@layer reset, base, components, utilities;

@layer reset {
  *, *::before, *::after {
    box-sizing: border-box;
  }
  
  * {
    margin: 0;
    padding: 0;
  }
  
  html {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
  }
  
  img, picture, video, canvas, svg {
    display: block;
    max-width: 100%;
  }
  
  input, button, textarea, select {
    font: inherit;
  }
  
  button {
    border: none;
    background: none;
    cursor: pointer;
  }
  
  ul, ol {
    list-style: none;
  }
}

@layer base {
  :root {
    color-scheme: dark light;
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
    --font-serif: 'Fraunces', 'Georgia', ui-serif, serif;
    
    /* Colors - Dark with enhanced vibrancy */
    --bg: oklch(16% 0.025 250);
    --bg-elevated: oklch(19% 0.025 250);
    --bg-overlay: oklch(14% 0.03 250 / 0.85);
    --fg: oklch(96% 0.008 250);
    --fg-muted: oklch(72% 0.018 250);
    --fg-subtle: oklch(62% 0.02 250);
    --accent-cyan: oklch(80% 0.18 195);
    --accent-indigo: oklch(65% 0.24 270);
    --accent-pink: oklch(72% 0.20 350);
    --accent-gradient: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-indigo) 50%, var(--accent-pink) 100%);
    --accent-gradient-soft: linear-gradient(135deg, oklch(80% 0.18 195 / 0.15), oklch(65% 0.24 270 / 0.15));
    --border: oklch(38% 0.02 250 / 0.35);
    --border-subtle: oklch(35% 0.02 250 / 0.18);
    --grid-line: oklch(50% 0.01 250 / 0.08);
    
    /* Enhanced shadows */
    --shadow-sm: 0 2px 4px 0 oklch(0% 0 0 / 0.08), 0 1px 2px 0 oklch(0% 0 0 / 0.04);
    --shadow-md: 0 6px 12px -2px oklch(0% 0 0 / 0.12), 0 3px 6px -3px oklch(0% 0 0 / 0.08);
    --shadow-lg: 0 12px 24px -4px oklch(0% 0 0 / 0.18), 0 6px 12px -6px oklch(0% 0 0 / 0.12);
    --shadow-xl: 0 24px 48px -8px oklch(0% 0 0 / 0.24), 0 12px 24px -12px oklch(0% 0 0 / 0.16);
    --shadow-glow: 0 0 32px -8px var(--accent-cyan);
    
    /* Spacing */
    --section-gap: clamp(4rem, 10vw, 7rem);
    --content-max: 70ch;
    --container-padding: clamp(1.25rem, 5vw, 2.5rem);
    
    /* Enhanced radius */
    --radius-sm: 0.625rem;
    --radius-md: 0.875rem;
    --radius-lg: 1.25rem;
    --radius-xl: 1.75rem;
    --radius-2xl: 2.25rem;
    --radius-full: 624.9375rem;
    
    /* Focus */
    --focus-ring: 0 0 0 3px oklch(80% 0.18 195 / 0.5);
    --focus-ring-offset: 0 0 0 2px var(--bg), 0 0 0 5px oklch(80% 0.18 195 / 0.5);
    
    /* Safe areas */
    --safe-top: env(safe-area-inset-top, 0);
    --safe-bottom: env(safe-area-inset-bottom, 0);
    --safe-left: env(safe-area-inset-left, 0);
    --safe-right: env(safe-area-inset-right, 0);
  }

  [data-theme='light'] {
    --bg: oklch(98% 0.008 240);
    --bg-elevated: oklch(100% 0 0);
    --bg-overlay: oklch(100% 0 0 / 0.97);
    --fg: oklch(22% 0.025 250);
    --fg-muted: oklch(42% 0.025 250);
    --fg-subtle: oklch(52% 0.025 250);
    --accent-cyan: oklch(58% 0.22 200);
    --accent-indigo: oklch(52% 0.24 270);
    --accent-pink: oklch(60% 0.22 350);
    --accent-gradient: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-indigo) 50%, var(--accent-pink) 100%);
    --accent-gradient-soft: linear-gradient(135deg, oklch(58% 0.22 200 / 0.12), oklch(52% 0.24 270 / 0.12));
    --border: oklch(85% 0.01 250 / 0.65);
    --border-subtle: oklch(90% 0.008 250 / 0.45);
    --grid-line: oklch(78% 0.01 240 / 0.1);
    --focus-ring: 0 0 0 3px oklch(58% 0.22 200 / 0.4);
    --shadow-sm: 0 2px 4px 0 oklch(0% 0 0 / 0.1);
    --shadow-md: 0 6px 12px -2px oklch(0% 0 0 / 0.14), 0 3px 6px -3px oklch(0% 0 0 / 0.1);
    --shadow-lg: 0 12px 24px -4px oklch(0% 0 0 / 0.18), 0 6px 12px -6px oklch(0% 0 0 / 0.12);
    --shadow-xl: 0 24px 48px -8px oklch(0% 0 0 / 0.22), 0 12px 24px -12px oklch(0% 0 0 / 0.16);
    --shadow-glow: 0 0 32px -8px oklch(58% 0.22 200 / 0.3);
  }

  @supports (color: color(display-p3 1 1 1)) {
    @media (color-gamut: p3) {
      :root {
        --accent-cyan: color(display-p3 0.28 0.78 0.98);
        --accent-indigo: color(display-p3 0.42 0.45 0.96);
        --accent-pink: color(display-p3 0.88 0.42 0.68);
      }
    }
  }

  html {
    scroll-behavior: smooth;
    scroll-padding-top: 5rem;
  }

  @media (prefers-reduced-motion: reduce) {
    html {
      scroll-behavior: auto;
    }
    
    * {
      animation-duration: 0.01ms !important;
      animation-iteration-count: 1 !important;
      transition-duration: 0.01ms !important;
    }
  }

  body {
    font-family: var(--font-sans);
    font-size: clamp(1rem, 0.95rem + 0.3vw, 1.125rem);
    line-height: 1.7;
    background: var(--bg);
    color: var(--fg);
    min-block-size: 100vh;
    min-block-size: 100dvh;
    position: relative;
    overflow-x: clip;
    padding-block-start: var(--safe-top);
  }

  /* Enhanced grid with subtle animation */
  body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image: 
      linear-gradient(0deg, transparent 96%, var(--grid-line) 98%),
      linear-gradient(90deg, transparent 96%, var(--grid-line) 98%);
    background-size: 4rem 4rem;
    opacity: 0.6;
    pointer-events: none;
    z-index: -2;
    animation: gridFloat 60s ease-in-out infinite;
  }

  @keyframes gridFloat {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(8px, 8px); }
  }

  /* Enhanced gradient overlays */
  body::after {
    content: '';
    position: fixed;
    inset: 0;
    background: 
      radial-gradient(ellipse 90% 60% at 50% 0%, oklch(65% 0.24 270 / 0.22), transparent 65%),
      radial-gradient(ellipse 70% 50% at 80% 100%, oklch(72% 0.20 350 / 0.18), transparent 55%),
      radial-gradient(ellipse 70% 50% at 20% 100%, oklch(80% 0.18 195 / 0.16), transparent 55%);
    pointer-events: none;
    z-index: -1;
    animation: gradientShift 20s ease-in-out infinite;
  }

  @keyframes gradientShift {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.85; }
  }

  h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-serif);
    line-height: 1.1;
    font-weight: 700;
    color: var(--fg);
    text-wrap: balance;
    letter-spacing: -0.02em;
  }

  h1 {
    font-size: clamp(2.25rem, 4vw + 0.5rem, 4.25rem);
    font-weight: 800;
    letter-spacing: -0.025em;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }

  h2 {
    font-size: clamp(1.75rem, 3vw + 0.5rem, 2.75rem);
    letter-spacing: -0.02em;
  }

  h3 {
    font-size: clamp(1.375rem, 2.25vw + 0.5rem, 1.875rem);
    letter-spacing: -0.015em;
  }

  p {
    max-inline-size: var(--content-max);
    text-wrap: pretty;
  }

  a {
    color: var(--accent-cyan);
    text-decoration: none;
    position: relative;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  }

  a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-gradient);
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  }

  a:hover::after {
    width: 100%;
  }

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

  a:focus-visible {
    outline: none;
    border-radius: 0.25rem;
    box-shadow: var(--focus-ring);
  }

  button:focus-visible,
  [role="tab"]:focus-visible {
    outline: none;
    box-shadow: var(--focus-ring-offset);
  }

  ::selection {
    background: oklch(80% 0.18 195 / 0.35);
    color: var(--fg);
  }
}

@layer components {
  .skip-link {
    position: absolute;
    inset-inline-start: -625rem;
    inset-block-start: var(--safe-top);
    background: var(--accent-gradient);
    color: white;
    padding-block: 0.875rem;
    padding-inline: 1.5rem;
    border-radius: var(--radius-full);
    font-weight: 700;
    z-index: 9999;
    box-shadow: var(--shadow-xl);
  }

  .skip-link:focus {
    inset-inline-start: 1rem;
    inset-block-start: calc(1rem + var(--safe-top));
  }

  #progress-bar {
    position: fixed;
    inset-block-start: 0;
    inset-inline-start: 0;
    block-size: 0.3rem;
    inline-size: 0;
    background: var(--accent-gradient);
    z-index: 9998;
    transition: inline-size 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 0 16px var(--accent-cyan);
  }

  .hero {
    position: relative;
    padding-block: clamp(5rem, 14vh, 8rem) clamp(4rem, 10vh, 6rem);
    padding-inline: var(--container-padding);
    overflow: clip;
    min-block-size: clamp(600px, 80vh, 900px);
    display: grid;
    align-items: center;
  }

  .hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background: 
      radial-gradient(ellipse 100% 70% at 50% 0%, oklch(25% 0.1 270 / 0.5), transparent),
      var(--bg);
    z-index: -1;
  }

  .hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, 
      oklch(16% 0.03 250 / 0.97) 0%, 
      oklch(16% 0.03 260 / 0.75) 50%,
      oklch(16% 0.03 250 / 0.92) 100%
    );
    z-index: -1;
    backdrop-filter: blur(2px);
  }

  [data-theme='light'] .hero::before {
    background: 
      radial-gradient(ellipse 100% 70% at 50% 0%, oklch(78% 0.1 240 / 0.3), transparent),
      var(--bg);
  }

  [data-theme='light'] .hero-overlay {
    background: linear-gradient(135deg, 
      oklch(97% 0.01 240 / 0.88) 0%, 
      oklch(99% 0.005 250 / 0.65) 50%,
      oklch(97% 0.01 240 / 0.92) 100%
    );
  }

  [data-theme='light'] body::after {
    background: 
      radial-gradient(ellipse 90% 60% at 50% 0%, oklch(72% 0.18 200 / 0.18), transparent 65%),
      radial-gradient(ellipse 70% 50% at 80% 100%, oklch(68% 0.18 270 / 0.15), transparent 55%),
      radial-gradient(ellipse 70% 50% at 20% 100%, oklch(75% 0.15 350 / 0.14), transparent 55%);
  }

  .hero-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.25rem;
    flex-wrap: wrap;
  }

  .hero-header .step-chip {
    margin-block-end: 0;
  }

  .hero-controls {
    display: inline-flex;
    align-items: center;
    justify-content: flex-end;
    gap: 0.875rem;
    flex-wrap: wrap;
    padding: 0.625rem 1rem;
    background: var(--bg-overlay);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-full);
    backdrop-filter: blur(20px) saturate(180%);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
  }

  .hero-controls:hover {
    box-shadow: var(--shadow-lg);
    border-color: var(--border);
  }

  .theme-toggle {
    min-block-size: 2.75rem;
    min-inline-size: 2.75rem;
    padding: 0.625rem 1rem;
    background: var(--bg-overlay);
    backdrop-filter: blur(16px) saturate(180%);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-full);
    color: var(--fg);
    display: inline-flex;
    align-items: center;
    gap: 0.625rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  .theme-toggle::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  .theme-toggle:hover::before {
    opacity: 1;
  }

  .theme-toggle:hover {
    transform: translateY(-3px) scale(1.02);
    background: var(--bg-elevated);
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-lg), var(--shadow-glow);
  }

  .theme-toggle:active {
    transform: translateY(-1px) scale(0.98);
  }

  .theme-toggle svg {
    inline-size: 1.375rem;
    block-size: 1.375rem;
    position: relative;
    z-index: 1;
  }

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

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

  .hero-layout {
    display: grid;
    gap: clamp(2rem, 5vw, 3.5rem);
  }

  .hero-main {
    display: grid;
    gap: 1.5rem;
  }

  .hero-aside {
    display: grid;
    gap: 1.5rem;
    align-content: start;
  }

  .content-container {
    inline-size: min(1280px, 100%);
    margin-inline: auto;
    padding-inline: var(--container-padding);
  }

  .hero-content {
    display: flex;
    flex-direction: column;
    gap: 1.75rem;
    max-inline-size: 60rem;
  }

  .eyebrow {
    text-transform: uppercase;
    letter-spacing: 0.16em;
    font-size: 0.8125rem;
    font-weight: 700;
    color: var(--accent-indigo);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: oklch(65% 0.24 270 / 0.15);
    border-radius: var(--radius-full);
    width: fit-content;
  }

  .eyebrow::before {
    content: '';
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent-gradient);
    animation: pulse 2s ease-in-out infinite;
  }

  @keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.7; transform: scale(0.95); }
  }

  .title-period {
    display: inline-block;
    color: var(--fg-muted);
    font-weight: 600;
  }

  .hero-subtitle {
    font-size: clamp(1.25rem, 1.75vw, 1.5rem);
    color: var(--fg-muted);
    font-weight: 500;
    line-height: 1.55;
  }

  .hero-narrative {
    color: var(--fg);
    line-height: 1.75;
    font-size: clamp(1.0625rem, 1.2vw, 1.125rem);
  }

  .hero-metric {
    display: inline-flex;
    flex-direction: column;
    gap: 0.625rem;
    padding: 1.5rem 2rem;
    background: var(--bg-overlay);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    max-inline-size: 24rem;
    backdrop-filter: blur(16px) saturate(160%);
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  }

  .hero-metric::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.4s ease;
  }

  .hero-metric:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl), 0 0 40px oklch(80% 0.18 195 / 0.2);
    border-color: var(--accent-cyan);
  }

  .hero-metric:hover::before {
    opacity: 1;
  }

  .metric-label {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    font-weight: 600;
    color: var(--fg-subtle);
    position: relative;
    z-index: 1;
  }

  .metric-value {
    font-size: clamp(2.25rem, 4.5vw, 2.75rem);
    font-family: var(--font-serif);
    font-weight: 800;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-variant-numeric: tabular-nums;
    position: relative;
    z-index: 1;
  }

  .hero-aside {
    padding: clamp(1.75rem, 3.5vw, 2.5rem);
    background: var(--bg-overlay);
    border: 1px solid var(--border);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
    backdrop-filter: blur(20px) saturate(160%);
    position: relative;
    overflow: hidden;
  }

  .hero-aside::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, oklch(80% 0.18 195 / 0.2), transparent 70%);
    pointer-events: none;
  }

  .hero-aside .hero-metric {
    inline-size: 100%;
    max-inline-size: none;
  }

  .hero-aside .kpi-group {
    width: 100%;
    position: relative;
    z-index: 1;
  }

  .hero-aside .kpi-chip {
    flex: 1 1 calc(50% - 0.875rem);
    justify-content: space-between;
  }

  @media (width >= 62rem) {
    .hero-layout {
      grid-template-columns: minmax(0, 1fr) minmax(280px, 1fr);
    }
  }

  @media (width <= 48rem) {
    .hero-controls {
      width: auto;
      justify-content: flex-end;
      padding: 0.625rem 0.75rem;
      gap: 0.625rem;
      margin-inline-start: auto;
    }

    .hero-aside {
      padding: 1.5rem;
    }

    .hero-aside .kpi-chip {
      flex: 1 1 100%;
    }
  }

  .kpi-group {
    display: flex;
    flex-wrap: wrap;
    gap: 0.875rem;
    margin-block: 0;
  }

  .kpi-chip {
    display: inline-flex;
    align-items: center;
    gap: 0.625rem;
    padding: 0.75rem 1.375rem;
    min-block-size: 3rem;
    border-radius: var(--radius-full);
    background: var(--bg-overlay);
    backdrop-filter: blur(12px) saturate(150%);
    border: 1px solid var(--border-subtle);
    font-size: 0.9375rem;
    line-height: 1.5;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  .kpi-chip::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  .kpi-chip:hover {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-md), 0 0 20px oklch(80% 0.18 195 / 0.15);
    transform: translateY(-2px);
  }

  .kpi-chip:hover::before {
    opacity: 1;
  }

  .kpi-label {
    font-weight: 600;
    color: var(--fg);
    position: relative;
    z-index: 1;
  }

  .kpi-value {
    min-inline-size: 3.5rem;
    font-variant-numeric: tabular-nums;
    font-weight: 600;
    position: relative;
    z-index: 1;
  }

  .kpi-divider {
    color: var(--fg-subtle);
    position: relative;
    z-index: 1;
  }

  .kpi-period,
  .kpi-source {
    color: var(--fg-muted);
    font-size: 0.875rem;
    position: relative;
    z-index: 1;
  }

  .hero-cta-row {
    display: flex;
    flex-wrap: wrap;
    gap: 1.125rem;
    margin-block-start: 0.75rem;
  }

  .hero-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.625rem;
    min-inline-size: 12rem;
    min-block-size: 3.25rem;
    padding: 0.875rem 2rem;
    border-radius: var(--radius-full);
    font-weight: 700;
    font-size: 1rem;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  .hero-cta::before {
    content: '';
    position: absolute;
    inset: 0;
    background: white;
    opacity: 0;
    transition: opacity 0.35s ease;
  }

  .hero-cta svg {
    inline-size: 1.125rem;
    block-size: 1.125rem;
    transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    z-index: 1;
  }

  .hero-cta span {
    position: relative;
    z-index: 1;
  }

  .hero-cta-primary {
    background: var(--accent-gradient);
    color: white;
    border: none;
    box-shadow: var(--shadow-lg), 0 0 30px oklch(80% 0.18 195 / 0.3);
  }

  .hero-cta-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl), 0 0 50px oklch(80% 0.18 195 / 0.5);
  }

  .hero-cta-primary:hover::before {
    opacity: 0.15;
  }

  .hero-cta-primary:hover svg {
    transform: translateX(4px);
  }

  .hero-cta-secondary {
    background: var(--bg-elevated);
    border: 1.5px solid var(--border);
    color: var(--fg);
  }

  .hero-cta-secondary::after {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.35s ease;
  }

  .hero-cta-secondary:hover {
    transform: translateY(-3px);
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-lg), 0 0 30px oklch(80% 0.18 195 / 0.2);
  }

  .hero-cta-secondary:hover::after {
    opacity: 1;
  }

  .mini-toc {
    position: sticky;
    inset-block-start: var(--safe-top);
    background: var(--bg-overlay);
    backdrop-filter: blur(24px) saturate(180%);
    border-block-end: 1px solid var(--border);
    z-index: 100;
    margin-block-end: calc(var(--section-gap) * 0.6);
    box-shadow: 0 4px 16px oklch(0% 0 0 / 0.1);
  }

  .mini-toc-inner {
    inline-size: min(1280px, 100%);
    margin-inline: auto;
    padding-inline: var(--container-padding);
  }

  .mini-toc ul {
    display: flex;
    flex-wrap: wrap;
    gap: 0.625rem;
    padding-block: 1rem;
  }

  .mini-toc a {
    color: var(--fg-muted);
    font-size: 0.9375rem;
    font-weight: 600;
    padding: 0.625rem 1.25rem;
    min-block-size: 2.5rem;
    border-radius: var(--radius-full);
    display: inline-flex;
    align-items: center;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  .mini-toc a::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  .mini-toc a span {
    position: relative;
    z-index: 1;
  }

  .mini-toc a:hover {
    color: var(--fg);
    transform: translateY(-2px);
  }

  .mini-toc a:hover::before {
    opacity: 1;
  }

  .study-section {
    padding-block: calc(var(--section-gap) * 0.7);
    scroll-margin-block-start: 6rem;
  }

  .section-heading {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-block-end: 2.5rem;
  }

  .section-subtitle {
    color: var(--fg-muted);
    font-size: 1.125rem;
    font-weight: 500;
    line-height: 1.6;
  }

  .step-chip {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    inline-size: 3rem;
    block-size: 3rem;
    border-radius: var(--radius-full);
    background: var(--accent-gradient);
    color: white;
    font-weight: 800;
    font-size: 1.125rem;
    margin-block-end: 1.75rem;
    box-shadow: var(--shadow-lg), 0 0 30px oklch(65% 0.24 270 / 0.3);
    animation: stepChipFloat 3s ease-in-out infinite;
  }

  @keyframes stepChipFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-4px); }
  }

  .grounding-stat {
    color: var(--fg-muted);
    margin-block-start: 1.75rem;
    font-weight: 500;
    font-style: italic;
    padding: 1rem 1.5rem;
    background: var(--accent-gradient-soft);
    border-left: 3px solid var(--accent-cyan);
    border-radius: var(--radius-md);
  }

  .method-bullets {
    display: grid;
    gap: 1.5rem;
  }

  .method-bullets li {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 1.5rem;
    padding: 2rem;
    background: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(12px);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  .method-bullets li::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.4s ease;
  }

  .method-bullets li:hover {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-xl), 0 0 40px oklch(80% 0.18 195 / 0.15);
    transform: translateY(-4px);
  }

  .method-bullets li:hover::before {
    opacity: 1;
  }

  .method-icon {
    display: grid;
    place-items: center;
    inline-size: 4rem;
    block-size: 4rem;
    border-radius: var(--radius-lg);
    background: var(--accent-gradient);
    color: white;
    flex-shrink: 0;
    box-shadow: var(--shadow-md), 0 0 20px oklch(65% 0.24 270 / 0.3);
    position: relative;
    z-index: 1;
  }

  .method-icon svg {
    inline-size: 1.75rem;
    block-size: 1.75rem;
  }

  .method-bullets h3 {
    font-size: 1.25rem;
    margin-block-end: 0.625rem;
    position: relative;
    z-index: 1;
  }

  .method-bullets p {
    color: var(--fg-muted);
    line-height: 1.7;
    position: relative;
    z-index: 1;
  }

  .insight-grid {
    display: grid;
    gap: 2.5rem;
    inline-size: min(1280px, 100%);
    margin-inline: auto;
    padding-inline: var(--container-padding);
  }

  .insight-card {
    background: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-2xl);
    padding: 2.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.75rem;
    backdrop-filter: blur(16px);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  .insight-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.4s ease;
  }

  .insight-card:hover {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-xl), 0 0 60px oklch(80% 0.18 195 / 0.2);
    transform: translateY(-6px);
  }

  .insight-card:hover::before {
    opacity: 1;
  }

  .insight-card header {
    position: relative;
    z-index: 1;
  }

  .insight-card header h3 {
    font-size: 1.375rem;
  }

  .chart-figure {
    display: grid;
    gap: 1.5rem;
    position: relative;
    z-index: 1;
  }

  .chart-tabs {
    display: flex;
    gap: 0.625rem;
    flex-wrap: wrap;
    padding: 0.5rem;
    background: var(--bg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-subtle);
  }

  .chart-tab {
    border-radius: var(--radius-full);
    border: 1px solid transparent;
    background: transparent;
    color: var(--fg-muted);
    padding: 0.75rem 1.5rem;
    min-inline-size: 8rem;
    min-block-size: 3rem;
    font-weight: 600;
    font-size: 0.9375rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  .chart-tab::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient);
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  .chart-tab span {
    position: relative;
    z-index: 1;
  }

  .chart-tab:hover {
    color: var(--fg);
    transform: translateY(-2px);
  }

  .chart-tab:hover::before {
    opacity: 0.15;
  }

  .chart-tab.is-active {
    color: white;
    border-color: transparent;
    box-shadow: var(--shadow-md), 0 0 20px oklch(80% 0.18 195 / 0.3);
  }

  .chart-tab.is-active::before {
    opacity: 1;
  }

  .chart-frame {
    position: relative;
    inline-size: 100%;
    min-block-size: 22rem;
    background: oklch(from var(--bg) calc(l - 0.015) c h);
    border-radius: var(--radius-xl);
    border: 1px solid var(--border-subtle);
    padding: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: inset 0 2px 8px oklch(0% 0 0 / 0.05);
  }

  .chart-frame canvas {
    inline-size: 100% !important;
    block-size: 100% !important;
  }

  .chart-frame.multiples {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
    gap: 1.25rem;
    padding: 2rem;
    min-block-size: auto;
  }

  .chart-frame.multiples canvas {
    min-block-size: 14rem;
    block-size: 14rem !important;
    background: var(--bg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-subtle);
    padding: 1rem;
    transition: all 0.3s ease;
  }

  .chart-frame.multiples canvas:hover {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-md), 0 0 20px oklch(80% 0.18 195 / 0.15);
    transform: scale(1.02);
  }

  .chart-caption {
    display: grid;
    gap: 0.75rem;
    font-size: 0.9375rem;
  }

  .chart-note {
    color: var(--fg-muted);
    line-height: 1.7;
    padding: 1rem 1.25rem;
    background: var(--accent-gradient-soft);
    border-radius: var(--radius-md);
    border-left: 3px solid var(--accent-cyan);
  }

  .chart-footnote {
    font-size: 0.875rem;
    color: var(--fg-subtle);
    padding-inline-start: 1.25rem;
  }

  .appendix-link {
    color: var(--accent-cyan);
    text-decoration: underline;
    text-decoration-style: dotted;
    text-underline-offset: 0.25em;
    text-decoration-thickness: 1.5px;
    transition: all 0.3s ease;
    font-weight: 500;
  }

  .appendix-link:hover {
    text-decoration-style: solid;
    color: var(--accent-indigo);
  }

  .bullet-list {
    display: grid;
    gap: 1.125rem;
    padding-inline-start: 1.75rem;
    list-style: none;
    color: var(--fg-muted);
  }

  .bullet-list li {
    padding-inline-start: 0.75rem;
    line-height: 1.75;
    position: relative;
  }

  .bullet-list li::before {
    content: '';
    position: absolute;
    left: -1.5rem;
    top: 0.6em;
    width: 8px;
    height: 8px;
    background: var(--accent-gradient);
    border-radius: 50%;
    box-shadow: 0 0 10px oklch(80% 0.18 195 / 0.5);
  }

  .sources-table-wrapper {
    margin-block-start: 2.5rem;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    background: var(--bg-elevated);
    overflow-x: auto;
    overflow-y: hidden;
    box-shadow: var(--shadow-lg);
  }

  .sources-table {
    inline-size: 100%;
    border-collapse: collapse;
    font-size: 0.9375rem;
    min-inline-size: 45rem;
  }

  .sources-table th,
  .sources-table td {
    padding: 1.125rem 1.5rem;
    border-block-end: 1px solid var(--border-subtle);
    text-align: start;
  }

  .sources-table th {
    font-weight: 700;
    color: var(--fg);
    background: oklch(from var(--bg-elevated) calc(l - 0.015) c h);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-size: 0.8125rem;
  }

  .sources-table td {
    color: var(--fg-muted);
  }

  .sources-table tbody tr {
    transition: background 0.3s ease;
  }

  .sources-table tbody tr:hover {
    background: var(--accent-gradient-soft);
  }

  .sources-table tbody tr:last-child th,
  .sources-table tbody tr:last-child td {
    border-block-end: none;
  }

  .sources-table a {
    font-weight: 600;
  }

  .site-footer {
    padding-block: 4rem;
    padding-inline: var(--container-padding);
    padding-block-end: calc(4rem + var(--safe-bottom));
    text-align: center;
    color: var(--fg-muted);
    font-size: 0.9375rem;
    border-block-start: 1px solid var(--border);
    margin-block-start: var(--section-gap);
    position: relative;
  }

  .site-footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 300px;
    height: 1px;
    background: var(--accent-gradient);
    box-shadow: 0 0 20px var(--accent-cyan);
  }

  /* Data Transparency Layer */
  .transparency-section {
    position: relative;
    margin-top: var(--section-gap);
    border-radius: var(--radius-2xl);
    border: 1px solid var(--border);
    background:
      radial-gradient(circle at 10% 20%, oklch(65% 0.24 270 / 0.3), transparent 60%),
      radial-gradient(circle at 80% 0%, oklch(80% 0.18 195 / 0.25), transparent 65%),
      var(--bg-elevated);
    overflow: hidden;
    box-shadow: var(--shadow-xl);
  }

  .transparency-section::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, oklch(80% 0.18 195 / 0.12), transparent 45%);
    pointer-events: none;
  }

  .transparency-section .content-container {
    position: relative;
    padding-block: clamp(2.5rem, 6vw, 4rem);
  }

  .transparency-header {
    display: flex;
    flex-wrap: wrap;
    gap: 2rem;
    align-items: center;
    justify-content: space-between;
  }

  .transparency-heading {
    max-width: 50ch;
    display: grid;
    gap: 1rem;
  }

  .transparency-chip {
    align-self: start;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1.125rem;
    font-size: 0.8125rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    border-radius: var(--radius-full);
    background: var(--accent-gradient);
    color: white;
    font-weight: 700;
    box-shadow: var(--shadow-md), 0 0 20px oklch(80% 0.18 195 / 0.3);
  }

  .transparency-heading h2 {
    font-family: var(--font-serif);
    font-size: clamp(2rem, 2vw + 0.5rem, 2.75rem);
  }

  .transparency-intro {
    color: var(--fg-muted);
    font-size: 1.0625rem;
    line-height: 1.75;
  }

  .transparency-content {
    margin-top: clamp(2rem, 5vw, 2.5rem);
  }

  .transparency-overview {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.25rem;
    margin-top: clamp(2rem, 5vw, 2.5rem);
  }

  .overview-card {
    position: relative;
    padding: 1.5rem 1.5rem;
    border-radius: var(--radius-xl);
    border: 1px solid var(--border);
    background: var(--bg);
    box-shadow: var(--shadow-md);
    display: grid;
    gap: 0.5rem;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    overflow: hidden;
  }

  .overview-card::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.4s ease;
  }

  .overview-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl), 0 0 40px oklch(80% 0.18 195 / 0.2);
    border-color: var(--accent-cyan);
  }

  .overview-card:hover::after {
    opacity: 1;
  }

  .overview-card span {
    position: relative;
    z-index: 1;
  }

  .overview-metric {
    font-family: var(--font-serif);
    font-size: 1.75rem;
    font-weight: 800;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }

  .overview-label {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--fg-subtle);
    font-weight: 600;
  }

  .transparency-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: clamp(2.5rem, 6vw, 3rem);
  }

  .transparency-card {
    position: relative;
    background: var(--bg);
    padding: 2rem;
    border-radius: var(--radius-xl);
    border: 1px solid var(--border-subtle);
    box-shadow: var(--shadow-md);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    overflow: hidden;
  }

  .transparency-card::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.4s ease;
    pointer-events: none;
  }

  .transparency-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl), 0 0 50px oklch(80% 0.18 195 / 0.2);
    border-color: var(--accent-cyan);
  }

  .transparency-card:hover::before {
    opacity: 1;
  }

  .transparency-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
    color: var(--fg);
    position: relative;
    z-index: 1;
  }

  .transparency-card ul,
  .transparency-card ol {
    list-style: none;
    margin: 0;
    padding: 0;
    position: relative;
    z-index: 1;
  }

  .transparency-card li {
    padding: 0.5rem 0;
    color: var(--fg-muted);
    font-size: 0.9375rem;
    line-height: 1.7;
  }

  .transparency-card ul li::before {
    content: '';
    display: inline-block;
    width: 6px;
    height: 6px;
    background: var(--accent-gradient);
    border-radius: 50%;
    margin-right: 0.75rem;
    box-shadow: 0 0 8px oklch(80% 0.18 195 / 0.5);
  }

  .transparency-timeline ol {
    counter-reset: step-counter;
  }

  .transparency-timeline ol li {
    counter-increment: step-counter;
    position: relative;
    padding-left: 3.5rem;
    margin-bottom: 0.75rem;
  }

  .transparency-timeline ol li::before {
    content: counter(step-counter);
    position: absolute;
    left: 0;
    top: 0.25rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.25rem;
    height: 2.25rem;
    border-radius: var(--radius-full);
    background: var(--accent-gradient);
    color: white;
    font-size: 0.875rem;
    font-weight: 700;
    box-shadow: var(--shadow-md), 0 0 20px oklch(80% 0.18 195 / 0.4);
  }

  .transparency-timeline ol li::after {
    content: '';
    position: absolute;
    left: 1.125rem;
    top: 2.25rem;
    bottom: -1rem;
    width: 2px;
    background: linear-gradient(to bottom, var(--accent-cyan), transparent);
  }

  .transparency-timeline ol li:last-child::after {
    display: none;
  }

  .transparency-highlight {
    border: 1.5px solid var(--accent-cyan);
    background:
      linear-gradient(135deg, oklch(from var(--accent-cyan) l c h / 0.2), transparent 70%),
      var(--bg);
    box-shadow: var(--shadow-lg), 0 0 40px oklch(80% 0.18 195 / 0.15);
  }

  .transparency-card p {
    margin: 0.75rem 0;
    color: var(--fg-muted);
    font-size: 0.9375rem;
    line-height: 1.75;
    position: relative;
    z-index: 1;
  }

  .challenge-outcome {
    margin-top: 1.25rem;
    padding: 1rem 1.25rem;
    background: var(--accent-gradient-soft);
    border-left: 4px solid var(--accent-cyan);
    border-radius: var(--radius-md);
    color: var(--fg);
    box-shadow: inset 0 1px 2px oklch(0% 0 0 / 0.05);
  }

  /* Footer Signature */
  .footer-signature {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
    margin-bottom: 2.5rem;
  }

  .signature-animation {
    max-width: 450px;
    width: 100%;
    height: auto;
  }

  .signature-path {
    animation: drawSignature 3.5s ease-in-out forwards;
    filter: drop-shadow(0 0 8px var(--accent-cyan));
  }

  @keyframes drawSignature {
    to {
      stroke-dashoffset: 0;
    }
  }

  .signature-text {
    text-align: center;
    font-size: 1.1875rem;
    line-height: 1.7;
    color: var(--fg);
    margin: 0;
  }

  .signature-brand {
    font-family: var(--font-serif);
    font-weight: 800;
    font-size: 1.5rem;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }

  .signature-name {
    font-weight: 700;
  }

  .signature-tagline {
    display: block;
    margin-top: 0.375rem;
    font-style: italic;
    color: var(--fg-muted);
    font-size: 1rem;
  }

  .footer-legal {
    text-align: center;
    color: var(--fg-subtle);
    font-size: 0.875rem;
    margin: 0;
  }
}

@layer utilities {
  @media (width <= 64rem) {
    .hero-controls {
      position: static;
      justify-content: flex-end;
      margin-block: 1.75rem 0;
      margin-inline: var(--container-padding);
    }

    .chart-frame {
      min-block-size: 18rem;
    }

    .chart-frame.multiples {
      grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
    }
  }

  @media (width <= 48rem) {
    body {
      --section-gap: clamp(2.5rem, 6vw, 3.5rem);
    }

    h1 {
      font-size: clamp(2.25rem, 8vw, 3.5rem);
    }

    .hero {
      min-block-size: auto;
      padding-block: clamp(4rem, 14vw, 5rem) clamp(3rem, 16vw, 4.5rem);
    }

    .hero-content {
      gap: 1.5rem;
      max-inline-size: none;
    }

    .hero-header {
      align-items: flex-start;
    }

    .hero-controls {
      align-self: stretch;
    }

    .kpi-group {
      flex-direction: column;
    }

    .kpi-chip {
      inline-size: 100%;
      justify-content: space-between;
    }

    .hero-cta-row {
      flex-direction: column;
      align-items: stretch;
    }

    .hero-cta {
      inline-size: 100%;
    }

    .mini-toc ul {
      gap: 0.5rem;
    }

    .mini-toc a {
      font-size: 0.875rem;
      padding: 0.625rem 1rem;
    }

    .method-bullets li {
      grid-template-columns: 1fr;
      padding: 1.75rem;
    }

    .chart-frame {
      min-block-size: 16rem;
      padding: 1.5rem;
    }

    .chart-frame.multiples {
      grid-template-columns: 1fr;
    }

    .chart-frame.multiples canvas {
      min-block-size: 12rem;
    }

    .insight-card {
      padding: 1.75rem;
    }

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

    .signature-text {
      font-size: 1rem;
    }

    .signature-brand {
      font-size: 1.25rem;
    }
  }

  @media (width <= 40rem) {
    .mini-toc ul {
      flex-wrap: nowrap;
      overflow-x: auto;
      padding-block-end: 1rem;
      margin: 0 -0.625rem;
      padding-inline: 0.625rem;
      scroll-snap-type: x mandatory;
    }

    .mini-toc li {
      scroll-snap-align: start;
    }

    .mini-toc ul::-webkit-scrollbar {
      height: 0.5rem;
    }

    .mini-toc ul::-webkit-scrollbar-track {
      background: var(--bg);
      border-radius: var(--radius-full);
    }

    .mini-toc ul::-webkit-scrollbar-thumb {
      background: var(--accent-gradient);
      border-radius: var(--radius-full);
    }
  }

  @media (hover: none) {
    .hero-cta:hover,
    .insight-card:hover,
    .method-bullets li:hover {
      transform: none;
    }
  }

  @supports (height: 100dvh) {
    body {
      min-block-size: 100dvh;
    }
  }
}

@media (prefers-contrast: more) {
  :root {
    --border: oklch(55% 0.02 250 / 0.7);
    --border-subtle: oklch(55% 0.02 250 / 0.5);
  }
}

@media print {
  body::before,
  body::after,
  .hero-overlay,
  .hero-controls,
  .mini-toc,
  #progress-bar,
  .skip-link {
    display: none;
  }

  .hero {
    padding-block: 2rem;
    min-block-size: auto;
  }

  .study-section {
    page-break-inside: avoid;
    break-inside: avoid;
  }
}

/* Personal Insight Cards */
.personal-insight-card {
  position: absolute;
  max-width: 320px;
  padding: 1.25rem 1.5rem;
  background: var(--bg-overlay);
  backdrop-filter: blur(24px) saturate(180%);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl), 0 0 40px oklch(80% 0.18 195 / 0.2);
  z-index: 10;
  opacity: 0;
  transform: translateY(15px) scale(0.96);
  transition: opacity 0.7s cubic-bezier(0.34, 1.56, 0.64, 1),
              transform 0.7s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.personal-insight-card.is-visible {
  opacity: 1;
  transform: translateY(0) scale(1);
}

.insight-icon {
  display: inline-block;
  font-size: 1.75rem;
  margin-bottom: 0.625rem;
  animation: iconBounce 2s ease-in-out infinite;
}

@keyframes iconBounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}

.insight-text {
  font-size: 0.9375rem;
  line-height: 1.6;
  color: var(--fg-muted);
  margin: 0;
}

.insight-top-right {
  top: 1.25rem;
  right: 1.25rem;
}

.insight-top-left {
  top: 1.25rem;
  left: 1.25rem;
}

.insight-bottom-right {
  bottom: 1.25rem;
  right: 1.25rem;
}

.insight-bottom-left {
  bottom: 1.25rem;
  left: 1.25rem;
}

@media (width <= 48rem) {
  .personal-insight-card {
    max-width: calc(100% - 2.5rem);
    position: relative;
    top: auto !important;
    right: auto !important;
    bottom: auto !important;
    left: auto !important;
    margin-top: 1.25rem;
  }
}

/* Chart Animations */
@keyframes chartCardEntrance {
  0% {
    opacity: 0;
    transform: translateY(30px) scale(0.97);
  }
  100% {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

canvas[id^="chart-"] {
  transition: opacity 0.6s ease;
}

canvas[id^="chart-"]:not([data-animated]) {
  opacity: 0;
}

canvas[id^="chart-"][data-animated] {
  opacity: 1;
}

/* Shareable Insights */
.share-insight-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.625rem 1.125rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--fg-muted);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  opacity: 0;
  position: relative;
  overflow: hidden;
}

.share-insight-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--accent-gradient);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.insight-card:hover .share-insight-btn {
  opacity: 1;
}

.share-insight-btn:hover {
  color: white;
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md), 0 0 20px oklch(80% 0.18 195 / 0.3);
}

.share-insight-btn:hover::before {
  opacity: 1;
}

.share-insight-btn:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.share-insight-btn svg {
  flex-shrink: 0;
  position: relative;
  z-index: 1;
}

.share-insight-btn span {
  position: relative;
  z-index: 1;
}

.share-notification {
  animation: shareNotificationSlide 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes shareNotificationSlide {
  0% {
    opacity: 0;
    transform: translateY(30px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (width <= 48rem) {
  .share-insight-btn {
    opacity: 1;
    font-size: 0.8125rem;
    padding: 0.5rem 0.875rem;
  }
}

@layer components {
  .visually-hidden {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0, 0, 0, 0) !important;
    white-space: nowrap !important;
    border: 0 !important;
  }

  body[data-page='study'] {
    background: var(--bg);
    color: var(--fg);
  }

  body[data-page='study'] .elevator-pitch {
    margin: calc(var(--safe-top) + 1.5rem) auto 0;
    inline-size: min(1080px, 94vw);
    padding: 1rem 1.5rem;
    border-radius: var(--radius-full);
    background: var(--bg-overlay);
    backdrop-filter: blur(16px) saturate(160%);
    border: 1px solid var(--border);
    font-size: 1rem;
    color: var(--fg-muted);
    text-align: center;
    box-shadow: var(--shadow-md);
  }

  body[data-page='study'] .hero--study {
    min-block-size: clamp(480px, 70vh, 680px);
    text-align: center;
    gap: 1.5rem;
  }

  body[data-page='study'] .hero--study .theme-toggle {
    position: absolute;
    inset-block-start: calc(1.75rem + var(--safe-top));
    inset-inline-end: calc(1.75rem + var(--safe-right));
  }

  body[data-page='study'] .hero--study h1 {
    margin-inline: auto;
    font-family: 'Source Serif Pro', var(--font-serif);
  }

  body[data-page='study'] .tagline {
    font-size: 1.0625rem;
    color: var(--fg-muted);
    max-inline-size: 75ch;
    margin-inline: auto;
    line-height: 1.7;
  }

  body[data-page='study'] .hero-actions {
    display: flex;
    justify-content: center;
    gap: 1.25rem;
    flex-wrap: wrap;
    margin-top: 1.25rem;
  }

  .btn-primary,
  .btn-secondary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.625rem;
    padding: 1rem 2rem;
    border-radius: var(--radius-full);
    font-weight: 700;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    min-inline-size: 11rem;
    position: relative;
    overflow: hidden;
  }

  .btn-primary::before,
  .btn-secondary::before {
    content: '';
    position: absolute;
    inset: 0;
    transition: opacity 0.35s ease;
  }

  .btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: var(--shadow-lg), 0 0 30px oklch(80% 0.18 195 / 0.3);
  }

  .btn-primary::before {
    background: white;
    opacity: 0;
  }

  .btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl), 0 0 50px oklch(80% 0.18 195 / 0.5);
  }

  .btn-primary:hover::before {
    opacity: 0.15;
  }

  .btn-secondary {
    border: 1.5px solid var(--border);
    background: var(--bg-overlay);
    color: var(--fg);
  }

  .btn-secondary::before {
    background: var(--accent-gradient-soft);
    opacity: 0;
  }

  .btn-secondary:hover,
  .btn-secondary:focus-visible {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-md), 0 0 25px oklch(80% 0.18 195 / 0.2);
    transform: translateY(-3px);
  }

  .btn-secondary:hover::before {
    opacity: 1;
  }

  body[data-page='study'] .anchor-layout {
    display: grid;
    grid-template-columns: minmax(0, 280px) minmax(0, 1fr);
    gap: clamp(1.75rem, 5vw, 3.5rem);
    inline-size: min(1280px, 94vw);
    margin: var(--section-gap) auto;
  }

  body[data-page='study'] .anchor-nav {
    position: sticky;
    top: calc(7rem + var(--safe-top));
    align-self: start;
    display: grid;
    gap: 0.5rem;
    padding: 1.5rem;
    border-radius: var(--radius-xl);
    border: 1px solid var(--border);
    background: var(--bg-overlay);
    backdrop-filter: blur(16px) saturate(160%);
    box-shadow: var(--shadow-lg);
  }

  body[data-page='study'] .anchor-nav a {
    display: block;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    color: var(--fg-muted);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
  }

  body[data-page='study'] .anchor-nav a::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  body[data-page='study'] .anchor-nav a span {
    position: relative;
    z-index: 1;
  }

  body[data-page='study'] .anchor-nav a:is(:hover, :focus-visible),
  body[data-page='study'] .anchor-nav a.active {
    color: var(--fg);
    transform: translateX(4px);
  }

  body[data-page='study'] .anchor-nav a:is(:hover, :focus-visible)::before,
  body[data-page='study'] .anchor-nav a.active::before {
    opacity: 1;
  }

  body[data-page='study'] .anchor-content {
    display: grid;
    gap: clamp(2.5rem, 5vw, 3.5rem);
  }

  body[data-page='study'] h2,
  body[data-page='study'] h3 {
    font-family: 'Source Serif Pro', var(--font-serif);
  }

  body[data-page='study'] .text-block {
    color: var(--fg-muted);
    line-height: 1.75;
  }

  body[data-page='study'] .tech-bubble {
    border: 1px solid var(--border);
    border-radius: var(--radius-2xl);
    padding: clamp(1.75rem, 3.5vw, 2.75rem);
    background: var(--bg-elevated);
    display: grid;
    gap: 1.75rem;
    box-shadow: var(--shadow-lg);
  }

  body[data-page='study'] .tech-grid {
    display: grid;
    gap: 1.25rem;
  }

  @media (width > 56rem) {
    body[data-page='study'] .tech-grid {
      grid-template-columns: repeat(3, minmax(0, 1fr));
    }
  }

  body[data-page='study'] .tech-card {
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    background: var(--bg);
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
  }

  body[data-page='study'] .tech-card:hover {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-md), 0 0 25px oklch(80% 0.18 195 / 0.15);
    transform: translateY(-3px);
  }

  body[data-page='study'] .key-takeaway {
    border-left: 4px solid var(--accent-cyan);
    padding: 1rem 1.25rem;
    background: var(--accent-gradient-soft);
    border-radius: var(--radius-md);
    color: var(--fg);
    font-weight: 600;
    box-shadow: inset 0 1px 2px oklch(0% 0 0 / 0.05);
  }

  body[data-page='study'] .prose.prose-invert p,
  body[data-page='study'] .prose.prose-invert li {
    color: var(--fg-muted);
  }

  body[data-page='study'] .chart-card {
    border: 1px solid var(--border);
    border-radius: var(--radius-2xl);
    padding: clamp(1.75rem, 3.5vw, 3rem);
    background: var(--bg-elevated);
    display: grid;
    gap: 1.25rem;
    box-shadow: var(--shadow-lg);
  }

  body[data-page='study'] .chart-card canvas {
    inline-size: 100%;
  }

  body[data-page='study'] .chart-summary {
    color: var(--fg-muted);
    line-height: 1.75;
  }

  body[data-page='study'] .table-like {
    width: 100%;
    border-collapse: collapse;
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-md);
  }

  body[data-page='study'] .table-like th,
  body[data-page='study'] .table-like td {
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--border-subtle);
    text-align: left;
    font-size: 0.9375rem;
  }

  body[data-page='study'] .table-like thead {
    background: oklch(from var(--bg-elevated) calc(l - 0.015) c h);
  }

  body[data-page='study'] .table-like tbody tr {
    transition: background 0.3s ease;
  }

  body[data-page='study'] .table-like tbody tr:hover {
    background: var(--accent-gradient-soft);
  }

  body[data-page='study'] .table-like tbody tr:last-child td {
    border-bottom: none;
  }

  body[data-page='study'] .derived-insights {
    border-radius: var(--radius-xl);
    border: 2px dashed var(--border);
    background: oklch(16% 0.02 250 / 0.4);
    padding: 1.5rem 1.75rem;
    display: grid;
    gap: 1rem;
    box-shadow: var(--shadow-md);
  }

  [data-theme='light'] body[data-page='study'] .derived-insights {
    background: oklch(96% 0.01 240 / 0.75);
  }

  body[data-page='study'] .download-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 1.25rem;
  }

  body[data-page='study'] .download-buttons .btn-secondary,
  body[data-page='study'] .download-buttons .print-button {
    min-inline-size: auto;
    padding-inline: 1.5rem;
  }

  body[data-page='study'] .print-button {
    border-radius: var(--radius-full);
    border: 1.5px solid var(--border);
    background: transparent;
    color: var(--fg);
    font-weight: 700;
    padding: 1rem 1.75rem;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
  }

  body[data-page='study'] .print-button::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient-soft);
    opacity: 0;
    transition: opacity 0.35s ease;
  }

  body[data-page='study'] .print-button:hover,
  body[data-page='study'] .print-button:focus-visible {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-md), 0 0 25px oklch(80% 0.18 195 / 0.2);
    transform: translateY(-3px);
  }

  body[data-page='study'] .print-button:hover::before {
    opacity: 1;
  }

  body[data-page='study'] footer {
    margin-top: clamp(3.5rem, 7vw, 5rem);
    padding: 3rem var(--container-padding) calc(3rem + var(--safe-bottom));
    border-top: 1px solid var(--border);
    text-align: center;
    color: var(--fg-muted);
    font-size: 0.9375rem;
  }

  @media (width <= 64rem) {
    body[data-page='study'] .anchor-layout {
      grid-template-columns: 1fr;
    }

    body[data-page='study'] .anchor-nav {
      position: relative;
      top: 0;
      order: -1;
      display: flex;
      flex-direction: row;
      align-items: center;
      gap: 0.625rem;
      overflow-x: auto;
      white-space: nowrap;
    }
  }

  @media (width <= 48rem) {
    body[data-page='study'] .hero--study .theme-toggle {
      position: static;
      margin-inline: auto;
    }

    body[data-page='study'] .anchor-nav {
      padding: 1.25rem;
    }
  }
}

@layer utilities {
  .list-disc {
    list-style: disc;
  }

  .pl-6 {
    padding-inline-start: 1.75rem;
  }

  .space-y-3 > * + * {
    margin-block-start: 0.875rem;
  }

  .text-sm {
    font-size: 0.9375rem;
    line-height: 1.6;
  }

  .text-xs {
    font-size: 0.8125rem;
    line-height: 1.5;
  }

  .text-slate-400 {
    color: var(--fg-subtle);
  }

  .mt-4 {
    margin-block-start: 1.25rem;
  }

  .max-w-none {
    max-inline-size: none;
  }

  .prose {
    display: grid;
    gap: 1.5rem;
    line-height: 1.8;
    color: var(--fg);
  }

  .prose h3 {
    font-family: var(--font-serif);
    font-size: 1.375rem;
  }

  .prose ul {
    padding-inline-start: 1.75rem;
    display: grid;
    gap: 0.875rem;
  }

  .prose li::marker {
    color: var(--accent-cyan);
  }

  .prose-invert {
    color: var(--fg);
  }

  body[data-theme='light'] .prose-invert {
    color: var(--fg);
  }
}