/* ==========================================================================
   Iris // KNN, Glitch design system
   Token-driven, WCAG 2.2 AA. Dark by default, light theme opt-in.
   See DESIGN.md for the rationale.
   ========================================================================== */

/* --- 1. Tokens --- */
:root {
  color-scheme: dark;

  /* surfaces */
  --color-surface-base:    #000000;
  --color-surface-raised:  #0a0a0a;
  --color-surface-overlay: #121212;
  --color-surface-inset:   #050505;
  --color-surface-nav:     rgba(0, 0, 0, 0.82);

  /* borders (Glitch #545454 is used here, where contrast rules don't apply) */
  --color-border:        #262626;
  --color-border-strong: #545454;

  /* text: all pass AA on #000 */
  --color-text-primary:   #f2f2f2;
  --color-text-secondary: #a6a6a6;
  --color-text-muted:     #8a8a8a;
  --color-text-inverse:   #000000;

  /* brand accent */
  --color-accent:        #82b440;
  --color-accent-strong: #6f9a37;
  --color-accent-hover:  #90c44e;
  --color-accent-soft:   rgba(130, 180, 64, 0.14);
  --color-accent-glow:   rgba(130, 180, 64, 0.35);
  --color-link:          #a8d46b;

  /* status */
  --color-danger:       #ff7070;
  --color-danger-soft:  rgba(255, 112, 112, 0.12);
  --color-warning:      #f2b544;
  --color-warning-soft: rgba(242, 181, 68, 0.12);

  /* categorical: validated for CVD on #000 */
  --color-setosa:     #74a636;
  --color-versicolor: #d9566f;
  --color-virginica:  #2f8fd6;

  /* glitch chroma split */
  --color-glitch-a: #82b440;
  --color-glitch-b: #d9566f;

  /* atmosphere: scanline darkening and the two noise speckles */
  --atmos-scanline: rgba(0, 0, 0, 0.16);
  --atmos-noise-a:  rgba(255, 255, 255, 0.028);
  --atmos-noise-b:  rgba(255, 255, 255, 0.018);

  /* heat ramp for the confusion matrix, as channels so alpha can vary */
  --heat-rgb: 130 180 64;

  /* the arrow drawn inside a select, tinted with the accent */
  --select-arrow: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M1 1l4 4 4-4' fill='none' stroke='%2382b440' stroke-width='1.5'/%3E%3C/svg%3E");

  /* type */
  --font-primary: "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --text-xs: 12px;
  --text-sm: 14px;
  --text-md: 16px;
  --text-lg: 20px;
  --text-xl: 26px;
  --text-2xl: clamp(28px, 4vw, 40px);
  --text-display: clamp(34px, 8vw, 84px);

  --leading-tight: 1.15;
  --leading-base: 1.5;
  --tracking-wide: 0.12em;

  /* spacing: 5px base */
  --space-1: 5px;
  --space-2: 10px;
  --space-3: 15px;
  --space-4: 20px;
  --space-5: 25px;
  --space-6: 30px;
  --space-8: 40px;
  --space-10: 50px;
  --space-12: 60px;
  --space-16: 80px;
  --space-20: 100px;

  --gutter: 16px;
  --container: 1200px;

  --radius-xs: 4px;
  --radius-sm: 6px;
  --radius-pill: 999px;

  --shadow-1: 0 2px 0 0 var(--color-accent-strong);
  --shadow-2: 0 4px 0 0 var(--color-accent-strong);
  --shadow-panel: 0 0 0 1px var(--color-border);
  --shadow-tooltip: 0 4px 16px rgba(0, 0, 0, 0.6);

  --motion-fast: 150ms;
  --motion-base: 250ms;
  --motion-slow: 600ms;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-glitch: steps(2, end);

  --tap: 44px;
  --nav-h: 60px;
}

/* Light theme. Same token names, re-pointed. Dark stays the default: light
   applies when the visitor picks it, or when the system asks for it and they
   have not picked anything. Every pair below was checked against WCAG AA. */
[data-theme="light"] {
  color-scheme: light;

  --color-surface-base:    #ffffff;
  --color-surface-raised:  #f6f6f4;
  --color-surface-overlay: #ececea;
  --color-surface-inset:   #fbfbfa;
  --color-surface-nav:     rgba(255, 255, 255, 0.86);

  --color-border:        #dcdcd8;
  --color-border-strong: #8f8f88;

  --color-text-primary:   #101010;
  --color-text-secondary: #4d4d4d;
  --color-text-muted:     #5f5f5f;
  --color-text-inverse:   #ffffff;

  --color-accent:        #4b7419;
  --color-accent-strong: #3a5a12;
  --color-accent-hover:  #3a5a12;
  --color-accent-soft:   rgba(75, 116, 25, 0.12);
  --color-accent-glow:   rgba(75, 116, 25, 0.35);
  --color-link:          #41641a;

  --color-danger:       #b3261e;
  --color-danger-soft:  rgba(179, 38, 30, 0.1);
  --color-warning:      #8a5a00;
  --color-warning-soft: rgba(138, 90, 0, 0.12);

  --color-setosa:     #4b6f1f;
  --color-versicolor: #a8324a;
  --color-virginica:  #1f6aa5;

  --color-glitch-a: #4b7419;
  --color-glitch-b: #a8324a;

  --atmos-scanline: rgba(0, 0, 0, 0.045);
  --atmos-noise-a:  rgba(0, 0, 0, 0.022);
  --atmos-noise-b:  rgba(0, 0, 0, 0.014);

  --heat-rgb: 75 116 25;

  --select-arrow: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M1 1l4 4 4-4' fill='none' stroke='%234b7419' stroke-width='1.5'/%3E%3C/svg%3E");

  --shadow-tooltip: 0 4px 16px rgba(0, 0, 0, 0.18);
}

/* --- 2. Reset --- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 10px); -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-primary);
  font-size: var(--text-md);
  font-weight: 400;
  line-height: var(--leading-base);
  color: var(--color-text-primary);
  background: var(--color-surface-base);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
h1, h2, h3, p, ul, ol, dl, dd, figure, pre { margin: 0; }
ul, ol { padding: 0; list-style: none; }
button, input, select { font: inherit; color: inherit; }
button { cursor: pointer; }
a { color: var(--color-link); text-underline-offset: 3px; }
a:hover { color: var(--color-text-primary); }
code, pre { font-family: var(--font-mono); }
img, svg { display: block; max-width: 100%; }
[hidden] { display: none !important; }

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0);
  white-space: nowrap; border: 0;
  text-transform: none; letter-spacing: 0;
}

/* Focus: one rule for everything interactive */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-xs);
}
::selection { background: var(--color-accent); color: var(--color-text-inverse); }

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.skip-link {
  position: fixed; top: var(--space-2); left: var(--space-2);
  z-index: 100;
  padding: var(--space-2) var(--space-3);
  background: var(--color-accent);
  color: var(--color-text-inverse);
  font-weight: 700; text-decoration: none;
  border-radius: var(--radius-xs);
  transform: translateY(-200%);
  transition: transform var(--motion-fast);
}
.skip-link:focus { transform: translateY(0); }

/* --- 3. Atmosphere (scanlines + noise) --- */
.scanlines, .noise {
  position: fixed; inset: 0;
  pointer-events: none;
  z-index: 50;
}
.scanlines {
  background: repeating-linear-gradient(
    to bottom,
    transparent 0 2px,
    var(--atmos-scanline) 2px 3px
  );
  opacity: 0.7;
}
.noise {
  background-image:
    radial-gradient(var(--atmos-noise-a) 1px, transparent 1px),
    radial-gradient(var(--atmos-noise-b) 1px, transparent 1px);
  background-size: 7px 7px, 11px 11px;
  background-position: 0 0, 3px 5px;
  animation: noise-drift 1.2s steps(4) infinite;
}
@keyframes noise-drift {
  0%   { background-position: 0 0, 3px 5px; }
  25%  { background-position: -2px 1px, 5px 2px; }
  50%  { background-position: 1px -3px, 2px 7px; }
  75%  { background-position: -1px 2px, 6px 4px; }
  100% { background-position: 0 0, 3px 5px; }
}

/* --- 4. Navigation --- */
.nav {
  position: sticky; top: 0; z-index: 60;
  height: var(--nav-h);
  background: var(--color-surface-nav);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: border-bottom-color var(--motion-base);
}
.nav-inner {
  max-width: var(--container);
  height: 100%;
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--space-4);
}
.brand {
  display: inline-flex; align-items: center; gap: var(--space-2);
  color: var(--color-text-primary);
  text-decoration: none;
  font-weight: 700; letter-spacing: 0.08em;
  font-size: var(--text-md);
  min-height: var(--tap);
}
.brand-mark {
  width: 10px; height: 10px;
  background: var(--color-accent);
  box-shadow: 0 0 12px var(--color-accent-glow);
  animation: pulse 2.4s ease-in-out infinite;
}
.brand-sep { color: var(--color-accent); }
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%      { opacity: 0.55; transform: scale(0.8); }
}

.nav-list { position: relative; display: flex; gap: var(--space-1); }
.nav-link {
  display: inline-flex; align-items: center;
  min-height: var(--tap);
  padding: 0 var(--space-3);
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  border-radius: var(--radius-xs);
  transition: color var(--motion-fast), background var(--motion-fast);
}
.nav-link:hover { color: var(--color-text-primary); background: var(--color-surface-overlay); }
.nav-link:active { background: var(--color-accent-soft); }
.nav-link.is-active { color: var(--color-text-primary); }
.nav.is-scrolled { border-bottom-color: var(--color-accent-glow); }
/* one underline that slides between the active links */
.nav-indicator {
  position: absolute; left: 0; bottom: 4px;
  height: 2px; width: 0;
  background: var(--color-accent);
  border-radius: var(--radius-xs);
  opacity: 0;
  transform-origin: left center;
  transition: transform var(--motion-base) var(--ease-out), width var(--motion-base) var(--ease-out), opacity var(--motion-fast);
  pointer-events: none;
}
.nav-indicator.is-on { opacity: 1; }
.nav-link-ext::after {
  content: "↗"; margin-left: 4px; color: var(--color-accent);
}

.nav-toggle {
  display: none;
  align-items: center; gap: var(--space-2);
  min-height: var(--tap); min-width: var(--tap);
  padding: 0 var(--space-2);
  background: transparent;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-xs);
  color: var(--color-text-primary);
  font-size: var(--text-sm); font-weight: 700;
}
.nav-toggle:hover { border-color: var(--color-accent); color: var(--color-accent); background: var(--color-accent-soft); }
.nav-toggle-icon { position: relative; width: 18px; height: 12px; display: block; }
.nav-toggle-bar {
  position: absolute; left: 0; width: 18px; height: 2px;
  background: currentColor;
  transition: transform var(--motion-base) var(--ease-out);
}
.nav-toggle-bar:first-child { top: 1px; }
.nav-toggle-bar:last-child { bottom: 1px; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:first-child { transform: translateY(4px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:last-child { transform: translateY(-4px) rotate(-45deg); }

.nav-right { display: flex; align-items: center; gap: var(--space-2); }
.theme-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  width: var(--tap); height: var(--tap);
  padding: 0;
  background: transparent;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-xs);
  color: var(--color-text-secondary);
  transition: color var(--motion-fast), border-color var(--motion-fast), background var(--motion-fast);
}
.theme-toggle:hover { border-color: var(--color-accent); color: var(--color-accent); background: var(--color-accent-soft); }
.theme-toggle:active { transform: translateY(1px); }
.theme-icon { width: 18px; height: 18px; transition: transform var(--motion-base) var(--ease-out); }
.theme-icon-sun { fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; }
.theme-icon-moon { fill: currentColor; stroke: none; }
.theme-toggle:hover .theme-icon { transform: rotate(25deg); }
/* the button shows the theme it switches to */
.theme-icon-moon { display: none; }
[data-theme="light"] .theme-icon-sun { display: none; }
[data-theme="light"] .theme-icon-moon { display: block; }

@media (max-width: 767px) {
  .nav-toggle { display: inline-flex; }
  .nav-menu {
    position: absolute; top: var(--nav-h); left: 0; right: 0;
    background: var(--color-surface-raised);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-2) var(--gutter) var(--space-3);
    transform: translateY(-8px);
    opacity: 0; visibility: hidden;
    transition: opacity var(--motion-base), transform var(--motion-base) var(--ease-out), visibility 0s var(--motion-base);
  }
  .nav-menu.is-open {
    opacity: 1; visibility: visible; transform: translateY(0);
    transition: opacity var(--motion-base), transform var(--motion-base) var(--ease-out);
  }
  .nav-list { flex-direction: column; gap: 0; }
  .nav-link { width: 100%; min-height: 48px; }
  .nav-indicator { display: none; }
  .nav-link.is-active { box-shadow: inset 3px 0 0 var(--color-accent); }
}

/* --- 5. Buttons --- */
.btn {
  position: relative;
  display: inline-flex; align-items: center; justify-content: center;
  gap: var(--space-2);
  min-height: var(--tap);
  padding: 0 var(--space-5);
  border: 1px solid transparent;
  border-radius: var(--radius-xs);
  font-size: var(--text-sm); font-weight: 700;
  letter-spacing: 0.01em;
  text-decoration: none;
  transition: transform var(--motion-fast), box-shadow var(--motion-fast), background var(--motion-fast), color var(--motion-fast), border-color var(--motion-fast);
  user-select: none;
}
.btn-primary {
  background: var(--color-accent);
  color: var(--color-text-inverse);
  box-shadow: var(--shadow-1);
}
.btn-primary:hover { background: var(--color-accent-hover); box-shadow: var(--shadow-2); transform: translateY(-2px); color: var(--color-text-inverse); }
.btn-primary:active { transform: translateY(1px); box-shadow: none; }
.btn-ghost {
  background: transparent;
  color: var(--color-text-primary);
  border-color: var(--color-border-strong);
}
.btn-ghost:hover { border-color: var(--color-accent); color: var(--color-accent); background: var(--color-accent-soft); }
.btn-ghost:active { background: transparent; }
.btn:disabled, .btn[aria-disabled="true"] {
  opacity: 0.45; cursor: not-allowed; transform: none; box-shadow: none;
}
.btn-block { width: 100%; }
.btn-sm { min-height: 40px; padding: 0 var(--space-3); font-size: var(--text-xs); }
.btn-arrow { transition: transform var(--motion-fast); }
.btn:hover .btn-arrow { transform: translateX(4px); }

.btn-spinner {
  display: none;
  width: 16px; height: 16px;
  border: 2px solid rgba(0,0,0,0.25);
  border-top-color: var(--color-text-inverse);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
.btn-ghost .btn-spinner { border-color: var(--color-accent-soft); border-top-color: var(--color-accent); }
.btn.is-loading { pointer-events: none; }
.btn.is-loading .btn-spinner { display: inline-block; }
@keyframes spin { to { transform: rotate(360deg); } }

/* --- 6. Hero --- */
.hero {
  position: relative;
  padding: var(--space-16) 0 var(--space-12);
  border-bottom: 1px solid var(--color-border);
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute; inset: 0;
  background:
    linear-gradient(var(--color-border) 1px, transparent 1px) 0 0 / 60px 60px,
    linear-gradient(90deg, var(--color-border) 1px, transparent 1px) 0 0 / 60px 60px;
  mask-image: radial-gradient(ellipse 70% 80% at 50% 0%, #000 20%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 70% 80% at 50% 0%, #000 20%, transparent 100%);
  opacity: 0.55;
  pointer-events: none;
}
.hero::after {
  content: "";
  position: absolute; top: -200px; left: 50%;
  width: 700px; height: 500px;
  transform: translateX(-50%);
  background: radial-gradient(closest-side, var(--color-accent-soft), transparent);
  pointer-events: none;
}
.hero .container { position: relative; }

.eyebrow {
  display: flex; width: fit-content; align-items: center; gap: var(--space-2);
  font-size: var(--text-sm); font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--color-accent);
  margin-bottom: var(--space-4);
}
.eyebrow-dot {
  width: 8px; height: 8px; background: currentColor;
  animation: pulse 1.6s ease-in-out infinite;
}

.hero-title {
  display: block;
  font-size: var(--text-display);
  font-weight: 700;
  line-height: 1.02;
  letter-spacing: -0.02em;
  max-width: 14ch;
  margin-bottom: var(--space-5);
  text-wrap: balance;
}
/* Each word rises out of its own clip mask; the h1 itself stays put so the
   glitch layers line up. JS wraps the words and sets --i for the stagger. */
.hero-title.reveal { opacity: 1; transform: none; }
.hero-title .w { display: inline-block; clip-path: inset(-0.1em 0 -0.25em 0); }
.hero-title .w-in {
  display: inline-block;
  transform: translateY(115%);
  transition: transform var(--motion-slow) var(--ease-out);
  transition-delay: calc(var(--i, 0) * 90ms);
}
.hero-title.is-visible .w-in { transform: none; }
.lede {
  max-width: 62ch;
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-6);
}
.hero-actions {
  display: flex; flex-wrap: wrap; gap: var(--space-3);
  margin-bottom: var(--space-10);
}

.stat-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  background: var(--color-border);
  border: 1px solid var(--color-border);
}
.stat {
  background: var(--color-surface-base);
  padding: var(--space-4);
  transition: background var(--motion-base);
}
.stat:hover { background: var(--color-surface-raised); }
.stat dt {
  font-size: var(--text-xs); text-transform: uppercase; letter-spacing: var(--tracking-wide);
  color: var(--color-text-muted);
  margin-bottom: var(--space-1);
}
.stat dd {
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text-primary);
  font-variant-numeric: tabular-nums;
}
.stat .unit { color: var(--color-accent); font-size: 0.7em; margin-left: 2px; }

/* --- 7. Glitch text --- */
.glitch { position: relative; display: inline-block; }
.glitch::before, .glitch::after {
  content: attr(data-text);
  position: absolute; inset: 0;
  overflow: hidden;
  pointer-events: none;
  opacity: 0;
}
.glitch::before {
  color: var(--color-glitch-a);
  left: 3px;
  text-shadow: -2px 0 var(--color-glitch-b);
  animation: glitch-a 3.6s infinite var(--ease-glitch);
}
.glitch::after {
  color: var(--color-glitch-b);
  left: -3px;
  text-shadow: 2px 0 var(--color-glitch-a);
  animation: glitch-b 3.6s infinite var(--ease-glitch);
  animation-delay: 0.2s;
}
@keyframes glitch-a {
  0%, 86%, 100% { opacity: 0; clip-path: inset(0 0 100% 0); transform: translate(0); }
  87% { opacity: 1; clip-path: inset(8% 0 70% 0);  transform: translate(-4px, -2px); }
  89% { opacity: 1; clip-path: inset(45% 0 30% 0); transform: translate(5px, 1px); }
  91% { opacity: 1; clip-path: inset(70% 0 5% 0);  transform: translate(-3px, 2px); }
  93% { opacity: 1; clip-path: inset(20% 0 55% 0); transform: translate(4px, -1px); }
  95% { opacity: 0; clip-path: inset(0 0 100% 0); }
}
@keyframes glitch-b {
  0%, 86%, 100% { opacity: 0; clip-path: inset(100% 0 0 0); transform: translate(0); }
  88% { opacity: 1; clip-path: inset(55% 0 20% 0); transform: translate(4px, 1px); }
  90% { opacity: 1; clip-path: inset(10% 0 75% 0); transform: translate(-5px, -1px); }
  92% { opacity: 1; clip-path: inset(35% 0 40% 0); transform: translate(3px, 2px); }
  94% { opacity: 1; clip-path: inset(80% 0 2% 0);  transform: translate(-4px, 0); }
  96% { opacity: 0; clip-path: inset(100% 0 0 0); }
}
.glitch-flash.is-glitching::before,
.glitch-flash.is-glitching::after { animation-duration: 0.5s; animation-iteration-count: 1; }
.glitch-flash.is-glitching::before { animation-name: glitch-a-once; }
.glitch-flash.is-glitching::after  { animation-name: glitch-b-once; }
@keyframes glitch-a-once {
  0%   { opacity: 1; clip-path: inset(8% 0 70% 0);  transform: translate(-4px, -2px); }
  30%  { opacity: 1; clip-path: inset(45% 0 30% 0); transform: translate(5px, 1px); }
  60%  { opacity: 1; clip-path: inset(70% 0 5% 0);  transform: translate(-3px, 2px); }
  100% { opacity: 0; clip-path: inset(0 0 100% 0); }
}
@keyframes glitch-b-once {
  0%   { opacity: 1; clip-path: inset(55% 0 20% 0); transform: translate(4px, 1px); }
  30%  { opacity: 1; clip-path: inset(10% 0 75% 0); transform: translate(-5px, -1px); }
  60%  { opacity: 1; clip-path: inset(35% 0 40% 0); transform: translate(3px, 2px); }
  100% { opacity: 0; clip-path: inset(100% 0 0 0); }
}

/* --- 8. Sections & panels --- */
.section { padding: var(--space-16) 0; }
.section-alt { background: var(--color-surface-raised); border-block: 1px solid var(--color-border); }
.section-head { max-width: 70ch; margin-bottom: var(--space-8); }
.section-index {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-accent);
  letter-spacing: var(--tracking-wide);
  margin-bottom: var(--space-2);
}
.section-index::after { content: " ////"; color: var(--color-border-strong); }
.section-title {
  font-size: var(--text-2xl);
  font-weight: 700; line-height: var(--leading-tight);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-3);
  text-wrap: balance;
}
.section-sub { color: var(--color-text-secondary); max-width: 62ch; }

.panel {
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  padding: var(--space-5);
  position: relative;
  min-width: 0;
  transition: border-color var(--motion-base);
}
.section-alt .panel { background: var(--color-surface-base); }
.panel:hover { border-color: var(--color-border-strong); }
.panel::before {
  content: "";
  position: absolute; top: -1px; left: -1px;
  width: 14px; height: 14px;
  border-top: 2px solid var(--color-accent);
  border-left: 2px solid var(--color-accent);
  opacity: 0; transition: opacity var(--motion-base);
}
.panel:hover::before, .panel:focus-within::before { opacity: 1; }

.panel-head {
  display: flex; flex-wrap: wrap; align-items: flex-start; justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}
.panel-title { font-size: var(--text-md); font-weight: 700; }
.panel-sub { font-size: var(--text-sm); color: var(--color-text-secondary); margin-top: 2px; }
.block-title {
  font-size: var(--text-sm); font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-2);
}
.block-note { text-transform: none; letter-spacing: 0; font-weight: 400; color: var(--color-text-secondary); }

/* --- 9. Predict layout --- */
.predict-grid {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: var(--space-4);
}
.panel-form { grid-row: span 2; }
.panel-scatter { min-width: 0; }
@media (max-width: 1023px) {
  .predict-grid { grid-template-columns: minmax(0, 1fr); }
  .panel-form { grid-row: auto; }
}

/* --- 10. Form fields --- */
.fieldset { border: 0; padding: 0; margin: 0 0 var(--space-5); min-width: 0; }
.legend {
  font-size: var(--text-md); font-weight: 700;
  padding: 0; margin-bottom: var(--space-1);
}
.legend-unit { font-weight: 400; color: var(--color-text-muted); font-size: var(--text-sm); margin-left: var(--space-1); }
.hint { font-size: var(--text-sm); color: var(--color-text-muted); margin-bottom: var(--space-4); }

.field { padding: var(--space-4) 0; border-top: 1px solid var(--color-border); }
.field-row {
  display: flex; align-items: flex-end; justify-content: space-between;
  gap: var(--space-2);
  margin-bottom: var(--space-1);
}
.field-label { font-size: var(--text-sm); font-weight: 700; }
.field-number-wrap {
  display: inline-flex; align-items: center;
  background: var(--color-surface-inset);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-xs);
  padding-right: var(--space-2);
  transition: border-color var(--motion-fast), box-shadow var(--motion-fast);
}
.field-number-wrap:hover { border-color: var(--color-text-muted); }
.field-number-wrap:focus-within { border-color: var(--color-accent); box-shadow: 0 0 0 3px var(--color-accent-soft); }
.field.is-tick .field-number-wrap { border-color: var(--color-accent); }
.field.is-tick .field-number { color: var(--color-accent); }
.field-number { transition: color var(--motion-fast); }
.field.is-invalid .field-number-wrap { border-color: var(--color-danger); }
.field-number {
  width: 64px; min-height: 36px;
  padding: 0 var(--space-2);
  background: transparent; border: 0;
  font-family: var(--font-mono); font-size: var(--text-sm); font-weight: 700;
  text-align: right;
  color: var(--color-text-primary);
  -moz-appearance: textfield;
}
.field-number:focus-visible { outline: none; }
.field-number::-webkit-outer-spin-button, .field-number::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.field-unit { font-size: var(--text-xs); color: var(--color-text-muted); }

.field-range-wrap { display: flex; align-items: center; gap: var(--space-2); }
.field-bound { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-text-muted); width: 28px; flex-shrink: 0; }
.field-bound:last-child { text-align: right; }

.field-range {
  --pct: 0%;
  flex: 1; min-width: 0;
  height: var(--tap);
  margin: 0;
  background: transparent;
  -webkit-appearance: none; appearance: none;
  cursor: pointer;
}
.field-range::-webkit-slider-runnable-track {
  height: 4px;
  background: linear-gradient(90deg, var(--color-accent) var(--pct), var(--color-border-strong) var(--pct));
  border-radius: var(--radius-xs);
}
.field-range::-moz-range-track {
  height: 4px; background: var(--color-border-strong); border-radius: var(--radius-xs);
}
.field-range::-moz-range-progress { height: 4px; background: var(--color-accent); border-radius: var(--radius-xs); }
.field-range::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 20px; height: 20px;
  margin-top: -8px;
  background: var(--color-surface-base);
  border: 3px solid var(--color-accent);
  border-radius: 50%;
  box-shadow: 0 0 0 0 var(--color-accent-glow);
  transition: transform var(--motion-fast), box-shadow var(--motion-fast);
}
.field-range::-moz-range-thumb {
  width: 14px; height: 14px;
  background: var(--color-surface-base);
  border: 3px solid var(--color-accent);
  border-radius: 50%;
  transition: transform var(--motion-fast), box-shadow var(--motion-fast);
}
.field-range:hover::-webkit-slider-thumb, .field-range:active::-webkit-slider-thumb { transform: scale(1.15); box-shadow: 0 0 0 6px var(--color-accent-soft); }
.field-range:hover::-moz-range-thumb, .field-range:active::-moz-range-thumb { transform: scale(1.15); box-shadow: 0 0 0 6px var(--color-accent-soft); }
.field-range:focus-visible { outline: none; }
.field-range:focus-visible::-webkit-slider-thumb { outline: 2px solid var(--color-accent); outline-offset: 3px; }
.field-range:focus-visible::-moz-range-thumb { outline: 2px solid var(--color-accent); outline-offset: 3px; }
.field-range:disabled { opacity: 0.4; cursor: not-allowed; }

.field-error { font-size: var(--text-xs); color: var(--color-danger); margin-top: var(--space-1); }

/* presets */
.presets { margin-bottom: var(--space-5); }
.presets-label { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: var(--tracking-wide); color: var(--color-text-muted); margin-bottom: var(--space-2); }
.preset-row { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.chip {
  display: inline-flex; align-items: center; gap: var(--space-2);
  min-height: 40px;
  padding: 0 var(--space-3);
  background: var(--color-surface-inset);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-xs);
  font-size: var(--text-sm);
  color: var(--color-text-primary);
  transition: border-color var(--motion-fast), background var(--motion-fast), transform var(--motion-fast);
}
.chip:hover { border-color: var(--color-accent); background: var(--color-accent-soft); transform: translateY(-1px); }
.chip:active { transform: translateY(0); }
.chip.is-active { border-color: var(--color-accent); box-shadow: inset 0 0 0 1px var(--color-accent); }
.chip-dot, .legend-swatch {
  width: 10px; height: 10px; border-radius: 50%;
  flex-shrink: 0; display: inline-block;
}
.legend-swatch { margin-right: var(--space-2); vertical-align: -1px; }
.dot-setosa     { background: var(--color-setosa); }
.dot-versicolor { background: var(--color-versicolor); }
.dot-virginica  { background: var(--color-virginica); }
.legend-query   { background: transparent; border: 2px solid var(--color-text-primary); }

/* switch */
.form-footer { display: flex; flex-direction: column; gap: var(--space-3); }
.switch { display: inline-flex; align-items: center; gap: var(--space-2); cursor: pointer; min-height: var(--tap); }
.switch input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.switch-track {
  position: relative; width: 40px; height: 22px; flex-shrink: 0;
  background: var(--color-border-strong);
  border-radius: var(--radius-pill);
  transition: background var(--motion-fast);
}
.switch-thumb {
  position: absolute; top: 3px; left: 3px;
  width: 16px; height: 16px; border-radius: 50%;
  background: var(--color-text-primary);
  transition: transform var(--motion-base) var(--ease-out);
}
.switch input:checked + .switch-track { background: var(--color-accent); }
.switch input:checked + .switch-track .switch-thumb { transform: translateX(18px); background: var(--color-text-inverse); }
.switch input:focus-visible + .switch-track { outline: 2px solid var(--color-accent); outline-offset: 3px; }
.switch-label { font-size: var(--text-sm); color: var(--color-text-secondary); }
.switch:hover .switch-label { color: var(--color-text-primary); }

/* --- 11. Result panel --- */
.panel-result { min-height: 320px; display: flex; flex-direction: column; }
.panel-result[data-state="loading"] { animation: panel-pulse 1s ease-in-out infinite; }
@keyframes panel-pulse { 50% { border-color: var(--color-accent); } }
/* a thin line runs along the top edge when a new prediction lands */
.panel-result::before {
  content: ""; position: absolute; top: -1px; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, transparent, var(--species-color, var(--color-accent)), transparent) no-repeat;
  background-size: 35% 100%; background-position: -40% 0;
  opacity: 0; pointer-events: none;
}
.panel-result.is-fresh { border-color: var(--species-color, var(--color-accent)); }
.panel-result.is-fresh::before { animation: result-sweep 0.7s var(--ease-out) both; }
@keyframes result-sweep { from { opacity: 1; background-position: -40% 0; } to { opacity: 1; background-position: 140% 0; } }

.result-empty {
  flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: center;
  text-align: center; padding: var(--space-8) var(--space-4);
  color: var(--color-text-secondary);
}
.empty-glyph { display: flex; gap: 6px; margin-bottom: var(--space-4); }
.empty-glyph span {
  width: 8px; height: 28px; background: var(--color-border-strong);
  animation: bars 1.4s ease-in-out infinite;
}
.empty-glyph span:nth-child(2) { animation-delay: 0.15s; }
.empty-glyph span:nth-child(3) { animation-delay: 0.3s; }
@keyframes bars { 50% { transform: scaleY(0.4); background: var(--color-accent); } }
.empty-title { font-weight: 700; color: var(--color-text-primary); margin-bottom: var(--space-1); }
.empty-copy { font-size: var(--text-sm); max-width: 32ch; }

.result-error {
  flex: 1; display: flex; flex-direction: column; align-items: flex-start; justify-content: center;
  gap: var(--space-2);
  padding: var(--space-4);
  border: 1px solid var(--color-danger);
  background: var(--color-danger-soft);
  border-radius: var(--radius-xs);
}
.error-title { font-weight: 700; color: var(--color-danger); }
.error-copy { font-size: var(--text-sm); color: var(--color-text-secondary); }

.result-body { animation: fade-up var(--motion-slow) var(--ease-out); }
@keyframes fade-up { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }

.result-head {
  display: flex; justify-content: space-between; align-items: flex-start; gap: var(--space-4);
  margin-bottom: var(--space-5);
}
.result-kicker { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: var(--tracking-wide); color: var(--color-text-muted); }
.result-name {
  font-size: var(--text-2xl); font-weight: 700; line-height: 1.1;
  color: var(--species-color, var(--color-accent));
  margin: var(--space-1) 0;
}
.result-summary { font-size: var(--text-sm); color: var(--color-text-secondary); max-width: 36ch; }

.ring { position: relative; width: 120px; height: 120px; flex-shrink: 0; }
.ring svg { width: 100%; height: 100%; transform: rotate(-90deg); }
.ring-track { fill: none; stroke: var(--color-border); stroke-width: 8; }
.ring-fill {
  fill: none; stroke: var(--species-color, var(--color-accent)); stroke-width: 8;
  stroke-linecap: butt;
  stroke-dasharray: 326.7;
  stroke-dashoffset: 326.7;
  transition: stroke-dashoffset 0.9s var(--ease-out), stroke var(--motion-base);
}
.ring-text {
  position: absolute; inset: 0;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  font-family: var(--font-mono); line-height: 1;
}
.ring-value { font-size: 26px; font-weight: 700; font-variant-numeric: tabular-nums; }
.ring-unit { font-size: var(--text-xs); color: var(--color-text-muted); }
.ring-label { font-family: var(--font-primary); font-size: 10px; text-transform: uppercase; letter-spacing: 0.1em; color: var(--color-text-muted); margin-top: 4px; }

.warnings {
  display: flex; flex-direction: column; gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  margin-bottom: var(--space-4);
  border-left: 3px solid var(--color-warning);
  background: var(--color-warning-soft);
  font-size: var(--text-sm); color: var(--color-text-secondary);
}
.warnings p::before { content: "⚠ "; color: var(--color-warning); }

.prob-block { margin-bottom: var(--space-5); }
.prob-list { display: flex; flex-direction: column; gap: var(--space-2); }
.prob-row { display: grid; grid-template-columns: 96px 1fr 48px; align-items: center; gap: var(--space-2); font-size: var(--text-sm); }
.prob-name { display: inline-flex; align-items: center; text-transform: capitalize; }
.prob-track { height: 8px; background: var(--color-border); border-radius: var(--radius-xs); overflow: hidden; }
.prob-fill {
  height: 100%; width: 0;
  border-radius: 0 var(--radius-xs) var(--radius-xs) 0;
  transition: width 0.8s var(--ease-out);
}
.prob-value { font-family: var(--font-mono); text-align: right; color: var(--color-text-secondary); font-variant-numeric: tabular-nums; }
.prob-row.is-winner .prob-value { color: var(--color-text-primary); font-weight: 700; }

.neighbors-block { margin-bottom: var(--space-4); }
.result-detail { font-size: var(--text-sm); color: var(--color-text-secondary); border-top: 1px solid var(--color-border); padding-top: var(--space-3); }

/* --- 12. Tables --- */
.table-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; margin-inline: calc(var(--space-2) * -1); padding-inline: var(--space-2); }
.table { width: 100%; border-collapse: collapse; font-size: var(--text-sm); min-width: 320px; }
.table th, .table td { padding: var(--space-2); text-align: left; border-bottom: 1px solid var(--color-border); white-space: nowrap; }
.table thead th { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.08em; color: var(--color-text-muted); font-weight: 700; }
.table tbody th { font-weight: 400; text-transform: capitalize; }
.table tbody tr { transition: background var(--motion-fast); }
.table tbody tr:hover { background: var(--color-surface-overlay); }
.table .num { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
.table tr.is-match td, .table tr.is-match th { color: var(--color-text-primary); }
.table tr.is-other td, .table tr.is-other th { color: var(--color-text-muted); }

.mini-stats {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--space-3);
  margin-top: var(--space-4); padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
}
.mini-stats dt { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.08em; color: var(--color-text-muted); }
.mini-stats dd { font-family: var(--font-mono); font-size: var(--text-sm); font-weight: 700; margin-top: 2px; }

/* --- 13. Charts --- */
.chart { width: 100%; position: relative; }
.chart svg { width: 100%; height: auto; overflow: visible; }
.chart .grid line { stroke: var(--color-border); stroke-width: 1; }
.chart .axis line, .chart .axis path { stroke: var(--color-border-strong); stroke-width: 1; }
.chart .axis text, .chart .tick text { fill: var(--color-text-muted); font-family: var(--font-mono); font-size: 11px; }
.chart .axis-label { fill: var(--color-text-secondary); font-family: var(--font-primary); font-size: 12px; }
.chart .series-line { fill: none; stroke: var(--color-accent); stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.chart .series-area { fill: var(--color-accent-soft); }
.chart .marker { fill: var(--color-surface-base); stroke: var(--color-accent); stroke-width: 2; transition: r var(--motion-fast); }
.chart .marker:hover, .chart .marker.is-active { r: 6; }
.chart .marker-chosen { fill: var(--color-accent); }
.chart .marker-best { stroke: var(--color-text-primary); }
.chart .ref-line { stroke: var(--color-border-strong); stroke-dasharray: 4 4; }
.chart .ref-label { fill: var(--color-text-secondary); font-size: 11px; font-family: var(--font-mono); }
.chart .crosshair { stroke: var(--color-border-strong); stroke-dasharray: 3 3; pointer-events: none; }
.chart .hit { fill: transparent; cursor: crosshair; }
.chart .dot { stroke: var(--color-surface-base); stroke-width: 2; transition: opacity var(--motion-fast), r var(--motion-fast); }
.chart .dot.is-dim { opacity: 0.25; }
/* dots sweep in left to right the first time the panel is on screen */
.chart .dot { transform-box: fill-box; transform-origin: center; }
.chart .dots.is-pending .dot { opacity: 0; transform: scale(0.3); }
.chart .dots.is-sweeping .dot { transition: opacity 0.5s var(--ease-out), transform 0.5s var(--ease-out); }
.chart .dot:hover { r: 6; }
.chart .query {
  fill: transparent; stroke: var(--color-text-primary); stroke-width: 2.5;
  transform-box: fill-box; transform-origin: center;
  animation: query-in 0.6s var(--ease-out);
}
.chart .query-pulse {
  fill: none; stroke: var(--color-text-primary); stroke-width: 1.5;
  transform-box: fill-box; transform-origin: center;
  animation: ripple 1.8s ease-out infinite;
}
@keyframes query-in { from { transform: scale(0); } to { transform: scale(1); } }
@keyframes ripple { 0% { transform: scale(0.6); opacity: 0.9; } 100% { transform: scale(2.4); opacity: 0; } }
.chart .bar { transition: opacity var(--motion-fast); }
.chart .bar:hover { opacity: 0.8; }
.chart .bar-label { fill: var(--color-text-secondary); font-family: var(--font-mono); font-size: 11px; text-anchor: middle; }

.legend { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-top: var(--space-3); font-size: var(--text-sm); color: var(--color-text-secondary); text-transform: capitalize; }
.legend li { display: inline-flex; align-items: center; }

/* confusion matrix */
.cm { display: grid; grid-template-columns: minmax(0, auto) repeat(3, minmax(0, 1fr)); gap: 2px; font-size: var(--text-sm); min-width: 0; }
.cm-row { display: contents; }
.cm-corner { background: transparent; }
.cm-head {
  padding: var(--space-2) var(--space-1);
  font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--color-text-muted); text-align: center;
  display: flex; align-items: flex-end; justify-content: center;
}
.cm-row-head { padding: var(--space-2) var(--space-2) var(--space-2) 0; color: var(--color-text-muted); font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.06em; display: flex; align-items: center; justify-content: flex-end; text-align: right; }
.cm-cell {
  position: relative;
  min-height: 64px;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  background: rgb(var(--heat-rgb) / calc(0.05 + var(--v, 0) * 0.6));
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  font-family: var(--font-mono); font-weight: 700; font-size: var(--text-lg);
  transition: transform var(--motion-fast), border-color var(--motion-fast);
  cursor: default;
}
.cm-cell:hover, .cm-cell:focus-visible { transform: scale(1.03); border-color: var(--color-accent); z-index: 1; }
/* cells pop in one at a time once the panel is on screen; the diagonal flashes once after */
.cm-cell.is-pending { opacity: 0; transform: scale(0.92); }
.cm-cell.is-entering { transition: opacity var(--motion-slow) var(--ease-out), transform var(--motion-slow) var(--ease-out); }
.cm-cell::after {
  content: ""; position: absolute; inset: 0; border-radius: inherit;
  background: var(--color-accent); opacity: 0; pointer-events: none;
}
.cm-cell.is-flash::after { animation: cm-flash 0.7s var(--ease-out) both; animation-delay: var(--flash-delay, 0ms); }
@keyframes cm-flash { 0% { opacity: 0; } 35% { opacity: 0.4; } 100% { opacity: 0; } }
.cm-cell small { font-family: var(--font-primary); font-weight: 400; font-size: 10px; color: inherit; text-transform: uppercase; letter-spacing: 0.06em; margin-top: 2px; }
.cm-cell.is-diag { color: var(--color-text-primary); }
.cm-cell.is-off { color: var(--color-text-secondary); }
.cm-cell.is-off[data-v="0"] { color: var(--color-text-muted); }
.cm-caption { text-align: center; font-size: var(--text-xs); color: var(--color-text-muted); padding-top: var(--space-2); }

/* tabs */
.tabs { display: flex; flex-wrap: wrap; gap: var(--space-1); border: 1px solid var(--color-border); padding: 3px; border-radius: var(--radius-xs); }
.tab {
  min-height: 34px; padding: 0 var(--space-3);
  background: transparent; border: 0; border-radius: var(--radius-xs);
  font-size: var(--text-sm); color: var(--color-text-secondary);
  transition: background var(--motion-fast), color var(--motion-fast);
}
.tab:hover { color: var(--color-text-primary); background: var(--color-surface-overlay); }
.tab[aria-selected="true"] { background: var(--color-accent); color: var(--color-text-inverse); font-weight: 700; }

/* select */
.axis-controls { display: flex; gap: var(--space-2); }
.select-wrap { display: inline-flex; align-items: center; gap: var(--space-1); }
.select-label { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-text-muted); }
.select {
  min-height: 36px; padding: 0 var(--space-6) 0 var(--space-2);
  background: var(--color-surface-inset) var(--select-arrow) no-repeat right var(--space-2) center;
  border: 1px solid var(--color-border-strong); border-radius: var(--radius-xs);
  font-size: var(--text-sm); color: var(--color-text-primary);
  -webkit-appearance: none; appearance: none;
  max-width: 150px;
}
.select:hover { border-color: var(--color-accent); }

/* --- 14. Performance grid --- */
.perf-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-4); }
.panel-wide { grid-column: 1 / -1; }
@media (max-width: 767px) { .perf-grid { grid-template-columns: minmax(0, 1fr); } }

/* --- 15. Pipeline steps --- */
.steps {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-4);
  counter-reset: step;
}
.step {
  position: relative;
  padding: var(--space-5);
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  transition: border-color var(--motion-base), transform var(--motion-base);
}
.step:hover { border-color: var(--color-accent); transform: translateY(-3px); }
.step-num {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px;
  font-family: var(--font-mono); font-weight: 700; font-size: var(--text-sm);
  background: var(--color-accent); color: var(--color-text-inverse);
  box-shadow: var(--shadow-1);
  margin-bottom: var(--space-3);
}
.step-title { font-size: var(--text-lg); font-weight: 700; margin-bottom: var(--space-2); }
.step-copy { font-size: var(--text-sm); color: var(--color-text-secondary); margin-bottom: var(--space-3); }
.step-code { display: block; font-size: var(--text-xs); color: var(--color-accent); border-left: 2px solid var(--color-accent); padding-left: var(--space-2); max-width: 100%; overflow-wrap: anywhere; }
@media (max-width: 1023px) { .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 767px) { .steps { grid-template-columns: minmax(0, 1fr); } }

/* --- 16. API cards --- */
.api-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-4); }
@media (max-width: 1023px) { .api-grid { grid-template-columns: minmax(0, 1fr); } }
.api-card { display: flex; flex-direction: column; gap: var(--space-3); }
.api-head { display: flex; align-items: center; gap: var(--space-2); flex-wrap: wrap; }
.method {
  font-family: var(--font-mono); font-size: var(--text-xs); font-weight: 700;
  padding: 3px var(--space-2); border-radius: var(--radius-xs);
  letter-spacing: 0.06em;
}
.method-post { background: var(--color-accent); color: var(--color-text-inverse); }
.method-get { background: var(--color-surface-overlay); color: var(--color-text-primary); border: 1px solid var(--color-border-strong); }
.api-path { font-size: var(--text-sm); color: var(--color-text-primary); }
.api-copy { font-size: var(--text-sm); color: var(--color-text-secondary); flex: 1; }
.code-wrap { position: relative; }
.code {
  background: var(--color-surface-inset);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  padding: var(--space-3);
  padding-right: 88px;
  font-size: var(--text-xs);
  line-height: 1.6;
  color: var(--color-text-secondary);
  overflow-x: auto;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.copy-btn { position: absolute; top: var(--space-1); right: var(--space-1); background: var(--color-surface-raised); }
.copy-btn.is-copied { color: var(--color-text-inverse); background: var(--color-accent); border-color: var(--color-accent); }

/* --- 17. Footer --- */
.footer { border-top: 1px solid var(--color-border); padding: var(--space-8) 0; }
.footer-inner { display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-4); }
.footer-brand { font-weight: 700; letter-spacing: 0.08em; }
.footer-version { font-family: var(--font-mono); font-weight: 400; font-size: var(--text-xs); color: var(--color-text-muted); margin-left: var(--space-2); }
.footer-copy { font-size: var(--text-sm); color: var(--color-text-secondary); margin-top: var(--space-1); }
.footer-copy strong { color: var(--color-text-primary); }
.footer-links { display: flex; flex-wrap: wrap; gap: var(--space-4); align-items: center; }
.footer-links a { font-size: var(--text-sm); display: inline-flex; align-items: center; min-height: var(--tap); }

/* --- 18. Toast & tooltip --- */
.toast {
  position: fixed; bottom: var(--space-4); left: 50%;
  transform: translateX(-50%);
  z-index: 90;
  max-width: calc(100vw - 2 * var(--gutter));
  padding: var(--space-2) var(--space-4);
  background: var(--color-surface-overlay);
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-xs);
  font-size: var(--text-sm);
  box-shadow: var(--shadow-1);
  animation: fade-up var(--motion-base) var(--ease-out);
}
.toast.is-error { border-color: var(--color-danger); }

.tooltip {
  position: fixed; z-index: 95;
  pointer-events: none;
  padding: var(--space-2) var(--space-3);
  background: var(--color-surface-overlay);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-xs);
  font-size: var(--text-xs);
  color: var(--color-text-primary);
  white-space: nowrap;
  box-shadow: var(--shadow-tooltip);
}
.tooltip strong { color: var(--color-accent); }
.tooltip .tt-row { display: flex; justify-content: space-between; gap: var(--space-3); }
.tooltip .tt-row + .tt-row { margin-top: 2px; }
.tooltip .tt-k { color: var(--color-text-muted); }

/* --- 19. Reveal on scroll --- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity var(--motion-slow) var(--ease-out), transform var(--motion-slow) var(--ease-out); }
.reveal.is-visible { opacity: 1; transform: none; }
.reveal:nth-child(2) { transition-delay: 60ms; }
.reveal:nth-child(3) { transition-delay: 120ms; }
.reveal:nth-child(4) { transition-delay: 180ms; }
.reveal:nth-child(5) { transition-delay: 240ms; }
.reveal:nth-child(6) { transition-delay: 300ms; }
.no-js .reveal { opacity: 1; transform: none; }

/* --- 20. Error page --- */
.error-main {
  min-height: 100vh; display: flex; flex-direction: column; align-items: flex-start; justify-content: center;
  padding: var(--space-8) var(--gutter); max-width: var(--container); margin-inline: auto;
}
.error-main .lede { margin-bottom: var(--space-6); }

/* --- 21. Responsive refinements --- */
@media (max-width: 767px) {
  :root { --nav-h: 56px; }
  .hero { padding: var(--space-10) 0 var(--space-8); }
  .section { padding: var(--space-10) 0; }
  .section-head { margin-bottom: var(--space-6); }
  .lede { font-size: var(--text-md); }
  .stat-strip { grid-template-columns: repeat(2, 1fr); }
  .stat:last-child:nth-child(odd) { grid-column: span 2; }
  .stat dd { font-size: var(--text-lg); }
  .table th, .table td { padding: var(--space-2) 6px; font-size: 13px; }
  .table { min-width: 0; }
  .panel { padding: var(--space-4); }
  .result-head { flex-direction: column-reverse; align-items: flex-start; }
  .ring { width: 100px; height: 100px; }
  .ring-value { font-size: 22px; }
  .ring-label { font-size: 8px; letter-spacing: 0.06em; }
  .prob-row { grid-template-columns: 84px 1fr 44px; }
  .panel-head { flex-direction: column; }
  .axis-controls { width: 100%; }
  .select-wrap { flex: 1; }
  .select { flex: 1; max-width: none; }
}
@media (max-width: 480px) {
  .hero-actions .btn { width: 100%; }
  .stat-strip { grid-template-columns: repeat(2, 1fr); }
  .preset-row .chip { flex: 1 1 calc(50% - var(--space-2)); justify-content: center; }
  .footer-inner { flex-direction: column; }
  .cm-cell { min-height: 56px; font-size: var(--text-md); }
  .cm-cell small { display: none; }
  .cm-head, .cm-row-head { font-size: 11px; letter-spacing: 0; text-transform: none; padding-inline: 2px; }
  .cm-row-head { padding-right: var(--space-1); }
  .tabs { width: 100%; }
  .tab { flex: 1; padding: 0 var(--space-2); font-size: var(--text-xs); }
}
@media (max-width: 360px) {
  .stat-strip { grid-template-columns: 1fr; }
  .stat:last-child:nth-child(odd) { grid-column: auto; }
  .brand-text { font-size: var(--text-sm); }
}
@media (min-width: 1440px) {
  :root { --container: 1280px; }
}

/* --- 22. Motion preferences --- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .noise { animation: none; }
  .reveal { opacity: 1; transform: none; }
  .glitch::before, .glitch::after { display: none; }
  .hero-title .w-in { transform: none; }
  .theme-toggle:hover .theme-icon { transform: none; }
  .cm-cell.is-pending, .chart .dots.is-pending .dot { opacity: 1; transform: none; }
  .cm-cell::after, .panel-result::before { display: none; }
}

@media (forced-colors: active) {
  .btn, .chip, .panel, .step { border: 1px solid ButtonText; }
  .prob-fill, .cm-cell { forced-color-adjust: none; }
}

@media print {
  .scanlines, .noise, .nav-toggle, .theme-toggle, .copy-btn, .toast, .tooltip { display: none !important; }
  body { background: #fff; color: #000; }
}