/*
 * ============================================================
 * QUANTUM NEXUM — Design System CSS
 * ============================================================
 * Light-first, dark-capable.
 * Sun/Moon toggle in top-right corner.
 *
 * DESIGN PHILOSOPHY:
 * - NOT another blue-primary SaaS site
 * - NOT Inter/Roboto/system-font generic
 * - Inspired by Stripe's rigor, Apple's restraint,
 *   IBM Carbon's token system — but none of their aesthetics
 * - Cryptographic precision meets quantum energy
 * ============================================================
 */

/* ============================================================
   0. FONT IMPORTS
   Using distinctive, non-generic typefaces.
   - Display: "Outfit" — geometric, modern, engineered feel
   - Body: "Source Serif 4" — scholarly authority, readable
   - Mono: "JetBrains Mono" — best-in-class for code/crypto
   ============================================================ */
/* Self-hosted variable fonts (no external dependencies) */
@font-face {
  font-family: 'Outfit';
  font-style: normal;
  font-weight: 300 800;
  font-display: swap;
  src: url('/static/fonts/outfit-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

@font-face {
  font-family: 'Source Serif 4';
  font-style: normal;
  font-weight: 300 700;
  font-display: swap;
  src: url('/static/fonts/source-serif-4-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

@font-face {
  font-family: 'Source Serif 4';
  font-style: italic;
  font-weight: 400 500;
  font-display: swap;
  src: url('/static/fonts/source-serif-4-italic-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

@font-face {
  font-family: 'JetBrains Mono';
  font-style: normal;
  font-weight: 400 600;
  font-display: swap;
  src: url('/static/fonts/jetbrains-mono-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* ============================================================
   1. DESIGN TOKENS — CSS Custom Properties
   ============================================================
   Semantic naming convention (not raw color names):
   --qn-surface-*   → background layers
   --qn-text-*      → typography colors
   --qn-accent-*    → brand / interactive
   --qn-border-*    → separators
   --qn-shadow-*    → elevation
   --qn-status-*    → success/warn/error/info
   --qn-space-*     → spacing scale
   --qn-radius-*    → corner radii
   --qn-motion-*    → animation durations
   ============================================================ */

:root {
  /* ---- Color Mode Flag ---- */
  color-scheme: light dark;

  /* ---- LIGHT THEME (Default) ---- */

  /* Surfaces: warm-tinted, NOT pure white
     Avoids the sterile #FFF that every SaaS uses */
  --qn-surface-ground:    #F8F6F3;  /* warm parchment base */
  --qn-surface-primary:   #FFFFFF;  /* cards, elevated content */
  --qn-surface-secondary: #F0EDE8;  /* recessed areas, sidebars */
  --qn-surface-tertiary:  #E6E2DB;  /* deeper recesses */
  --qn-surface-inverse:   #1B1A17;  /* inverted sections */
  --qn-surface-overlay:   rgba(27, 26, 23, 0.6); /* modals backdrop */

  /* Text: NOT pure black — warm dark for readability
     Stripe uses #0A2540 (blue-black), we use warm-black */
  --qn-text-primary:      #1B1A17;  /* headings, strong content */
  --qn-text-secondary:    #4A4740;  /* body text */
  --qn-text-tertiary:     #7A766D;  /* captions, metadata */
  --qn-text-disabled:     #B5B0A6;  /* inactive elements */
  --qn-text-inverse:      #F8F6F3;  /* text on dark surfaces */
  --qn-text-link:         var(--qn-accent-primary);

  /* Accent: Teal-Cyan — NOT blue, NOT purple
     Quantum computing references: superposition states,
     cold/cryogenic environments, electron orbital colors.
     This is our differentiator. */
  --qn-accent-primary:    #0D9488;  /* teal — trust + innovation */
  --qn-accent-hover:      #0F766E;  /* deeper on hover */
  --qn-accent-pressed:    #115E59;  /* deepest on active */
  --qn-accent-subtle:     #CCFBF1;  /* teal tint for highlights */
  --qn-accent-muted:      #99F6E4;  /* secondary highlight */

  /* Secondary accent: warm amber — complements teal
     NOT a random second color — this is the "energy"
     to teal's "precision" */
  --qn-accent-secondary:  #D97706;  /* amber */
  --qn-accent-secondary-subtle: #FEF3C7;

  /* Borders: subtle, warm-toned */
  --qn-border-default:    #E0DBD3;
  --qn-border-subtle:     #EBE7E1;
  --qn-border-strong:     #C5BFB5;
  --qn-border-focus:      var(--qn-accent-primary);

  /* Shadows: warm-tinted, layered for realism
     NOT the generic rgba(0,0,0,0.1) everyone uses */
  --qn-shadow-xs:   0 1px 2px rgba(27, 26, 23, 0.04);
  --qn-shadow-sm:   0 1px 3px rgba(27, 26, 23, 0.06),
                    0 1px 2px rgba(27, 26, 23, 0.04);
  --qn-shadow-md:   0 4px 6px rgba(27, 26, 23, 0.05),
                    0 2px 4px rgba(27, 26, 23, 0.03);
  --qn-shadow-lg:   0 10px 25px rgba(27, 26, 23, 0.07),
                    0 4px 10px rgba(27, 26, 23, 0.04);
  --qn-shadow-xl:   0 20px 50px rgba(27, 26, 23, 0.10),
                    0 8px 20px rgba(27, 26, 23, 0.05);
  --qn-shadow-glow: 0 0 20px rgba(13, 148, 136, 0.15);

  /* Status colors — accessible contrast ratios verified */
  --qn-status-success:      #059669;
  --qn-status-success-bg:   #ECFDF5;
  --qn-status-warning:      #D97706;
  --qn-status-warning-bg:   #FFFBEB;
  --qn-status-error:        #DC2626;
  --qn-status-error-bg:     #FEF2F2;
  --qn-status-info:         #0D9488;
  --qn-status-info-bg:      #F0FDFA;

  /* ---- SPACING SCALE (not 8px grid — 6px base for uniqueness) ---- */
  --qn-space-1:   0.375rem;   /*  6px */
  --qn-space-2:   0.75rem;    /* 12px */
  --qn-space-3:   1.125rem;   /* 18px */
  --qn-space-4:   1.5rem;     /* 24px */
  --qn-space-5:   2.25rem;    /* 36px */
  --qn-space-6:   3rem;       /* 48px */
  --qn-space-7:   4.5rem;     /* 72px */
  --qn-space-8:   6rem;       /* 96px */
  --qn-space-9:   9rem;       /* 144px */

  /* ---- BORDER RADIUS (restrained — not everything is a pill) ---- */
  --qn-radius-xs:   2px;
  --qn-radius-sm:   4px;
  --qn-radius-md:   6px;
  --qn-radius-lg:   10px;
  --qn-radius-xl:   16px;
  --qn-radius-full: 9999px;

  /* ---- TYPOGRAPHY SCALE ---- */
  --qn-font-display:  'Outfit', sans-serif;
  --qn-font-body:     'Source Serif 4', Georgia, serif;
  --qn-font-mono:     'JetBrains Mono', 'Fira Code', monospace;

  --qn-text-xs:    0.75rem;    /* 12px */
  --qn-text-sm:    0.875rem;   /* 14px */
  --qn-text-base:  1rem;       /* 16px */
  --qn-text-lg:    1.125rem;   /* 18px */
  --qn-text-xl:    1.25rem;    /* 20px */
  --qn-text-2xl:   1.5rem;     /* 24px */
  --qn-text-3xl:   1.875rem;   /* 30px */
  --qn-text-4xl:   2.25rem;    /* 36px */
  --qn-text-5xl:   3rem;       /* 48px */
  --qn-text-6xl:   3.75rem;    /* 60px */
  --qn-text-hero:  clamp(2.5rem, 5vw + 1rem, 5rem);

  --qn-leading-tight:   1.2;
  --qn-leading-normal:  1.6;
  --qn-leading-relaxed: 1.8;

  --qn-tracking-tight:  -0.025em;
  --qn-tracking-normal: 0;
  --qn-tracking-wide:   0.05em;
  --qn-tracking-wider:  0.1em;

  /* ---- MOTION TOKENS ---- */
  /* IBM Carbon-inspired: productive vs expressive */
  --qn-motion-instant:    80ms;
  --qn-motion-productive: 150ms;   /* UI feedback */
  --qn-motion-expressive: 300ms;   /* page transitions */
  --qn-motion-dramatic:   500ms;   /* hero animations */
  --qn-motion-ease-out:   cubic-bezier(0.16, 1, 0.3, 1);
  --qn-motion-ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --qn-motion-spring:     cubic-bezier(0.34, 1.56, 0.64, 1);

  /* ---- Z-INDEX SCALE ---- */
  --qn-z-base:      0;
  --qn-z-raised:    10;
  --qn-z-dropdown:  100;
  --qn-z-sticky:    200;
  --qn-z-overlay:   300;
  --qn-z-modal:     400;
  --qn-z-toast:     500;
  --qn-z-tooltip:   600;
  --qn-z-max:       9999;

  /* ---- CONTAINER WIDTHS ---- */
  --qn-container-sm:   640px;
  --qn-container-md:   768px;
  --qn-container-lg:   1024px;
  --qn-container-xl:   1200px;
  --qn-container-2xl:  1400px;

  /* ---- LEGACY VARIABLE ALIASES ----
     Maps old prod.css variables to new semantic tokens.
     Enables section CSS files (vault.css, forge.css, etc.)
     to work without modification during migration.
     Remove once all CSS is updated to --qn-* tokens. */
  --bg:         var(--qn-surface-ground);
  --bg-alt:     var(--qn-surface-secondary);
  --panel:      var(--qn-surface-primary);
  --fg:         var(--qn-text-primary);
  --muted:      var(--qn-text-tertiary);
  --accent:     var(--qn-accent-primary);
  --accent2:    var(--qn-accent-secondary);
  --line:       var(--qn-border-default);
  --line-light: var(--qn-border-subtle);
}


/* ============================================================
   2. DARK THEME
   ============================================================
   Activated via [data-theme="dark"] on <html>.
   NOT just inverted — carefully rebalanced surfaces,
   reduced contrast, warmer dark tones.
   ============================================================ */

[data-theme="dark"] {
  /* Surfaces: warm charcoal, NOT pure black
     Pure black (#000) causes halation on OLED.
     These have subtle warm undertone. */
  --qn-surface-ground:    #141312;
  --qn-surface-primary:   #1E1D1B;
  --qn-surface-secondary: #272522;
  --qn-surface-tertiary:  #302E2A;
  --qn-surface-inverse:   #F8F6F3;
  --qn-surface-overlay:   rgba(0, 0, 0, 0.7);

  /* Text: NOT pure white — softer for dark bg */
  --qn-text-primary:      #EDEBE7;
  --qn-text-secondary:    #B5B0A6;
  --qn-text-tertiary:     #7A766D;
  --qn-text-disabled:     #4A4740;
  --qn-text-inverse:      #1B1A17;

  /* Accents: slightly brighter for dark bg contrast */
  --qn-accent-primary:    #14B8A6;
  --qn-accent-hover:      #2DD4BF;
  --qn-accent-pressed:    #0D9488;
  --qn-accent-subtle:     rgba(20, 184, 166, 0.12);
  --qn-accent-muted:      rgba(20, 184, 166, 0.08);

  --qn-accent-secondary:  #F59E0B;
  --qn-accent-secondary-subtle: rgba(245, 158, 11, 0.12);

  /* Borders: lighter for visibility on dark */
  --qn-border-default:    #302E2A;
  --qn-border-subtle:     #272522;
  --qn-border-strong:     #4A4740;

  /* Shadows: more aggressive on dark backgrounds */
  --qn-shadow-xs:   0 1px 2px rgba(0, 0, 0, 0.2);
  --qn-shadow-sm:   0 1px 3px rgba(0, 0, 0, 0.3),
                    0 1px 2px rgba(0, 0, 0, 0.2);
  --qn-shadow-md:   0 4px 6px rgba(0, 0, 0, 0.25),
                    0 2px 4px rgba(0, 0, 0, 0.15);
  --qn-shadow-lg:   0 10px 25px rgba(0, 0, 0, 0.35),
                    0 4px 10px rgba(0, 0, 0, 0.2);
  --qn-shadow-xl:   0 20px 50px rgba(0, 0, 0, 0.45),
                    0 8px 20px rgba(0, 0, 0, 0.25);
  --qn-shadow-glow: 0 0 30px rgba(20, 184, 166, 0.2);

  /* Status: adjusted for dark backgrounds */
  --qn-status-success:      #34D399;
  --qn-status-success-bg:   rgba(52, 211, 153, 0.1);
  --qn-status-warning:      #FBBF24;
  --qn-status-warning-bg:   rgba(251, 191, 36, 0.1);
  --qn-status-error:        #F87171;
  --qn-status-error-bg:     rgba(248, 113, 113, 0.1);
  --qn-status-info:         #2DD4BF;
  --qn-status-info-bg:      rgba(45, 212, 191, 0.1);

  /* Legacy aliases (dark) */
  --bg:         var(--qn-surface-ground);
  --bg-alt:     var(--qn-surface-secondary);
  --panel:      var(--qn-surface-primary);
  --fg:         var(--qn-text-primary);
  --muted:      var(--qn-text-tertiary);
  --accent:     var(--qn-accent-primary);
  --accent2:    var(--qn-accent-secondary);
  --line:       var(--qn-border-default);
  --line-light: var(--qn-border-subtle);
}

/* Also respect OS-level preference as fallback */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --qn-surface-ground:    #141312;
    --qn-surface-primary:   #1E1D1B;
    --qn-surface-secondary: #272522;
    --qn-surface-tertiary:  #302E2A;
    --qn-surface-inverse:   #F8F6F3;
    --qn-surface-overlay:   rgba(0, 0, 0, 0.7);
    --qn-text-primary:      #EDEBE7;
    --qn-text-secondary:    #B5B0A6;
    --qn-text-tertiary:     #7A766D;
    --qn-text-disabled:     #4A4740;
    --qn-text-inverse:      #1B1A17;
    --qn-accent-primary:    #14B8A6;
    --qn-accent-hover:      #2DD4BF;
    --qn-accent-pressed:    #0D9488;
    --qn-accent-subtle:     rgba(20, 184, 166, 0.12);
    --qn-accent-muted:      rgba(20, 184, 166, 0.08);
    --qn-accent-secondary:  #F59E0B;
    --qn-accent-secondary-subtle: rgba(245, 158, 11, 0.12);
    --qn-border-default:    #302E2A;
    --qn-border-subtle:     #272522;
    --qn-border-strong:     #4A4740;
    --qn-shadow-xs:   0 1px 2px rgba(0, 0, 0, 0.2);
    --qn-shadow-sm:   0 1px 3px rgba(0, 0, 0, 0.3), 0 1px 2px rgba(0, 0, 0, 0.2);
    --qn-shadow-md:   0 4px 6px rgba(0, 0, 0, 0.25), 0 2px 4px rgba(0, 0, 0, 0.15);
    --qn-shadow-lg:   0 10px 25px rgba(0, 0, 0, 0.35), 0 4px 10px rgba(0, 0, 0, 0.2);
    --qn-shadow-xl:   0 20px 50px rgba(0, 0, 0, 0.45), 0 8px 20px rgba(0, 0, 0, 0.25);
    --qn-shadow-glow: 0 0 30px rgba(20, 184, 166, 0.2);
    --qn-status-success:    #34D399;
    --qn-status-success-bg: rgba(52, 211, 153, 0.1);
    --qn-status-warning:    #FBBF24;
    --qn-status-warning-bg: rgba(251, 191, 36, 0.1);
    --qn-status-error:      #F87171;
    --qn-status-error-bg:   rgba(248, 113, 113, 0.1);
    --qn-status-info:       #2DD4BF;
    --qn-status-info-bg:    rgba(45, 212, 191, 0.1);

    /* Legacy aliases (prefers-color-scheme dark) */
    --bg:         var(--qn-surface-ground);
    --bg-alt:     var(--qn-surface-secondary);
    --panel:      var(--qn-surface-primary);
    --fg:         var(--qn-text-primary);
    --muted:      var(--qn-text-tertiary);
    --accent:     var(--qn-accent-primary);
    --accent2:    var(--qn-accent-secondary);
    --line:       var(--qn-border-default);
    --line-light: var(--qn-border-subtle);
  }
}


/* ============================================================
   3. RESET & BASE
   ============================================================ */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 100%; /* respect user prefs, not 62.5% hack */
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  hanging-punctuation: first last;
}

body {
  font-family: var(--qn-font-body);
  font-size: var(--qn-text-base);
  font-weight: 400;
  line-height: var(--qn-leading-normal);
  color: var(--qn-text-secondary);
  background-color: var(--qn-surface-ground);
  transition: background-color var(--qn-motion-expressive) var(--qn-motion-ease-out),
              color var(--qn-motion-expressive) var(--qn-motion-ease-out);
  min-height: 100vh;
  overflow-x: hidden;
}

/* Accessibility: Respect reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Focus visible — keyboard-only focus ring */
:focus-visible {
  outline: 2px solid var(--qn-accent-primary);
  outline-offset: 3px;
  border-radius: var(--qn-radius-xs);
}

:focus:not(:focus-visible) {
  outline: none;
}

::selection {
  background-color: var(--qn-accent-subtle);
  color: var(--qn-text-primary);
}


/* ============================================================
   4. TYPOGRAPHY
   ============================================================ */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--qn-font-display);
  color: var(--qn-text-primary);
  line-height: var(--qn-leading-tight);
  letter-spacing: var(--qn-tracking-tight);
  font-weight: 600;
  text-wrap: balance;
}

h1 {
  font-size: var(--qn-text-hero);
  font-weight: 700;
  letter-spacing: -0.035em;
}

h2 {
  font-size: var(--qn-text-5xl);
  letter-spacing: -0.03em;
}

h3 {
  font-size: var(--qn-text-3xl);
  letter-spacing: -0.02em;
}

h4 {
  font-size: var(--qn-text-2xl);
}

h5 {
  font-size: var(--qn-text-xl);
  font-weight: 500;
}

h6 {
  font-size: var(--qn-text-lg);
  font-weight: 500;
}

p {
  max-width: 65ch; /* optimal line length for readability */
  text-wrap: pretty;
}

/* Eyebrow / Label — the small caps above headlines */
.qn-eyebrow {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-sm);
  font-weight: 500;
  letter-spacing: var(--qn-tracking-wider);
  text-transform: uppercase;
  color: var(--qn-accent-primary);
}

/* Monospace / code inline */
code, kbd, samp, .qn-mono {
  font-family: var(--qn-font-mono);
  font-size: 0.9em;
  background-color: var(--qn-surface-secondary);
  padding: 0.15em 0.4em;
  border-radius: var(--qn-radius-sm);
  border: 1px solid var(--qn-border-subtle);
}

/* Links — no underline by default, animated on hover */
a {
  color: var(--qn-text-link);
  text-decoration: none;
  transition: color var(--qn-motion-productive) var(--qn-motion-ease-out);
}

a:hover:not(.qn-btn) {
  color: var(--qn-accent-hover);
}

/* Underline animation for inline links */
.qn-link {
  position: relative;
  display: inline;
}

.qn-link::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 0;
  height: 1.5px;
  background-color: currentColor;
  transition: width var(--qn-motion-productive) var(--qn-motion-ease-out);
}

.qn-link:hover::after {
  width: 100%;
}

/* Lead paragraph */
.qn-lead {
  font-size: var(--qn-text-xl);
  line-height: var(--qn-leading-relaxed);
  color: var(--qn-text-secondary);
  max-width: 55ch;
}


/* ============================================================
   5. LAYOUT
   ============================================================ */

.qn-container {
  width: 100%;
  max-width: var(--qn-container-xl);
  margin-inline: auto;
  padding-inline: var(--qn-space-4);
}

.qn-container--narrow {
  max-width: var(--qn-container-md);
}

.qn-container--wide {
  max-width: var(--qn-container-2xl);
}

.qn-section {
  padding-block: var(--qn-space-8);
}

.qn-section--compact {
  padding-block: var(--qn-space-6);
}

.qn-section--hero {
  padding-block: var(--qn-space-9) var(--qn-space-8);
}

/* Grid system — NOT the same 12-col bootstrap everyone uses.
   Flexible, content-aware grids. */
.qn-grid {
  display: grid;
  gap: var(--qn-space-4);
}

.qn-grid--2 { grid-template-columns: repeat(2, 1fr); }
.qn-grid--3 { grid-template-columns: repeat(3, 1fr); }
.qn-grid--4 { grid-template-columns: repeat(4, 1fr); }

/* Auto-fit responsive grid — no media queries needed */
.qn-grid--auto {
  grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
}

/* Asymmetric layout — what the best sites use for visual interest */
.qn-grid--asymmetric {
  grid-template-columns: 1.4fr 1fr;
}

.qn-grid--sidebar {
  grid-template-columns: 280px 1fr;
}

@media (max-width: 768px) {
  .qn-grid--2,
  .qn-grid--3,
  .qn-grid--4,
  .qn-grid--asymmetric,
  .qn-grid--sidebar {
    grid-template-columns: 1fr;
  }
}


/* ============================================================
   6. NAVIGATION — Refined, not frosted-glass generic
   ============================================================ */

.qn-nav {
  position: sticky;
  top: 0;
  z-index: var(--qn-z-sticky);
  background-color: var(--qn-surface-ground);
  border-bottom: 1px solid var(--qn-border-subtle);
  transition: background-color var(--qn-motion-expressive) var(--qn-motion-ease-out),
              border-color var(--qn-motion-expressive) var(--qn-motion-ease-out);
}

/* Subtle bg change on scroll — class toggled via JS */
.qn-nav--scrolled {
  background-color: color-mix(in srgb, var(--qn-surface-ground) 85%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.qn-nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  max-width: var(--qn-container-xl);
  margin-inline: auto;
  padding-inline: var(--qn-space-4);
}

.qn-nav__brand {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-lg);
  font-weight: 700;
  color: var(--qn-text-primary);
  letter-spacing: var(--qn-tracking-tight);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: var(--qn-space-2);
}

.qn-nav__logo {
  flex-shrink: 0;
  transition: transform var(--qn-motion-productive) ease;
}
.qn-nav__brand:hover .qn-nav__logo {
  transform: scale(1.06);
}
.qn-nav__wordmark span {
  font-weight: 300;
}

.qn-nav__links {
  display: flex;
  align-items: center;
  gap: var(--qn-space-5);
  list-style: none;
}

.qn-nav__link {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-sm);
  font-weight: 500;
  color: var(--qn-text-secondary);
  text-decoration: none;
  transition: color var(--qn-motion-productive) var(--qn-motion-ease-out);
  letter-spacing: var(--qn-tracking-normal);
}

.qn-nav__link:hover,
.qn-nav__link--active {
  color: var(--qn-text-primary);
}

.qn-nav__actions {
  display: flex;
  align-items: center;
  gap: var(--qn-space-3);
}


/* ============================================================
   7. THEME TOGGLE — Sun/Moon in Top Right
   ============================================================ */

.qn-theme-toggle {
  position: relative;
  width: 44px;
  height: 44px;
  border: none;
  background: transparent;
  cursor: pointer;
  border-radius: var(--qn-radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--qn-motion-productive) var(--qn-motion-ease-out);
  color: var(--qn-text-secondary);
}

.qn-theme-toggle:hover {
  background-color: var(--qn-surface-secondary);
  color: var(--qn-text-primary);
}

.qn-theme-toggle__icon {
  width: 20px;
  height: 20px;
  transition: transform var(--qn-motion-expressive) var(--qn-motion-spring),
              opacity var(--qn-motion-productive) var(--qn-motion-ease-out);
}

/* Sun icon — visible in light mode */
.qn-theme-toggle__sun {
  position: absolute;
}

[data-theme="dark"] .qn-theme-toggle__sun {
  transform: rotate(90deg) scale(0);
  opacity: 0;
}

/* Moon icon — visible in dark mode */
.qn-theme-toggle__moon {
  position: absolute;
  transform: rotate(-90deg) scale(0);
  opacity: 0;
}

[data-theme="dark"] .qn-theme-toggle__moon {
  transform: rotate(0deg) scale(1);
  opacity: 1;
}


/* ============================================================
   8. BUTTONS
   ============================================================
   NOT pill-shaped by default. Slightly rounded, dense, purposeful.
   ============================================================ */

.qn-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--qn-space-2);
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-sm);
  font-weight: 500;
  line-height: 1;
  padding: 0.625rem 1.25rem;
  border: 1px solid transparent;
  border-radius: var(--qn-radius-md);
  cursor: pointer;
  transition: all var(--qn-motion-productive) var(--qn-motion-ease-out);
  text-decoration: none;
  white-space: nowrap;
  user-select: none;
}

.qn-btn:active {
  transform: scale(0.98);
}

/* Primary — filled teal */
.qn-btn--primary {
  background-color: var(--qn-accent-primary);
  color: #FFFFFF;
  border-color: var(--qn-accent-primary);
}

.qn-btn--primary:hover {
  background-color: var(--qn-accent-hover);
  color: #FFFFFF;
  border-color: var(--qn-accent-hover);
  box-shadow: var(--qn-shadow-md);
}

.qn-btn--primary:active {
  background-color: var(--qn-accent-pressed);
}

/* Secondary — outlined */
.qn-btn--secondary {
  background-color: transparent;
  color: var(--qn-text-primary);
  border-color: var(--qn-border-strong);
}

.qn-btn--secondary:hover {
  background-color: var(--qn-surface-secondary);
  border-color: var(--qn-text-tertiary);
}

/* Ghost — no border, just text */
.qn-btn--ghost {
  background-color: transparent;
  color: var(--qn-text-secondary);
  border-color: transparent;
  padding-inline: var(--qn-space-2);
}

.qn-btn--ghost:hover {
  color: var(--qn-text-primary);
  background-color: var(--qn-surface-secondary);
}

/* Danger */
.qn-btn--danger {
  background-color: var(--qn-status-error);
  color: #FFFFFF;
  border-color: var(--qn-status-error);
}

.qn-btn--danger:hover {
  background-color: #B91C1C;
  color: #FFFFFF;
  border-color: #B91C1C;
}

/* Sizes */
.qn-btn--sm {
  font-size: var(--qn-text-xs);
  padding: 0.4rem 0.875rem;
}

.qn-btn--lg {
  font-size: var(--qn-text-base);
  padding: 0.75rem 1.75rem;
}

/* Disabled */
.qn-btn:disabled,
.qn-btn[aria-disabled="true"] {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* Icon-only button */
.qn-btn--icon {
  width: 36px;
  height: 36px;
  padding: 0;
}


/* ============================================================
   9. CARDS
   ============================================================
   NOT shadow + rounded corners generic.
   Subtle border + elevation on interaction.
   ============================================================ */

.qn-card {
  background-color: var(--qn-surface-primary);
  border: 1px solid var(--qn-border-subtle);
  border-radius: var(--qn-radius-lg);
  padding: var(--qn-space-4);
  transition: border-color var(--qn-motion-productive) var(--qn-motion-ease-out),
              box-shadow var(--qn-motion-productive) var(--qn-motion-ease-out),
              transform var(--qn-motion-productive) var(--qn-motion-ease-out);
}

.qn-card:hover {
  border-color: var(--qn-border-default);
  box-shadow: var(--qn-shadow-md);
}

/* Interactive card — lifts on hover */
.qn-card--interactive {
  cursor: pointer;
}

.qn-card--interactive:hover {
  transform: translateY(-2px);
  box-shadow: var(--qn-shadow-lg);
}

/* Featured card — accent border top */
.qn-card--featured {
  border-top: 3px solid var(--qn-accent-primary);
  padding-top: calc(var(--qn-space-4) - 2px);
}

/* Compact card */
.qn-card--compact {
  padding: var(--qn-space-3);
}

/* Card header */
.qn-card__header {
  margin-bottom: var(--qn-space-3);
}

.qn-card__title {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-lg);
  font-weight: 600;
  color: var(--qn-text-primary);
}

.qn-card__subtitle {
  font-size: var(--qn-text-sm);
  color: var(--qn-text-tertiary);
  margin-top: var(--qn-space-1);
}


/* ============================================================
   10. FORMS & INPUTS
   ============================================================ */

.qn-input-group {
  display: flex;
  flex-direction: column;
  gap: var(--qn-space-1);
}

.qn-label {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-sm);
  font-weight: 500;
  color: var(--qn-text-primary);
}

.qn-input {
  font-family: var(--qn-font-body);
  font-size: var(--qn-text-base);
  padding: 0.5rem 0.75rem;
  background-color: var(--qn-surface-primary);
  color: var(--qn-text-primary);
  border: 1px solid var(--qn-border-default);
  border-radius: var(--qn-radius-md);
  transition: border-color var(--qn-motion-productive) var(--qn-motion-ease-out),
              box-shadow var(--qn-motion-productive) var(--qn-motion-ease-out);
  width: 100%;
}

.qn-input::placeholder {
  color: var(--qn-text-disabled);
}

.qn-input:hover {
  border-color: var(--qn-border-strong);
}

.qn-input:focus {
  outline: none;
  border-color: var(--qn-accent-primary);
  box-shadow: 0 0 0 3px var(--qn-accent-subtle);
}

.qn-input--error {
  border-color: var(--qn-status-error);
}

.qn-input--error:focus {
  box-shadow: 0 0 0 3px var(--qn-status-error-bg);
}

.qn-helper-text {
  font-size: var(--qn-text-xs);
  color: var(--qn-text-tertiary);
}

.qn-error-text {
  font-size: var(--qn-text-xs);
  color: var(--qn-status-error);
}

/* Textarea */
.qn-textarea {
  font-family: var(--qn-font-body);
  font-size: var(--qn-text-base);
  padding: 0.625rem 0.75rem;
  background-color: var(--qn-surface-primary);
  color: var(--qn-text-primary);
  border: 1px solid var(--qn-border-default);
  border-radius: var(--qn-radius-md);
  resize: vertical;
  min-height: 100px;
  width: 100%;
  transition: border-color var(--qn-motion-productive) var(--qn-motion-ease-out),
              box-shadow var(--qn-motion-productive) var(--qn-motion-ease-out);
}

.qn-textarea:focus {
  outline: none;
  border-color: var(--qn-accent-primary);
  box-shadow: 0 0 0 3px var(--qn-accent-subtle);
}

/* Select */
.qn-select {
  font-family: var(--qn-font-body);
  font-size: var(--qn-text-base);
  padding: 0.6rem 2.25rem 0.6rem 0.85rem;
  background-color: var(--qn-surface-secondary);
  color: var(--qn-text-primary);
  border: 1px solid var(--qn-border-strong);
  border-left: 3px solid var(--qn-accent-primary);
  border-radius: var(--qn-radius-md);
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='none' viewBox='0 0 12 12'%3E%3Cpath d='M3 4.5l3 3 3-3' stroke='%236AA6FF' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.85rem center;
  cursor: pointer;
  width: 100%;
  transition: all var(--qn-motion-productive) var(--qn-motion-ease-out);
}

.qn-select:hover {
  border-color: var(--qn-accent-primary);
  background-color: var(--qn-accent-subtle);
}

.qn-select:focus {
  outline: none;
  border-color: var(--qn-accent-primary);
  box-shadow: 0 0 0 3px var(--qn-accent-subtle);
}

.qn-select option {
  background: var(--qn-surface-primary);
  color: var(--qn-text-primary);
}


/* ============================================================
   11. CODE BLOCKS — PKI/Crypto output styling
   ============================================================ */

.qn-code-block {
  font-family: var(--qn-font-mono);
  font-size: var(--qn-text-sm);
  line-height: 1.7;
  background-color: var(--qn-surface-secondary);
  border: 1px solid var(--qn-border-subtle);
  border-radius: var(--qn-radius-lg);
  padding: var(--qn-space-4);
  overflow-x: auto;
  tab-size: 4;
}

[data-theme="dark"] .qn-code-block {
  background-color: #0D0C0B;
  border-color: var(--qn-border-default);
}

/* Code header with filename/language */
.qn-code-block__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--qn-space-2) var(--qn-space-4);
  background-color: var(--qn-surface-tertiary);
  border-bottom: 1px solid var(--qn-border-subtle);
  border-radius: var(--qn-radius-lg) var(--qn-radius-lg) 0 0;
  margin: calc(-1 * var(--qn-space-4));
  margin-bottom: var(--qn-space-3);
  padding-top: var(--qn-space-2);
}

.qn-code-block__filename {
  font-family: var(--qn-font-mono);
  font-size: var(--qn-text-xs);
  color: var(--qn-text-tertiary);
  font-weight: 500;
}

/* Syntax highlighting tokens (generic classes) */
.qn-token-keyword   { color: var(--qn-accent-primary); }
.qn-token-string    { color: var(--qn-accent-secondary); }
.qn-token-comment   { color: var(--qn-text-disabled); font-style: italic; }
.qn-token-function  { color: #7C3AED; }
.qn-token-number    { color: #059669; }
.qn-token-operator  { color: var(--qn-text-tertiary); }

[data-theme="dark"] .qn-token-keyword   { color: #2DD4BF; }
[data-theme="dark"] .qn-token-string    { color: #FBBF24; }
[data-theme="dark"] .qn-token-function  { color: #A78BFA; }
[data-theme="dark"] .qn-token-number    { color: #34D399; }


/* ============================================================
   12. BADGES & CHIPS
   ============================================================ */

.qn-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.25em;
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-xs);
  font-weight: 500;
  padding: 0.2em 0.6em;
  border-radius: var(--qn-radius-sm);
  line-height: 1.4;
}

.qn-badge--default {
  background-color: var(--qn-surface-secondary);
  color: var(--qn-text-secondary);
}

.qn-badge--accent {
  background-color: var(--qn-accent-subtle);
  color: var(--qn-accent-primary);
}

.qn-badge--success {
  background-color: var(--qn-status-success-bg);
  color: var(--qn-status-success);
}

.qn-badge--warning {
  background-color: var(--qn-status-warning-bg);
  color: var(--qn-status-warning);
}

.qn-badge--error {
  background-color: var(--qn-status-error-bg);
  color: var(--qn-status-error);
}

/* Dot indicator */
.qn-badge__dot {
  width: 6px;
  height: 6px;
  border-radius: var(--qn-radius-full);
  background-color: currentColor;
}


/* ============================================================
   13. TABLES — Certificate/Key data display
   ============================================================ */

.qn-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--qn-border-subtle);
  border-radius: var(--qn-radius-lg);
}

.qn-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--qn-text-sm);
}

.qn-table th {
  font-family: var(--qn-font-display);
  font-weight: 500;
  font-size: var(--qn-text-xs);
  letter-spacing: var(--qn-tracking-wide);
  text-transform: uppercase;
  text-align: left;
  padding: var(--qn-space-2) var(--qn-space-3);
  background-color: var(--qn-surface-secondary);
  color: var(--qn-text-tertiary);
  border-bottom: 1px solid var(--qn-border-default);
}

.qn-table td {
  padding: var(--qn-space-2) var(--qn-space-3);
  border-bottom: 1px solid var(--qn-border-subtle);
  color: var(--qn-text-secondary);
  vertical-align: top;
}

.qn-table tbody tr:last-child td {
  border-bottom: none;
}

.qn-table tbody tr:hover {
  background-color: var(--qn-surface-secondary);
}

/* Monospace cells for hashes, serial numbers, OIDs */
.qn-table td.qn-mono-cell {
  font-family: var(--qn-font-mono);
  font-size: var(--qn-text-xs);
  word-break: break-all;
}


/* ============================================================
   14. ALERTS & CALLOUTS
   ============================================================ */

.qn-alert {
  display: flex;
  gap: var(--qn-space-3);
  padding: var(--qn-space-3) var(--qn-space-4);
  border-radius: var(--qn-radius-md);
  border-left: 3px solid;
  font-size: var(--qn-text-sm);
}

.qn-alert--info {
  background-color: var(--qn-status-info-bg);
  border-color: var(--qn-status-info);
  color: var(--qn-text-secondary);
}

.qn-alert--success {
  background-color: var(--qn-status-success-bg);
  border-color: var(--qn-status-success);
}

.qn-alert--warning {
  background-color: var(--qn-status-warning-bg);
  border-color: var(--qn-status-warning);
}

.qn-alert--error {
  background-color: var(--qn-status-error-bg);
  border-color: var(--qn-status-error);
}

.qn-alert__title {
  font-family: var(--qn-font-display);
  font-weight: 600;
  font-size: var(--qn-text-sm);
  color: var(--qn-text-primary);
  margin-bottom: var(--qn-space-1);
}


/* ============================================================
   15. DIVIDERS & SEPARATORS
   ============================================================ */

.qn-divider {
  border: none;
  border-top: 1px solid var(--qn-border-subtle);
  margin-block: var(--qn-space-5);
}

.qn-divider--strong {
  border-color: var(--qn-border-default);
}


/* ============================================================
   16. LOADING STATES
   ============================================================ */

/* Skeleton loading */
.qn-skeleton {
  background: linear-gradient(
    90deg,
    var(--qn-surface-secondary) 25%,
    var(--qn-surface-tertiary) 50%,
    var(--qn-surface-secondary) 75%
  );
  background-size: 200% 100%;
  animation: qn-skeleton-pulse 1.5s ease-in-out infinite;
  border-radius: var(--qn-radius-sm);
}

@keyframes qn-skeleton-pulse {
  0%   { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Spinner */
.qn-spinner {
  width: 20px;
  height: 20px;
  border: 2px solid var(--qn-border-default);
  border-top-color: var(--qn-accent-primary);
  border-radius: var(--qn-radius-full);
  animation: qn-spin 0.6s linear infinite;
}

@keyframes qn-spin {
  to { transform: rotate(360deg); }
}


/* ============================================================
   17. TOOLTIP
   ============================================================ */

.qn-tooltip {
  position: relative;
}

.qn-tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%) translateY(4px);
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-xs);
  font-weight: 400;
  line-height: 1.4;
  white-space: nowrap;
  color: var(--qn-text-inverse);
  background-color: var(--qn-surface-inverse);
  padding: 0.3em 0.6em;
  border-radius: var(--qn-radius-sm);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--qn-motion-productive) var(--qn-motion-ease-out),
              transform var(--qn-motion-productive) var(--qn-motion-ease-out);
  z-index: var(--qn-z-tooltip);
}

.qn-tooltip:hover::after {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}


/* ============================================================
   18. HERO — Quantum-themed atmospheric background
   ============================================================ */

.qn-hero {
  position: relative;
  overflow: hidden;
  background-color: var(--qn-surface-ground);
}

/* Subtle grid pattern background — evokes circuitry */
.qn-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--qn-border-subtle) 1px, transparent 1px),
    linear-gradient(90deg, var(--qn-border-subtle) 1px, transparent 1px);
  background-size: 60px 60px;
  opacity: 0.5;
  mask-image: radial-gradient(ellipse at 30% 50%, black 20%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at 30% 50%, black 20%, transparent 70%);
}

/* Accent glow orb */
.qn-hero::after {
  content: '';
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    color-mix(in srgb, var(--qn-accent-primary) 8%, transparent) 0%,
    transparent 70%
  );
  top: -200px;
  right: -100px;
  pointer-events: none;
}

.qn-hero__content {
  position: relative;
  z-index: 1;
}


/* ============================================================
   19. CERTIFICATE HIERARCHY VISUALIZATION
   ============================================================
   Custom styling for the 22-CA tree view.
   ============================================================ */

.qn-tree {
  font-family: var(--qn-font-mono);
  font-size: var(--qn-text-sm);
  line-height: 2;
}

.qn-tree-item {
  position: relative;
  padding-left: var(--qn-space-4);
}

.qn-tree-item::before {
  content: '';
  position: absolute;
  left: 8px;
  top: 0;
  bottom: 0;
  width: 1px;
  background-color: var(--qn-border-default);
}

.qn-tree-item::after {
  content: '';
  position: absolute;
  left: 8px;
  top: 1em;
  width: 12px;
  height: 1px;
  background-color: var(--qn-border-default);
}

.qn-tree-item:last-child::before {
  bottom: calc(100% - 1em);
}

.qn-tree-label {
  display: inline-flex;
  align-items: center;
  gap: var(--qn-space-2);
  padding: 0.15em 0.5em;
  border-radius: var(--qn-radius-sm);
  cursor: default;
  transition: background-color var(--qn-motion-productive) var(--qn-motion-ease-out);
}

.qn-tree-label:hover {
  background-color: var(--qn-surface-secondary);
}

/* Root CA indicator */
.qn-tree-label--root {
  color: var(--qn-accent-primary);
  font-weight: 600;
}

/* Intermediate CA indicator */
.qn-tree-label--intermediate {
  color: var(--qn-accent-secondary);
  font-weight: 500;
}

/* Leaf / End-entity */
.qn-tree-label--leaf {
  color: var(--qn-text-secondary);
}


/* ============================================================
   20. ANIMATIONS — Entrance & Interaction
   ============================================================ */

/* Fade up on scroll (add via JS IntersectionObserver) */
.qn-animate-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--qn-motion-dramatic) var(--qn-motion-ease-out),
              transform var(--qn-motion-dramatic) var(--qn-motion-ease-out);
}

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

/* Staggered children */
.qn-stagger > * {
  opacity: 0;
  transform: translateY(16px);
  animation: qn-stagger-in var(--qn-motion-dramatic) var(--qn-motion-ease-out) forwards;
}

.qn-stagger > *:nth-child(1) { animation-delay: 0ms; }
.qn-stagger > *:nth-child(2) { animation-delay: 80ms; }
.qn-stagger > *:nth-child(3) { animation-delay: 160ms; }
.qn-stagger > *:nth-child(4) { animation-delay: 240ms; }
.qn-stagger > *:nth-child(5) { animation-delay: 320ms; }
.qn-stagger > *:nth-child(6) { animation-delay: 400ms; }

@keyframes qn-stagger-in {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Pulse — for live status indicators */
@keyframes qn-pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.5; }
}

.qn-pulse {
  animation: qn-pulse 2s ease-in-out infinite;
}

/* Quantum shimmer — for branding elements */
@keyframes qn-shimmer {
  0%   { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.qn-shimmer {
  background: linear-gradient(
    90deg,
    var(--qn-accent-primary) 0%,
    var(--qn-accent-muted) 50%,
    var(--qn-accent-primary) 100%
  );
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: qn-shimmer 3s linear infinite;
}


/* ============================================================
   21. UTILITY CLASSES
   ============================================================ */

/* Text alignment */
.qn-text-center  { text-align: center; }
.qn-text-right   { text-align: right; }

/* Flex utilities */
.qn-flex          { display: flex; }
.qn-flex-col      { flex-direction: column; }
.qn-items-center  { align-items: center; }
.qn-justify-between { justify-content: space-between; }
.qn-gap-1 { gap: var(--qn-space-1); }
.qn-gap-2 { gap: var(--qn-space-2); }
.qn-gap-3 { gap: var(--qn-space-3); }
.qn-gap-4 { gap: var(--qn-space-4); }
.qn-gap-5 { gap: var(--qn-space-5); }
.qn-gap-6 { gap: var(--qn-space-6); }

/* Spacing */
.qn-mt-1 { margin-top: var(--qn-space-1); }
.qn-mt-2 { margin-top: var(--qn-space-2); }
.qn-mt-3 { margin-top: var(--qn-space-3); }
.qn-mt-4 { margin-top: var(--qn-space-4); }
.qn-mt-5 { margin-top: var(--qn-space-5); }
.qn-mt-6 { margin-top: var(--qn-space-6); }
.qn-mb-1 { margin-bottom: var(--qn-space-1); }
.qn-mb-2 { margin-bottom: var(--qn-space-2); }
.qn-mb-3 { margin-bottom: var(--qn-space-3); }
.qn-mb-4 { margin-bottom: var(--qn-space-4); }
.qn-mb-5 { margin-bottom: var(--qn-space-5); }
.qn-mb-6 { margin-bottom: var(--qn-space-6); }

/* Visibility */
.qn-sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Truncate */
.qn-truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}


/* ============================================================
   22. FOOTER
   ============================================================ */

.qn-footer {
  background-color: var(--qn-surface-secondary);
  border-top: 1px solid var(--qn-border-subtle);
  padding-block: var(--qn-space-7);
  margin-top: var(--qn-space-8);
}

.qn-footer__grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: var(--qn-space-5);
}

@media (max-width: 768px) {
  .qn-footer__grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 480px) {
  .qn-footer__grid {
    grid-template-columns: 1fr;
  }
}

.qn-footer__heading {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-xs);
  font-weight: 600;
  letter-spacing: var(--qn-tracking-wider);
  text-transform: uppercase;
  color: var(--qn-text-tertiary);
  margin-bottom: var(--qn-space-3);
}

.qn-footer__links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--qn-space-2);
}

.qn-footer__link {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-sm);
  color: var(--qn-text-secondary);
  text-decoration: none;
  transition: color var(--qn-motion-productive) var(--qn-motion-ease-out);
}

.qn-footer__link:hover {
  color: var(--qn-text-primary);
}

.qn-footer__bottom {
  margin-top: var(--qn-space-6);
  padding-top: var(--qn-space-4);
  border-top: 1px solid var(--qn-border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: var(--qn-text-xs);
  color: var(--qn-text-tertiary);
}


/* ============================================================
   23. PRINT STYLES
   ============================================================ */

@media print {
  *,
  *::before,
  *::after {
    background: transparent !important;
    color: black !important;
    box-shadow: none !important;
  }

  body {
    font-size: 12pt;
    line-height: 1.5;
  }

  .qn-nav,
  .qn-theme-toggle,
  .qn-footer {
    display: none !important;
  }

  a[href]::after {
    content: " (" attr(href) ")";
    font-size: 0.8em;
    color: #666 !important;
  }
}


/* ============================================================
   LEGACY COMPATIBILITY LAYER
   ============================================================
   Components from prod.css that pages still reference.
   These bridge old class names to the new design system tokens.
   Remove as pages are rewritten to use new BEM classes.
   ============================================================ */

/* ---- Nav: Disabled Link ---- */
.qn-nav-disabled {
  padding: 8px 4px;
  color: var(--qn-text-disabled);
  font-size: var(--qn-text-sm);
  cursor: not-allowed;
  user-select: none;
}

/* ---- Nav: Dropdown (details/summary) ---- */
.qn-nav__dropdown {
  position: relative;
}
.qn-nav__dropdown summary {
  padding: 8px 4px;
  cursor: pointer;
  list-style: none;
  color: var(--qn-text-tertiary);
  font-size: var(--qn-text-sm);
  transition: color var(--qn-motion-productive) ease;
}
.qn-nav__dropdown summary::-webkit-details-marker { display: none; }
.qn-nav__dropdown summary:hover {
  color: var(--qn-text-primary);
}
.qn-nav__dropdown[open] summary {
  color: var(--qn-accent-primary);
}
.qn-nav__dropdown-content {
  position: absolute;
  top: 100%;
  left: 0;
  margin-top: 4px;
  background: var(--qn-surface-primary);
  border: 1px solid var(--qn-border-default);
  border-radius: var(--qn-radius-md);
  min-width: 200px;
  padding: 6px 0;
  z-index: var(--qn-z-dropdown);
  box-shadow: var(--qn-shadow-lg);
}
.qn-nav__dropdown-content a {
  display: block;
  padding: 8px 14px;
  color: var(--qn-text-secondary);
  font-size: var(--qn-text-sm);
  text-decoration: none;
  transition: all var(--qn-motion-productive) ease;
}
.qn-nav__dropdown-content a:hover {
  background: var(--qn-accent-subtle);
  color: var(--qn-accent-primary);
}
.qn-nav__dropdown-content hr {
  border: none;
  border-top: 1px solid var(--qn-border-subtle);
  margin: 4px 0;
}

/* ---- Legacy .qn-main wrapper ---- */
.qn-main {
  max-width: var(--qn-container-xl);
  margin: 0 auto;
  padding: var(--qn-space-5) var(--qn-space-4);
}

/* ---- Legacy hero styles ---- */
.qn-hero-simple {
  text-align: center;
  padding: var(--qn-space-8) 0 var(--qn-space-6);
}
.qn-hero-simple h1 {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-4xl);
  font-weight: 700;
  color: var(--qn-text-primary);
  margin-bottom: var(--qn-space-2);
}
.qn-hero-simple p {
  color: var(--qn-text-tertiary);
  max-width: 600px;
  margin: 0 auto var(--qn-space-2);
}

/* ---- Legacy section header ---- */
.qn-section-header {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: var(--qn-tracking-widest);
  color: var(--qn-accent-primary);
  margin: var(--qn-space-6) 0 var(--qn-space-3);
  padding-bottom: var(--qn-space-2);
  border-bottom: 1px solid var(--qn-border-subtle);
}

/* ---- Legacy subtitle ---- */
.qn-sub {
  color: var(--qn-text-tertiary);
  font-size: var(--qn-text-sm);
}

/* ---- Legacy keyword text ---- */
.qn-k {
  color: var(--qn-accent-primary);
  font-family: var(--qn-font-display);
  font-weight: 600;
  letter-spacing: var(--qn-tracking-wide);
  font-size: var(--qn-text-sm);
}

/* ---- Legacy actions wrapper ---- */
.qn-actions {
  display: flex;
  gap: var(--qn-space-3);
  justify-content: center;
  margin-top: var(--qn-space-4);
}

/* ---- Legacy grid ---- */
.qn-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--qn-space-4);
}

/* ---- Legacy card styling ---- */
.qn-card {
  background: var(--qn-surface-primary);
  border: 1px solid var(--qn-border-default);
  border-radius: var(--qn-radius-md);
  padding: var(--qn-space-5);
  transition: border-color var(--qn-motion-productive) ease,
              box-shadow var(--qn-motion-productive) ease;
}
.qn-card:hover {
  border-color: var(--qn-border-strong);
  box-shadow: var(--qn-shadow-sm);
}
.qn-card h2 {
  font-family: var(--qn-font-display);
  font-size: var(--qn-text-lg);
  font-weight: 600;
  color: var(--qn-text-primary);
  margin-bottom: var(--qn-space-2);
}

/* ---- Legacy buttons (flat modifier style) ---- */
.qn-btn.qn-primary {
  background: var(--qn-accent-primary);
  color: white;
  border-color: var(--qn-accent-primary);
}
.qn-btn.qn-primary:hover {
  background: var(--qn-accent-hover);
  border-color: var(--qn-accent-hover);
}
.qn-btn.qn-ghost {
  background: transparent;
  color: var(--qn-text-secondary);
  border-color: var(--qn-border-default);
}
.qn-btn.qn-ghost:hover {
  color: var(--qn-text-primary);
  border-color: var(--qn-border-strong);
}

/* ---- Legacy PKI card & dropdown ---- */
.qn-pki-links {
  display: flex;
  gap: var(--qn-space-2);
  margin-top: var(--qn-space-3);
  flex-wrap: wrap;
}
.qn-dropdown {
  position: relative;
}
.qn-dropdown summary {
  cursor: pointer;
  list-style: none;
}
.qn-dropdown summary::-webkit-details-marker { display: none; }
.qn-dropdown-content {
  position: absolute;
  top: 100%;
  left: 0;
  margin-top: 4px;
  background: var(--qn-surface-primary);
  border: 1px solid var(--qn-border-default);
  border-radius: var(--qn-radius-md);
  min-width: 240px;
  padding: 6px 0;
  z-index: var(--qn-z-dropdown);
  box-shadow: var(--qn-shadow-lg);
}
.qn-dropdown-content a {
  display: block;
  padding: 8px 14px;
  color: var(--qn-text-secondary);
  font-size: var(--qn-text-sm);
  text-decoration: none;
  transition: all var(--qn-motion-productive) ease;
}
.qn-dropdown-content a:hover {
  background: var(--qn-accent-subtle);
  color: var(--qn-accent-primary);
}
.qn-dropdown-content hr {
  border: none;
  border-top: 1px solid var(--qn-border-subtle);
  margin: 4px 0;
}

/* ---- Legacy disabled button ---- */
.qn-disabled,
.qn-btn:disabled,
.qn-btn[disabled] {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* ---- Legacy ribbon badge ---- */
.qn-ribbon {
  position: absolute;
  top: 12px;
  right: -8px;
  background: var(--qn-accent-primary);
  color: white;
  padding: 4px 12px;
  font-size: var(--qn-text-xs);
  font-weight: 600;
  border-radius: var(--qn-radius-sm) 0 0 var(--qn-radius-sm);
}

/* ---- Legacy overlay/sheet modal ---- */
.qn-overlay {
  position: fixed;
  inset: 0;
  background: var(--qn-surface-overlay);
  z-index: var(--qn-z-overlay);
  display: flex;
  align-items: center;
  justify-content: center;
}
.qn-sheet {
  background: var(--qn-surface-primary);
  border: 1px solid var(--qn-border-default);
  border-radius: var(--qn-radius-lg);
  padding: var(--qn-space-6);
  max-width: 480px;
  width: 90%;
  box-shadow: var(--qn-shadow-xl);
}

/* ── 101 floating button (bottom-right FAB) ── */
.simple-mode-btn {
  position: fixed;
  bottom: 20px;
  right: 20px;
  padding: 6px 12px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  font-size: 11px;
  color: var(--muted);
  text-decoration: none;
  z-index: 1000;
  transition: all 0.2s;
}
.simple-mode-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
  color: var(--fg);
}