
}

.ai-section {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 30px 32px;
  margin-bottom: 48px;
  position: relative;
  overflow: hidden;
}

/* Subtle editorial indicator to anchor the breakout section */
.ai-section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--accent);
  opacity: 0.65;
}

.ai-section h2 {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 16px;
  color: var(--text-primary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.ai-section p {
  color: var(--text-secondary);
  font-size: 0.96rem;
  line-height: 1.6;
  margin: 0 0 14px;
}

.ai-section p:last-child {
  margin-bottom: 0;
}

.site-footer {
  border-top: 1px solid var(--border);
  padding-top: 24px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.site-footer a {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid transparent;
  transition: var(--transition-smooth);
}

.site-footer a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* Keyboard Accessibility focus rings */
a:focus-visible {
  outline: 2px dashed var(--accent);
  outline-offset: 4px;
  border-radius: 2px;
}

.project-card:focus-within {
  outline: 2px dashed var(--accent);
  outline-offset: 4px;
}

/* Mobile responsive optimizations */
@media (max-width: 560px) {
  body {
    font-size: 15px;
  }
  
  .wrap {
    padding: 48px 16px 64px;
  }
  
  h1 {
    font-size: 1.65rem;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
  }
  
  .hero-sub {
    font-size: 0.98rem;
  }
  
  .projects {
    gap: 16px;
  }
  
  .project-card {
    padding: 22px 20px;
    border-radius: 10px;
  }
  
  /* Wrap header columns vertically on small viewports to prevent squishing */
  .project-head {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
    margin-bottom: 6px;
  }
  
  .project-head h2 {
    font-size: 1.2rem;
  }
  
  .project-tag {
    margin-bottom: 14px;
    font-size: 0.68rem;
  }
  
  .ai-section {
    padding: 24px 20px;
    border-radius: 10px;
    margin-bottom: 36px;
  }
}