/* AI Function Nodes — one stylesheet, no external fonts, no CDN. */

:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --bg-soft: #f7f7fa;
  --bg-raised: #ffffff;
  --fg: #16161c;
  --fg-muted: #5f5f70;
  --fg-faint: #8a8a9c;
  --rule: #e6e6ee;
  --rule-strong: #d6d6e2;
  --accent: #6b46f5;
  --accent-soft: #f0ecff;
  --accent-fg: #ffffff;
  --render: #e8590c;
  --convert: #0b7285;
  --ai: #6b46f5;
  --ok: #0f8a4d;
  --err: #d32f2f;
  --radius: 12px;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", sans-serif;
  --shadow: 0 1px 2px rgba(20, 20, 40, 0.06), 0 8px 24px -12px rgba(20, 20, 40, 0.14);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0c0c11;
    --bg-soft: #121218;
    --bg-raised: #15151c;
    --fg: #e9e9f2;
    --fg-muted: #a0a0b4;
    --fg-faint: #74748a;
    --rule: #24242f;
    --rule-strong: #32323f;
    --accent: #a48cff;
    --accent-soft: #1d1930;
    --accent-fg: #12101f;
    --render: #ff9f5a;
    --convert: #4ecdc4;
    --ai: #a48cff;
    --ok: #4ade80;
    --err: #ff7b7b;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 12px 32px -16px rgba(0, 0, 0, 0.8);
  }
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--sans);
  background: var(--bg);
  color: var(--fg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  font-size: 16px;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

code,
pre,
kbd {
  font-family: var(--mono);
  font-size: 0.875em;
}

.wrap {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 1.5rem;
}
.wrap-narrow {
  max-width: 820px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ---------------------------------------------------------------- header */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--rule);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  height: 60px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 640;
  letter-spacing: -0.01em;
  color: var(--fg);
}
.brand:hover {
  text-decoration: none;
}
.brand-mark {
  width: 26px;
  height: 26px;
  flex: none;
}
.nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 1.25rem;
  font-size: 0.9rem;
}
.nav a {
  color: var(--fg-muted);
}
.nav a:hover {
  color: var(--fg);
  text-decoration: none;
}
@media (max-width: 640px) {
  .nav .hide-sm {
    display: none;
  }
}

/* ------------------------------------------------------------------ hero */

.hero {
  padding: 5rem 0 3rem;
  border-bottom: 1px solid var(--rule);
  background: radial-gradient(1200px 400px at 50% -180px, var(--accent-soft), transparent 70%);
}
.hero h1 {
  font-size: clamp(2rem, 5vw, 3.1rem);
  line-height: 1.08;
  letter-spacing: -0.03em;
  margin: 0 0 1rem;
  font-weight: 680;
  max-width: 20ch;
}
.hero p.lede {
  font-size: clamp(1.02rem, 2vw, 1.2rem);
  color: var(--fg-muted);
  max-width: 62ch;
  margin: 0 0 1.75rem;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid color-mix(in srgb, var(--accent) 25%, transparent);
  padding: 0.28rem 0.7rem;
  border-radius: 999px;
  margin-bottom: 1.25rem;
}
.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.1rem;
  border-radius: 9px;
  border: 1px solid var(--rule-strong);
  background: var(--bg-raised);
  color: var(--fg);
  font-size: 0.92rem;
  font-weight: 550;
  cursor: pointer;
  transition: transform 0.12s ease, border-color 0.12s ease, background 0.12s ease;
}
.btn:hover {
  text-decoration: none;
  border-color: var(--accent);
  transform: translateY(-1px);
}
.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-fg);
}
.btn-primary:hover {
  filter: brightness(1.07);
}
.btn[disabled] {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
}

/* ----------------------------------------------------------------- cards */

section.block {
  padding: 3.5rem 0;
}
section.block + section.block {
  border-top: 1px solid var(--rule);
}
h2.section-title {
  font-size: 1.45rem;
  letter-spacing: -0.02em;
  margin: 0 0 0.4rem;
}
p.section-sub {
  color: var(--fg-muted);
  margin: 0 0 1.75rem;
  max-width: 65ch;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}

.card {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  padding: 1.15rem 1.25rem 1.25rem;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--bg-raised);
  color: var(--fg);
  transition: transform 0.14s ease, border-color 0.14s ease, box-shadow 0.14s ease;
}
a.card:hover {
  text-decoration: none;
  transform: translateY(-2px);
  border-color: var(--rule-strong);
  box-shadow: var(--shadow);
}
.card-head {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}
.card-icon {
  width: 22px;
  height: 22px;
  flex: none;
  stroke-width: 1.6;
  fill: none;
  stroke: currentColor;
}
.card h3 {
  margin: 0;
  font-size: 1rem;
  font-weight: 620;
  letter-spacing: -0.01em;
}
.card p {
  margin: 0;
  color: var(--fg-muted);
  font-size: 0.9rem;
  line-height: 1.55;
}
.card-foot {
  margin-top: auto;
  padding-top: 0.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  align-items: center;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 0.16rem 0.5rem;
  border-radius: 999px;
  border: 1px solid var(--rule-strong);
  color: var(--fg-faint);
  white-space: nowrap;
}
.chip-render {
  color: var(--render);
  border-color: color-mix(in srgb, var(--render) 40%, transparent);
}
.chip-convert {
  color: var(--convert);
  border-color: color-mix(in srgb, var(--convert) 40%, transparent);
}
.chip-ai {
  color: var(--ai);
  border-color: color-mix(in srgb, var(--ai) 40%, transparent);
}
.chip-free {
  color: var(--ok);
  border-color: color-mix(in srgb, var(--ok) 40%, transparent);
}

/* ------------------------------------------------------------- code bits */

pre.code {
  margin: 0;
  padding: 1rem 1.1rem;
  background: var(--bg-soft);
  border: 1px solid var(--rule);
  border-radius: 10px;
  overflow-x: auto;
  font-size: 0.82rem;
  line-height: 1.6;
  tab-size: 2;
}
pre.code code {
  font-size: inherit;
}
.code-wrap {
  position: relative;
}
.copy-btn {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  padding: 0.25rem 0.55rem;
  font-size: 0.72rem;
  border-radius: 6px;
  border: 1px solid var(--rule-strong);
  background: var(--bg-raised);
  color: var(--fg-muted);
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.12s ease;
}
.code-wrap:hover .copy-btn,
.copy-btn:focus {
  opacity: 1;
}
.copy-btn.copied {
  color: var(--ok);
  border-color: var(--ok);
  opacity: 1;
}

.tabs {
  display: flex;
  gap: 0.25rem;
  border-bottom: 1px solid var(--rule);
  margin-bottom: 0.85rem;
  overflow-x: auto;
}
.tab {
  padding: 0.45rem 0.8rem;
  font-size: 0.84rem;
  color: var(--fg-muted);
  background: none;
  border: 0;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  white-space: nowrap;
  font-family: inherit;
}
.tab[aria-selected="true"] {
  color: var(--fg);
  border-bottom-color: var(--accent);
  font-weight: 570;
}

/* ------------------------------------------------------------ tool page */

.tool-header {
  padding: 2.5rem 0 1.75rem;
  border-bottom: 1px solid var(--rule);
}
.breadcrumb {
  font-size: 0.82rem;
  color: var(--fg-faint);
  margin-bottom: 0.75rem;
}
.tool-header h1 {
  font-size: clamp(1.7rem, 4vw, 2.35rem);
  letter-spacing: -0.025em;
  margin: 0 0 0.5rem;
  font-weight: 660;
}
.tool-header .lede {
  color: var(--fg-muted);
  font-size: 1.05rem;
  margin: 0 0 1rem;
  max-width: 70ch;
}
.endpoint {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--mono);
  font-size: 0.8rem;
  padding: 0.35rem 0.7rem;
  border: 1px solid var(--rule);
  border-radius: 8px;
  background: var(--bg-soft);
  color: var(--fg-muted);
}
.endpoint .verb {
  color: var(--accent);
  font-weight: 700;
}

.tool-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 1.5rem;
  padding: 1.75rem 0 3rem;
  align-items: start;
}
@media (max-width: 940px) {
  .tool-layout {
    grid-template-columns: minmax(0, 1fr);
  }
}

.panel {
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--bg-raised);
  overflow: hidden;
}
.panel-head {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.75rem 1.1rem;
  border-bottom: 1px solid var(--rule);
  background: var(--bg-soft);
}
.panel-head h2 {
  margin: 0;
  font-size: 0.82rem;
  font-weight: 640;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--fg-muted);
}
.panel-head .spacer {
  margin-left: auto;
}
.panel-body {
  padding: 1.1rem;
}

/* ------------------------------------------------------------------ form */

.field {
  margin-bottom: 1rem;
}
.field:last-child {
  margin-bottom: 0;
}
.field > label,
.field > .label {
  display: block;
  font-size: 0.84rem;
  font-weight: 580;
  margin-bottom: 0.3rem;
}
.field .hint {
  display: block;
  font-size: 0.78rem;
  color: var(--fg-faint);
  margin-top: 0.3rem;
  line-height: 1.5;
}
.field .name {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--fg-faint);
  font-weight: 400;
  margin-left: 0.35rem;
}

input[type="text"],
input[type="url"],
input[type="number"],
select,
textarea {
  width: 100%;
  padding: 0.5rem 0.65rem;
  font-family: inherit;
  font-size: 0.9rem;
  color: var(--fg);
  background: var(--bg);
  border: 1px solid var(--rule-strong);
  border-radius: 8px;
  transition: border-color 0.12s ease, box-shadow 0.12s ease;
}
textarea {
  font-family: var(--mono);
  font-size: 0.82rem;
  line-height: 1.55;
  resize: vertical;
  min-height: 4.5rem;
}
input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);
}
input[type="file"] {
  font-size: 0.85rem;
  color: var(--fg-muted);
}

.switch-row {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
}
.switch-row input[type="checkbox"] {
  margin-top: 0.28rem;
  width: 1rem;
  height: 1rem;
  accent-color: var(--accent);
  flex: none;
}
.switch-row .label {
  margin: 0;
}

.checks {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 0.9rem;
}
.checks label {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.85rem;
  font-family: var(--mono);
  color: var(--fg-muted);
}
.checks input {
  accent-color: var(--accent);
}

details.advanced {
  margin-top: 1rem;
  border-top: 1px dashed var(--rule-strong);
  padding-top: 0.9rem;
}
details.advanced > summary {
  cursor: pointer;
  font-size: 0.84rem;
  font-weight: 570;
  color: var(--fg-muted);
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
details.advanced > summary::-webkit-details-marker {
  display: none;
}
details.advanced > summary::before {
  content: "▸";
  transition: transform 0.15s ease;
  display: inline-block;
}
details.advanced[open] > summary::before {
  transform: rotate(90deg);
}
details.advanced > .advanced-body {
  padding-top: 1rem;
}

.run-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-top: 1.25rem;
  flex-wrap: wrap;
}
.example-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1rem;
}
.example-btn {
  font-size: 0.78rem;
  padding: 0.28rem 0.6rem;
  border-radius: 999px;
  border: 1px dashed var(--rule-strong);
  background: none;
  color: var(--fg-muted);
  cursor: pointer;
  font-family: inherit;
}
.example-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  border-style: solid;
}

.status {
  font-size: 0.83rem;
  color: var(--fg-muted);
}
.status.err {
  color: var(--err);
}
.status.ok {
  color: var(--ok);
}

.spinner {
  width: 14px;
  height: 14px;
  border: 2px solid color-mix(in srgb, var(--accent) 30%, transparent);
  border-top-color: var(--accent);
  border-radius: 50%;
  display: inline-block;
  animation: spin 0.7s linear infinite;
  vertical-align: -2px;
  margin-right: 0.4rem;
}
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* ---------------------------------------------------------------- result */

#result-empty {
  color: var(--fg-faint);
  font-size: 0.88rem;
  text-align: center;
  padding: 2.5rem 1rem;
}
.result-out {
  max-height: 32rem;
  overflow: auto;
  border-radius: 8px;
}
.result-out pre.code {
  border: 0;
  background: var(--bg-soft);
}
.result-frame {
  width: 100%;
  height: 30rem;
  border: 1px solid var(--rule);
  border-radius: 8px;
  background: #fff;
}
.result-img {
  max-width: 100%;
  border: 1px solid var(--rule);
  border-radius: 8px;
  display: block;
}
.result-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 0.75rem;
}
.badge {
  font-family: var(--mono);
  font-size: 0.72rem;
  padding: 0.15rem 0.45rem;
  border-radius: 5px;
  background: var(--bg-soft);
  border: 1px solid var(--rule);
  color: var(--fg-muted);
}

.md-preview {
  font-size: 0.9rem;
  line-height: 1.7;
  padding: 0.25rem 0.25rem 0.5rem;
}
.md-preview h1,
.md-preview h2,
.md-preview h3 {
  font-size: 1.05rem;
  margin: 1.1rem 0 0.4rem;
}
.md-preview pre {
  background: var(--bg-soft);
  padding: 0.75rem;
  border-radius: 8px;
  overflow-x: auto;
}
.md-preview table {
  border-collapse: collapse;
  width: 100%;
}
.md-preview th,
.md-preview td {
  border: 1px solid var(--rule);
  padding: 0.35rem 0.55rem;
  text-align: left;
}

/* ------------------------------------------------------------------ prose */

.prose {
  max-width: 74ch;
}
.prose h2 {
  font-size: 1.35rem;
  letter-spacing: -0.02em;
  margin: 2.5rem 0 0.75rem;
  scroll-margin-top: 5rem;
}
.prose h3 {
  font-size: 1.05rem;
  margin: 1.75rem 0 0.5rem;
  scroll-margin-top: 5rem;
}
.prose p {
  margin: 0.85rem 0;
  color: var(--fg-muted);
}
.prose li {
  color: var(--fg-muted);
  margin: 0.3rem 0;
}
.prose strong {
  color: var(--fg);
}
.prose code {
  background: var(--bg-soft);
  border: 1px solid var(--rule);
  padding: 0.1em 0.35em;
  border-radius: 5px;
}
.prose pre.code code {
  background: none;
  border: 0;
  padding: 0;
}
.prose table {
  border-collapse: collapse;
  width: 100%;
  margin: 1.25rem 0;
  font-size: 0.9rem;
}
.prose th,
.prose td {
  border: 1px solid var(--rule);
  padding: 0.45rem 0.7rem;
  text-align: left;
  vertical-align: top;
}
.prose th {
  background: var(--bg-soft);
  font-weight: 600;
}
.prose blockquote {
  margin: 1.25rem 0;
  padding: 0.1rem 0 0.1rem 1rem;
  border-left: 3px solid var(--accent);
  color: var(--fg-muted);
}

table.params {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.86rem;
}
table.params th,
table.params td {
  border-bottom: 1px solid var(--rule);
  padding: 0.5rem 0.6rem;
  text-align: left;
  vertical-align: top;
}
table.params th {
  font-size: 0.74rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--fg-faint);
  border-bottom-color: var(--rule-strong);
}
table.params td.pname {
  font-family: var(--mono);
  font-size: 0.8rem;
  white-space: nowrap;
  color: var(--fg);
}
table.params td.ptype {
  font-family: var(--mono);
  font-size: 0.76rem;
  color: var(--fg-faint);
  white-space: nowrap;
}
table.params td.pdesc {
  color: var(--fg-muted);
}
.req {
  color: var(--err);
  font-weight: 700;
}

/* ------------------------------------------------------------------ misc */

.callout {
  border: 1px solid var(--rule);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 0.9rem 1.1rem;
  background: var(--bg-soft);
  font-size: 0.9rem;
  color: var(--fg-muted);
  margin: 1.25rem 0;
}
.callout strong {
  color: var(--fg);
}

.two-col {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.25rem;
}

.site-footer {
  border-top: 1px solid var(--rule);
  padding: 2.5rem 0;
  color: var(--fg-faint);
  font-size: 0.85rem;
}
.site-footer .wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2rem;
  align-items: center;
}
.site-footer a {
  color: var(--fg-muted);
}
.site-footer .spacer {
  margin-left: auto;
}

.toc-side {
  position: sticky;
  top: 5rem;
  font-size: 0.85rem;
}
.toc-side a {
  display: block;
  padding: 0.15rem 0;
  color: var(--fg-muted);
}
.toc-side a:hover {
  color: var(--accent);
  text-decoration: none;
}

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