/* ============================================================
   DESIGN TOKENS
   ============================================================ */
:root {
  /* Type scale */
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(0.9375rem, 0.85rem + 0.45vw, 1.0625rem);
  --text-lg:   clamp(1.125rem, 0.95rem + 0.85vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1rem    + 1.5vw,  2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);
  --text-3xl:  clamp(2.5rem,   1rem    + 4vw,    5rem);
  --text-hero: clamp(3rem,     0.5rem  + 7vw,    8rem);

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

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

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 800px;
  --content-wide: 1100px;

  /* Fonts */
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
}

/* Dark theme (primary) */
[data-theme="dark"], :root {
  --color-bg:              #0a0a0f;
  --color-surface:         #0f0f15;
  --color-surface-2:       #141420;
  --color-surface-offset:  #1a1a28;
  --color-surface-code:    #0d0d14;
  --color-divider:         #1e1e2e;
  --color-border:          rgba(255,255,255,0.07);
  --color-border-subtle:   rgba(255,255,255,0.04);

  --color-text:            #e8e8ed;
  --color-text-muted:      #8e8ea0;
  --color-text-faint:      #4a4a5a;

  --color-accent:          #d4a853;
  --color-accent-hover:    #e0b86a;
  --color-accent-glow:     rgba(212, 168, 83, 0.15);
  --color-accent-subtle:   rgba(212, 168, 83, 0.08);

  --color-success:         #4ade80;
  --color-error:           #f87171;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.4);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.5);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.6);
}

/* Light theme */
[data-theme="light"] {
  --color-bg:              #f8f8fb;
  --color-surface:         #ffffff;
  --color-surface-2:       #f3f3f8;
  --color-surface-offset:  #ebebf3;
  --color-surface-code:    #f0f0f6;
  --color-divider:         #e4e4ee;
  --color-border:          rgba(0,0,0,0.08);
  --color-border-subtle:   rgba(0,0,0,0.04);

  --color-text:            #18181f;
  --color-text-muted:      #6b6b7a;
  --color-text-faint:      #b0b0be;

  --color-accent:          #b5851e;
  --color-accent-hover:    #9a6e10;
  --color-accent-glow:     rgba(181, 133, 30, 0.12);
  --color-accent-subtle:   rgba(181, 133, 30, 0.06);

  --color-success:         #16a34a;
  --color-error:           #dc2626;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
}

/* ============================================================
   BASE RESET
   ============================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  -moz-text-size-adjust: none;
  -webkit-text-size-adjust: none;
  text-size-adjust: none;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: var(--space-20);
}

body {
  min-height: 100dvh;
  font-family: var(--font-body);
  font-size: var(--text-sm);
  line-height: 1.65;
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: background-color 0.3s var(--ease), color 0.3s var(--ease);
}

img, picture, video, canvas, svg { display: block; max-width: 100%; }
ul[role="list"], ol[role="list"] { list-style: none; }
input, button, textarea, select { font: inherit; color: inherit; }
h1, h2, h3, h4, h5, h6 { text-wrap: balance; line-height: 1.2; }
p, li { text-wrap: pretty; max-width: 68ch; }
button { cursor: pointer; background: none; border: none; }
table { border-collapse: collapse; width: 100%; }
a { color: inherit; text-decoration: none; }

::selection {
  background: var(--color-accent-glow);
  color: var(--color-text);
}

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

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

.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;
}

/* ============================================================
   LAYOUT
   ============================================================ */
.container {
  max-width: var(--content-default);
  margin-inline: auto;
  padding-inline: clamp(var(--space-4), 5vw, var(--space-8));
}

.container--wide {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: clamp(var(--space-4), 5vw, var(--space-8));
}

section {
  padding-block: clamp(var(--space-16), 10vw, var(--space-32));
}

/* ============================================================
   NAVIGATION
   ============================================================ */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  padding-block: var(--space-4);
  background: oklch(from var(--color-bg) l c h / 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border-subtle);
  transition: box-shadow 0.3s var(--ease);
}

.nav--scrolled {
  box-shadow: var(--shadow-sm);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-8);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--color-text);
  transition: opacity var(--transition);
}

.nav-logo:hover { opacity: 0.8; }

.nav-logo-mark {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  list-style: none;
}

.nav-links a {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  transition: color var(--transition);
  letter-spacing: 0.01em;
}

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

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

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 500;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  transition: all var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-accent);
  color: #0a0a0f;
  font-weight: 600;
}

.btn-primary:hover {
  background: var(--color-accent-hover);
  box-shadow: 0 0 20px var(--color-accent-glow);
}

.btn-ghost {
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
}

.btn-ghost:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.theme-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  transition: all var(--transition);
}

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

/* Mobile nav */
.nav-mobile-toggle {
  display: none;
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
}

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

/* ============================================================
   HERO
   ============================================================ */
.hero {
  padding-block: clamp(var(--space-20), 14vw, var(--space-32));
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 80% 60% at 50% -10%,
    rgba(212, 168, 83, 0.08) 0%,
    transparent 60%);
  pointer-events: none;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-16);
  align-items: center;
}

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

.hero-overline {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-accent);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: var(--space-6);
}

.hero-overline::before {
  content: '';
  width: 24px;
  height: 1px;
  background: var(--color-accent);
}

.hero-title {
  font-size: var(--text-3xl);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.0;
  margin-bottom: var(--space-3);
  color: var(--color-text);
}

.hero-greek {
  font-size: var(--text-lg);
  color: var(--color-accent);
  font-weight: 400;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-6);
  font-style: italic;
}

.hero-tagline {
  font-size: var(--text-lg);
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-4);
  line-height: 1.4;
  letter-spacing: -0.01em;
}

.hero-sub {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.7;
  margin-bottom: var(--space-8);
  max-width: 48ch;
}

.hero-actions {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.hero-actions .btn {
  font-size: var(--text-sm);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-lg);
}

.hero-illustration {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

@media (max-width: 768px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: var(--space-12);
  }
  .hero-illustration {
    order: -1;
    max-width: 320px;
    margin-inline: auto;
  }
}

/* ============================================================
   SECTION LABELS
   ============================================================ */
.section-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-accent);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: var(--space-4);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.section-label::before {
  content: '';
  width: 16px;
  height: 1px;
  background: var(--color-accent);
  flex-shrink: 0;
}

/* ============================================================
   PROBLEM SECTION
   ============================================================ */
.problem {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border-subtle);
  border-bottom: 1px solid var(--color-border-subtle);
}

.problem-heading {
  font-size: var(--text-xl);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: var(--space-6);
  color: var(--color-text);
}

.problem-body {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.75;
  margin-bottom: var(--space-12);
  max-width: 60ch;
}

.problem-body strong {
  color: var(--color-text);
  font-weight: 500;
}

.problem-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
}

.comparison-card {
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
}

.comparison-card--brain {
  border-color: rgba(212, 168, 83, 0.2);
  background: linear-gradient(135deg, var(--color-surface-2) 0%, var(--color-accent-subtle) 100%);
}

.comparison-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: var(--space-4);
}

.comparison-card--brain .comparison-label {
  color: var(--color-accent);
}

.comparison-title {
  font-size: var(--text-base);
  font-weight: 600;
  margin-bottom: var(--space-4);
  letter-spacing: -0.01em;
}

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

.comparison-list li {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: var(--space-2);
  max-width: none;
}

.comparison-list li::before {
  content: '—';
  color: var(--color-text-faint);
  flex-shrink: 0;
}

.comparison-card--brain .comparison-list li::before {
  content: '✦';
  color: var(--color-accent);
}

.comparison-card--brain .comparison-list li {
  color: var(--color-text);
}

@media (max-width: 640px) {
  .problem-comparison { grid-template-columns: 1fr; }
}

/* ============================================================
   ARCHITECTURES
   ============================================================ */
.arch-header {
  margin-bottom: var(--space-16);
}

.arch-heading {
  font-size: var(--text-xl);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: var(--space-4);
}

.arch-sub {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  max-width: 55ch;
  line-height: 1.7;
}

.arch-grid {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

/* Start visible — observer adds stagger on first-scroll-reveal */
.arch-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  display: grid;
  grid-template-columns: 1fr 380px;
  opacity: 1;
  transition: opacity 0.6s var(--ease), border-color 0.18s var(--ease), box-shadow 0.18s var(--ease);
}

/* JS-enhanced reveal: only applied when JS has set aria-hidden temporarily */
.arch-card.reveal-pending {
  opacity: 0;
}

.arch-card.visible {
  opacity: 1;
}

.arch-card:hover {
  border-color: rgba(212, 168, 83, 0.25);
  box-shadow: 0 8px 32px rgba(0,0,0,0.3), 0 0 0 1px rgba(212,168,83,0.1);
}

.arch-card-body {
  padding: clamp(var(--space-6), 4vw, var(--space-8));
  border-right: 1px solid var(--color-border-subtle);
}

.arch-number {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-accent);
  letter-spacing: 0.08em;
  margin-bottom: var(--space-3);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.arch-number::before {
  content: '';
  width: 12px;
  height: 1px;
  background: var(--color-accent);
}

.arch-name {
  font-size: var(--text-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-2);
  color: var(--color-text);
}

.arch-neuro {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  font-style: italic;
  margin-bottom: var(--space-6);
  padding-left: var(--space-4);
  border-left: 2px solid var(--color-border);
  line-height: 1.6;
  max-width: 50ch;
}

.arch-section-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-faint);
  margin-bottom: var(--space-2);
}

.arch-flaw {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
  line-height: 1.7;
  max-width: 56ch;
}

.arch-how {
  font-size: var(--text-xs);
  color: var(--color-text);
  line-height: 1.75;
  max-width: 56ch;
}

.arch-diagram {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-8);
  background: var(--color-surface-code);
  min-height: 200px;
}

@media (max-width: 900px) {
  .arch-card {
    grid-template-columns: 1fr;
  }
  .arch-card-body {
    border-right: none;
    border-bottom: 1px solid var(--color-border-subtle);
  }
  .arch-diagram {
    min-height: 160px;
  }
}

/* ============================================================
   PIPELINE SECTION
   ============================================================ */
.pipeline {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border-subtle);
  border-bottom: 1px solid var(--color-border-subtle);
}

.pipeline-heading {
  font-size: var(--text-xl);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: var(--space-4);
}

.pipeline-sub {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-12);
  max-width: 55ch;
  line-height: 1.7;
}

.pipeline-diagram {
  background: var(--color-surface-code);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: clamp(var(--space-8), 5vw, var(--space-12));
  overflow-x: auto;
}

/* ============================================================
   QUICK START
   ============================================================ */
.quickstart-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
}

.quickstart-heading {
  font-size: var(--text-xl);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: var(--space-4);
}

.quickstart-sub {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-10);
  max-width: 52ch;
  line-height: 1.7;
}

.code-block {
  background: var(--color-surface-code);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.code-block-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-surface-2);
}

.code-block-title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

.code-copy {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  border: 1px solid transparent;
}

.code-copy:hover {
  color: var(--color-accent);
  border-color: var(--color-border);
  background: var(--color-surface-offset);
}

.code-block pre {
  padding: var(--space-5) var(--space-6);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.7;
  color: var(--color-text);
}

.code-block code .c { color: var(--color-text-faint); font-style: italic; }  /* comments */
.code-block code .s { color: #9ece6a; }  /* strings */
.code-block code .k { color: #bb9af7; }  /* keywords */
.code-block code .f { color: #7dcfff; }  /* functions */
.code-block code .n { color: #e0af68; }  /* names/vars */
.code-block code .p { color: #89ddff; }  /* punctuation */
.code-block code .t { color: var(--color-accent); }  /* types */

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

/* ============================================================
   COMPARISON TABLE
   ============================================================ */
.comparison-table-section {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border-subtle);
  border-bottom: 1px solid var(--color-border-subtle);
}

.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
}

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

.compare-table thead {
  background: var(--color-surface-2);
}

.compare-table th {
  padding: var(--space-4) var(--space-5);
  text-align: left;
  font-weight: 600;
  color: var(--color-text);
  white-space: nowrap;
  border-bottom: 1px solid var(--color-border);
  letter-spacing: -0.01em;
}

.compare-table th:first-child {
  color: var(--color-text-muted);
  font-weight: 400;
  font-style: italic;
  width: 200px;
}

.compare-table th.col-mnemos {
  color: var(--color-accent);
}

.compare-table td {
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--color-border-subtle);
  color: var(--color-text-muted);
  vertical-align: middle;
}

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

.compare-table tr:hover td {
  background: var(--color-surface-offset);
}

.compare-table td:first-child {
  color: var(--color-text);
  font-weight: 500;
  font-size: var(--text-xs);
}

.check {
  color: var(--color-success);
  font-size: 1rem;
  display: inline-block;
}

.cross {
  color: var(--color-text-faint);
  font-size: 1rem;
  display: inline-block;
}

.partial {
  color: var(--color-accent);
  font-size: var(--text-xs);
  font-style: italic;
}

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
  padding-block: var(--space-16) var(--space-12);
  border-top: 1px solid var(--color-border-subtle);
}

.footer-inner {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-8);
  flex-wrap: wrap;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-2);
}

.footer-desc {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  max-width: 30ch;
  line-height: 1.6;
}

.footer-creator {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  margin-top: var(--space-2);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-links-heading {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-faint);
  margin-bottom: var(--space-2);
}

.footer-links a {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  transition: color var(--transition);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.footer-links a:hover { color: var(--color-accent); }

.footer-bottom {
  margin-top: var(--space-12);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.footer-bottom-text {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}

.footer-bottom-text a {
  color: var(--color-text-muted);
  transition: color var(--transition);
}

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

/* ============================================================
   DIVIDERS
   ============================================================ */
.divider {
  height: 1px;
  background: var(--color-divider);
  margin-block: var(--space-8);
}

/* ============================================================
   SKIP LINK
   ============================================================ */
.skip-link {
  position: absolute;
  top: -100px;
  left: var(--space-4);
  z-index: 999;
  font-size: var(--text-sm);
  padding: var(--space-2) var(--space-4);
  background: var(--color-accent);
  color: #0a0a0f;
  border-radius: var(--radius-md);
}

.skip-link:focus {
  top: var(--space-4);
}

/* ============================================================
   SVG ANIMATIONS
   ============================================================ */

/* Surprisal gate pulse */
@keyframes pulse-gate {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 1; }
}

@keyframes flow-in {
  0% { stroke-dashoffset: 60; }
  100% { stroke-dashoffset: 0; }
}

@keyframes glow-node {
  0%, 100% { filter: drop-shadow(0 0 2px var(--color-accent)); }
  50% { filter: drop-shadow(0 0 8px var(--color-accent)); }
}

@keyframes ripple-out {
  0% { stroke-opacity: 0; }
  30% { stroke-opacity: 0.8; }
  100% { stroke-opacity: 0; }
}

@keyframes drift-dot {
  0%   { cx: 90; cy: 90; }
  25%  { cx: 130; cy: 70; }
  50%  { cx: 160; cy: 110; }
  75%  { cx: 120; cy: 140; }
  100% { cx: 90; cy: 90; }
}

@keyframes compress-left {
  0%, 100% { opacity: 0.8; }
  50% { opacity: 0.3; }
}

@keyframes compress-right {
  0%, 100% { r: 8; }
  50% { r: 12; }
}

@keyframes energy-ring {
  0% { r: 12; stroke-opacity: 0.6; }
  100% { r: 28; stroke-opacity: 0; }
}

@keyframes mutable-write {
  0%   { opacity: 0.3; }
  40%  { opacity: 1; }
  60%  { opacity: 0.6; }
  100% { opacity: 0.3; }
}

@keyframes spread-energy {
  0%   { stroke-opacity: 0; stroke-dashoffset: 40; }
  30%  { stroke-opacity: 0.7; }
  100% { stroke-opacity: 0; stroke-dashoffset: 0; }
}