:root {
  color-scheme: dark light;
  --bg: #0d1117;
  --surface: #161b22;
  --surface-raised: #1b2129;
  --surface-soft: #11161d;
  --text: #f0f6fc;
  --muted: #8b949e;
  --muted-strong: #a8b3bf;
  --border: #30363d;
  --border-strong: #3d444d;
  --accent: #3fb950;
  --accent-soft: rgba(63, 185, 80, .12);
  --accent-border: rgba(63, 185, 80, .34);
  --blue: #58a6ff;
  --blue-soft: rgba(88, 166, 255, .11);
  --danger: #f85149;
  --danger-soft: rgba(248, 81, 73, .09);
  --warning: #d29922;
  --shadow-sm: 0 8px 24px rgba(0, 0, 0, .16);
  --shadow-lg: 0 24px 70px rgba(0, 0, 0, .28);
  --radius-sm: 9px;
  --radius: 14px;
  --radius-lg: 20px;
  --mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  line-height: 1.58;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: "";
  position: absolute;
  inset: 64px 0 auto;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border), transparent);
  pointer-events: none;
}

a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }
button, input, textarea { font: inherit; }
button { cursor: pointer; }
.shell { width: min(1180px, calc(100% - 32px)); margin: 0 auto; }

.skip-link {
  position: fixed;
  left: 14px;
  top: 14px;
  z-index: 200;
  padding: 9px 12px;
  border-radius: 9px;
  background: var(--text);
  color: var(--bg);
  transform: translateY(-180%);
  transition: transform .18s ease;
}
.skip-link:focus { transform: translateY(0); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  border-bottom: 1px solid color-mix(in srgb, var(--border) 85%, transparent);
  background: color-mix(in srgb, var(--canvas-2) 97%, black);
}
.header-inner {
  min-height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: var(--text);
  text-decoration: none;
}
.brand:hover { text-decoration: none; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  background: var(--surface);
  color: var(--accent);
  font: 700 13px var(--mono);
  box-shadow: inset 0 1px rgba(255,255,255,.03);
}
.brand-copy { display: grid; gap: 1px; line-height: 1.2; }
.brand-copy strong { font-size: 14px; }
.brand-copy small { color: var(--muted); font: 11px var(--mono); }
nav { display: flex; align-items: center; gap: 20px; font-size: 13px; }
nav a { color: var(--muted-strong); font-weight: 650; }
nav a:hover { color: var(--text); text-decoration: none; }

.hero {
  position: relative;
  max-width: 940px;
  padding: 88px 0 42px;
  animation: rise-in .45s cubic-bezier(.2,.8,.2,1) both;
}
.hero::after {
  content: "";
  display: block;
  width: min(640px, 78vw);
  height: 1px;
  margin-top: 34px;
  background: linear-gradient(90deg, var(--accent) 0 72px, var(--border) 72px, transparent 100%);
}
.eyebrow, .panel-kicker {
  margin: 0 0 9px;
  color: var(--accent);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .14em;
  text-transform: uppercase;
}
.eyebrow { display: flex; align-items: center; gap: 8px; }
.eyebrow-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }
h1, h2, h3, p { margin-top: 0; }
h1 {
  max-width: 900px;
  margin-bottom: 20px;
  font-size: clamp(42px, 6.2vw, 72px);
  line-height: .99;
  letter-spacing: -.052em;
  font-weight: 760;
}
.lede {
  max-width: 790px;
  margin-bottom: 24px;
  color: var(--muted-strong);
  font-size: clamp(17px, 2vw, 20px);
}
.trust-row { display: flex; flex-wrap: wrap; gap: 9px; }
.trust-row span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: color-mix(in srgb, var(--surface) 75%, transparent);
  color: var(--muted);
  font-size: 12px;
  font-weight: 650;
}
.trust-row i { width: 5px; height: 5px; border-radius: 50%; background: var(--accent); }
.hero-flow {
  display: flex;
  align-items: center;
  gap: 0;
  max-width: 680px;
  margin-top: 28px;
  color: var(--muted);
  font-size: 12px;
}
.hero-flow > div { display: flex; align-items: center; gap: 8px; }
.hero-flow > div:not(:last-child)::after { content: ""; width: 42px; height: 1px; margin: 0 12px; background: var(--border); }
.hero-flow b { color: var(--text); font: 700 11px var(--mono); }

.control-deck {
  position: relative;
  z-index: 30;
  display: grid;
  grid-template-columns: minmax(290px, 1.18fr) minmax(250px, .9fr) auto;
  gap: 0;
  align-items: stretch;
  margin-bottom: 14px;
  padding: 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  animation: rise-in .45s .06s cubic-bezier(.2,.8,.2,1) both;
}
.control-card {
  min-width: 0;
  padding: 9px 12px;
  border-right: 1px solid var(--border);
}
.control-card-primary { padding-left: 10px; }
.control-label {
  margin: 0 0 5px 2px;
  color: var(--muted);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: .1em;
  text-transform: uppercase;
}
.deck-actions { display: flex; align-items: center; gap: 8px; padding: 9px 6px 9px 12px; }

.native-select { display: none !important; }
.smart-select { position: relative; min-width: 0; }
.select-trigger {
  min-height: 48px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas: "value icon" "detail icon";
  align-items: center;
  column-gap: 14px;
  padding: 7px 11px;
  border: 1px solid transparent;
  border-radius: 11px;
  background: var(--surface-soft);
  outline: none;
  user-select: none;
  transition: border-color .16s ease, background .16s ease, transform .16s ease;
}
.select-trigger:hover { border-color: var(--border-strong); background: var(--surface-raised); }
.select-trigger:focus-visible, .select-trigger[aria-expanded="true"] {
  border-color: color-mix(in srgb, var(--blue) 65%, var(--border));
  box-shadow: 0 0 0 3px var(--blue-soft);
}
.select-value {
  grid-area: value;
  min-width: 0;
  overflow: hidden;
  color: var(--text);
  font-size: 13px;
  font-weight: 720;
  line-height: 1.3;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.select-detail {
  grid-area: detail;
  min-width: 0;
  overflow: hidden;
  margin-top: 2px;
  color: var(--muted);
  font-size: 11px;
  line-height: 1.35;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.select-chevron {
  grid-area: icon;
  width: 18px;
  height: 18px;
  display: grid;
  place-items: center;
  color: var(--muted);
  transition: transform .18s ease, color .18s ease;
}
.select-trigger[aria-expanded="true"] .select-chevron { transform: rotate(180deg); color: var(--text); }
.select-chevron::before { content: ""; width: 6px; height: 6px; border-right: 1.5px solid currentColor; border-bottom: 1.5px solid currentColor; transform: rotate(45deg) translate(-1px,-1px); }
.select-menu {
  position: absolute;
  top: calc(100% + 7px);
  left: 0;
  z-index: 120;
  width: max(100%, 320px);
  max-width: min(440px, calc(100vw - 32px));
  max-height: 340px;
  overflow: auto;
  padding: 6px;
  border: 1px solid var(--border-strong);
  border-radius: 14px;
  background: var(--surface-raised);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  transform: translateY(-5px) scale(.985);
  transform-origin: top left;
  pointer-events: none;
  transition: opacity .14s ease, transform .16s cubic-bezier(.2,.8,.2,1);
}
.smart-select.open .select-menu { opacity: 1; transform: translateY(0) scale(1); pointer-events: auto; }
.smart-select.open-up .select-menu { top: auto; bottom: calc(100% + 7px); transform-origin: bottom left; }
.select-group-label {
  padding: 9px 10px 5px;
  color: var(--muted);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: .1em;
  text-transform: uppercase;
}
.select-option {
  position: relative;
  display: grid;
  gap: 2px;
  padding: 9px 34px 9px 10px;
  border-radius: 9px;
  color: var(--muted-strong);
  outline: none;
  cursor: pointer;
}
.select-option:hover, .select-option.active { background: var(--blue-soft); color: var(--text); }
.select-option[aria-selected="true"] { color: var(--text); background: var(--accent-soft); }
.select-option[aria-selected="true"]::after {
  content: "";
  position: absolute;
  right: 13px;
  top: 50%;
  width: 8px;
  height: 4px;
  border-left: 1.7px solid var(--accent);
  border-bottom: 1.7px solid var(--accent);
  transform: translateY(-65%) rotate(-45deg);
}
.select-option-title { font-size: 13px; font-weight: 680; }
.select-option-detail { color: var(--muted); font-size: 11px; line-height: 1.35; }
.field .smart-select { width: 100%; }
.field .select-menu { width: 100%; }
.field .select-trigger { min-height: 42px; padding: 7px 10px; border-color: var(--border); }
.field .select-detail { display: none; }

.button, .copy-button, .text-button {
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface-raised);
  color: var(--text);
  font-weight: 700;
  transition: transform .14s ease, border-color .14s ease, background .14s ease, color .14s ease;
}
.button { min-height: 42px; padding: 8px 13px; white-space: nowrap; }
.button:hover, .copy-button:hover { border-color: var(--border-strong); background: color-mix(in srgb, var(--surface-raised) 82%, var(--text) 5%); }
.button:active, .copy-button:active { transform: translateY(1px); }
.button.primary { border-color: #2ea043; background: #238636; color: #fff; }
.button.primary:hover { background: #2ea043; }
.button.secondary span { color: var(--muted); }
.text-button { padding: 7px 10px; background: transparent; color: var(--blue); font-size: 12px; }
.text-button:hover { border-color: var(--blue); background: var(--blue-soft); }

.status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 32px;
  margin: 2px 0 18px;
  padding: 5px 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface-soft);
  color: var(--muted);
  font-size: 12px;
  transition: border-color .18s ease, color .18s ease, background .18s ease;
}
.status-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--muted); }
.status.loading .status-dot { background: var(--blue); animation: pulse-dot 1.25s ease-in-out infinite; }
.status.ready { border-color: var(--accent-border); background: var(--accent-soft); color: color-mix(in srgb, var(--text) 84%, var(--accent)); }
.status.ready .status-dot { background: var(--accent); }
.status.error { border-color: rgba(248,81,73,.35); background: var(--danger-soft); color: #ff7b72; }
.status.error .status-dot { background: var(--danger); }

.workspace {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(360px, .92fr);
  gap: 20px;
  align-items: start;
  animation: rise-in .45s .11s cubic-bezier(.2,.8,.2,1) both;
}
.panel {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
}
.editor-panel { overflow: visible; }
.preview-panel { overflow: hidden; }
.panel-heading {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  padding: 20px 21px 18px;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--surface) 82%, var(--surface-soft));
}
.panel-heading h2 { margin: 0 0 3px; font-size: 20px; line-height: 1.2; }
.panel-caption { margin: 0; color: var(--muted); font-size: 12px; }
.editor-panel form { display: grid; gap: 15px; padding: 18px; }
.root-section, .nested-section {
  min-width: 0;
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 15px;
  border: 1px solid var(--border);
  border-radius: 13px;
  background: var(--surface-soft);
  transition: border-color .16s ease, background .16s ease;
}
.root-section:hover { border-color: var(--border-strong); }
.root-section > legend {
  padding: 0 8px;
  color: var(--text);
  font-size: 14px;
  font-weight: 800;
}
.root-section.section-product { border-left: 2px solid var(--accent); }
.root-section.section-identity { border-left: 2px solid var(--blue); }
.root-section.section-instructions { border-left: 2px solid var(--muted); }
.nested-section { background: color-mix(in srgb, var(--surface-raised) 42%, transparent); }
.nested-section > legend { padding: 0 6px; color: var(--muted-strong); font-size: 11px; font-weight: 760; letter-spacing: .03em; }
.section-note { margin: -2px 0 1px; color: var(--muted); font-size: 11px; }
.field { display: grid; gap: 6px; min-width: 0; }
.field > label { color: var(--text); font-size: 12px; font-weight: 720; }
.field-help { margin: -1px 0 1px; color: var(--muted); font-size: 11px; line-height: 1.45; }
input, textarea {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg);
  color: var(--text);
  outline: none;
  transition: border-color .16s ease, box-shadow .16s ease, background .16s ease;
}
input { min-height: 42px; padding: 9px 11px; }
textarea { min-height: 88px; padding: 10px 11px; resize: vertical; line-height: 1.5; }
input:hover, textarea:hover { border-color: var(--border-strong); }
input:focus, textarea:focus { border-color: var(--blue); box-shadow: 0 0 0 3px var(--blue-soft); background: var(--surface-soft); }

.validation-summary {
  margin: 18px 18px 0;
  padding: 11px 13px;
  border: 1px solid var(--border);
  border-radius: 11px;
  color: var(--muted-strong);
  font-size: 12px;
  line-height: 1.5;
}
.validation-summary:empty { display: none; }
.validation-summary.valid { border-color: var(--accent-border); background: var(--accent-soft); color: color-mix(in srgb, var(--text) 88%, var(--accent)); }
.validation-summary.invalid { border-color: rgba(248,81,73,.35); background: var(--danger-soft); color: #ff9b95; }
.validation-summary > div + div { margin-top: 5px; }

.json-details { margin: 0 18px 18px; padding-top: 15px; border-top: 1px solid var(--border); }
.json-details summary {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  color: var(--text);
  cursor: pointer;
  font-size: 12px;
  font-weight: 750;
}
.json-details summary::marker { color: var(--muted); }
.json-details summary small { color: var(--muted); font-weight: 500; }
.json-details p { margin: 10px 0; color: var(--muted); font-size: 11px; }
.json-details textarea { min-height: 360px; font: 12px/1.55 var(--mono); }
.json-actions { display: flex; gap: 8px; margin-top: 9px; }

.preview-panel { position: sticky; top: 84px; }
.character-summary {
  max-width: 180px;
  color: var(--muted);
  font: 10px/1.45 var(--mono);
  text-align: right;
}
.output-stack { padding: 12px; display: grid; gap: 10px; }
.output-card {
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface-soft);
  transition: border-color .18s ease, transform .18s ease, background .18s ease;
}
.output-card:hover { border-color: var(--border-strong); }
.output-card.is-updated { animation: output-refresh .36s ease; }
.output-heading {
  min-height: 45px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 8px 10px 8px 12px;
  border-bottom: 1px solid var(--border);
}
.output-heading > div { display: flex; align-items: center; gap: 9px; min-width: 0; }
.output-index { color: var(--muted); font: 10px var(--mono); }
.output-heading h3 { margin: 0; font-size: 12px; font-weight: 750; }
.copy-button { padding: 5px 8px; background: transparent; color: var(--muted-strong); font-size: 10px; }
.copy-button.copied { border-color: var(--accent-border); background: var(--accent-soft); color: var(--accent); }
pre {
  min-height: 62px;
  max-height: 260px;
  margin: 0;
  padding: 12px;
  overflow: auto;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  color: #c9d1d9;
  font: 12px/1.62 var(--mono);
}
pre:empty::before { content: "No content yet."; color: var(--muted); }

.explanation {
  position: relative;
  max-width: 820px;
  padding: 66px 0 78px;
}
.explanation-rule { width: 72px; height: 2px; margin-bottom: 22px; background: var(--accent); }
.explanation h2 { margin-bottom: 12px; font-size: clamp(26px, 3vw, 34px); letter-spacing: -.025em; }
.explanation p { color: var(--muted-strong); }
.footer-inner { display: flex; justify-content: space-between; gap: 24px; }
footer { padding: 24px 0 40px; border-top: 1px solid var(--border); color: var(--muted); font-size: 11px; }
footer p { margin: 0; }

@keyframes rise-in { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
@keyframes pulse-dot { 0%,100% { opacity: .45; transform: scale(.85); } 50% { opacity: 1; transform: scale(1); } }
@keyframes output-refresh { 0% { background: var(--blue-soft); } 100% { background: var(--surface-soft); } }

@media (max-width: 960px) {
  .control-deck { grid-template-columns: 1fr 1fr; }
  .control-card:nth-child(2) { border-right: 0; }
  .deck-actions { grid-column: 1 / -1; justify-content: flex-end; border-top: 1px solid var(--border); }
  .workspace { grid-template-columns: 1fr; }
  .preview-panel { position: static; }
  .footer-inner { flex-direction: column; gap: 4px; }
}

@media (max-width: 680px) {
  .shell { width: min(100% - 22px, 1180px); }
  .header-inner { min-height: 58px; gap: 12px; }
  .brand-copy small { display: none; }
  nav { gap: 12px; font-size: 12px; }
  nav a:nth-child(3) { display: none; }
  .hero { padding: 58px 0 30px; }
  h1 { font-size: clamp(40px, 12vw, 56px); }
  .lede { font-size: 16px; }
  .hero-flow { align-items: flex-start; flex-direction: column; gap: 7px; }
  .hero-flow > div:not(:last-child)::after { display: none; }
  .control-deck { grid-template-columns: 1fr; padding: 7px; }
  .control-card { border-right: 0; border-bottom: 1px solid var(--border); padding: 10px 8px; }
  .deck-actions { grid-column: auto; padding: 12px 8px 7px; border-top: 0; justify-content: stretch; }
  .deck-actions .button { flex: 1; }
  .select-menu {
    width: 100%;
    max-width: 100%;
    max-height: min(52vh, 340px);
    border-radius: 14px;
  }
  .select-option { padding-top: 11px; padding-bottom: 11px; }
  .panel-heading { padding: 18px 16px 16px; }
  .editor-panel form { padding: 14px; }
  .validation-summary { margin: 14px 14px 0; }
  .json-details { margin: 0 14px 14px; }
  .output-stack { padding: 8px; }
  .character-summary { display: none; }
  .explanation { padding: 52px 0 64px; }
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f6f8fa;
    --surface: #ffffff;
    --surface-raised: #ffffff;
    --surface-soft: #f6f8fa;
    --text: #1f2328;
    --muted: #636c76;
    --muted-strong: #59636e;
    --border: #d0d7de;
    --border-strong: #afb8c1;
    --accent: #1a7f37;
    --accent-soft: rgba(26,127,55,.08);
    --accent-border: rgba(26,127,55,.25);
    --blue: #0969da;
    --blue-soft: rgba(9,105,218,.08);
    --danger: #cf222e;
    --danger-soft: rgba(207,34,46,.07);
    --shadow-sm: 0 10px 30px rgba(31,35,40,.07);
    --shadow-lg: 0 20px 55px rgba(31,35,40,.16);
  }
  .site-header { background: rgba(255,255,255,.88); }
  pre { color: #24292f; }
  .button.primary { color: #fff; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    scroll-behavior: auto !important;
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
}