/* JsonYard — Soft IDE light (unique visual system; not a recolor of sisters) */
:root {
  --bg: #f5f6f8;
  --bg-muted: #eef0f4;
  --panel: #ffffff;
  --line: #e2e5eb;
  --line-strong: #d0d5dd;
  --accent: #5b6cff;
  --accent-soft: #eef0ff;
  --accent-text: #3d4ad9;
  --danger: #c23b3b;
  --danger-soft: #fdecec;
  --ok: #1a7f4b;
  --ok-soft: #e6f6ed;
  --warn: #b45309;
  --text: #1c2333;
  --muted: #667085;
  --syntax-key: #4a5fd9;
  --syntax-str: #a15c2a;
  --syntax-num: #0f766e;
  --syntax-bool: #7c3aed;
  --radius: 6px;
  --radius-sm: 4px;
  --page-max: 72rem;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --text-base: 1rem;
  --text-sm: 0.875rem;
  --text-xs: 0.8125rem;
  --editor-size: 0.9375rem;
  --shadow-soft: 0 1px 2px rgba(28, 35, 51, 0.04), 0 0 0 1px var(--line);
  --safe-b: env(safe-area-inset-bottom, 0px);
  --safe-t: env(safe-area-inset-top, 0px);
}
*, *::before, *::after { box-sizing: border-box; }
html { height: 100%; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  min-height: 100%;
  font-family: var(--font);
  font-size: var(--text-base);
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  padding-bottom: var(--safe-b);
}
html[lang^="zh"] body { line-height: 1.65; }
img, svg { display: block; max-width: 100%; }
a { color: var(--accent-text); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--accent); }
code, kbd {
  font-family: var(--mono);
  font-size: 0.9em;
  background: var(--bg-muted);
  padding: 0.1em 0.35em;
  border-radius: 3px;
}
.skip-link {
  position: absolute; left: -999px; top: 0; z-index: 100;
  background: var(--accent); color: #fff; padding: 0.5rem 0.75rem;
}
.skip-link:focus { left: 0.5rem; top: 0.5rem; }

/* —— Shell: IDE workspace, not paper column / rail / cards / darkroom —— */
.ide-shell {
  max-width: var(--page-max);
  margin: 0 auto;
  padding: calc(0.75rem + var(--safe-t)) 1rem 2.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  min-height: 100vh;
}

/* Topbar — flat IDE chrome */
.mast {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 0.75rem;
  padding: 0.35rem 0 0.65rem;
  border-bottom: 1px solid var(--line);
}
.brand a {
  display: flex; align-items: center; gap: 0.55rem;
  text-decoration: none; color: inherit;
}
.brand-mark {
  display: block;
  width: 28px;
  height: 28px;
  flex: 0 0 auto;
  border-radius: var(--radius-sm);
}
.brand-name { font-weight: 650; font-size: 1.05rem; letter-spacing: -0.02em; white-space: nowrap; }
.brand small { display: block; color: var(--muted); font-size: var(--text-xs); font-weight: 500; }
.top-actions {
  display: flex; flex-wrap: wrap; align-items: center; gap: 0.25rem;
}
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 0.35rem;
  font: inherit; font-size: var(--text-sm); font-weight: 550;
  line-height: 1.2; padding: 0.45rem 0.7rem; min-height: 40px;
  border-radius: var(--radius-sm); border: 1px solid transparent;
  background: transparent; color: var(--text); cursor: pointer;
  text-decoration: none; white-space: nowrap;
}
.btn:hover { background: var(--bg-muted); }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.btn-ghost { color: var(--muted); }
.btn-ghost:hover { color: var(--text); }
.btn-primary {
  background: var(--accent); color: #fff; border-color: var(--accent);
}
.btn-primary:hover { filter: brightness(1.05); background: var(--accent); color: #fff; }
.btn-secondary {
  background: var(--panel); border-color: var(--line-strong); color: var(--text);
}
.btn-secondary:hover { border-color: var(--accent); color: var(--accent-text); background: var(--accent-soft); }
.lang-switch { display: inline-flex; gap: 0; border: 1px solid var(--line); border-radius: var(--radius-sm); overflow: hidden; }
.lang-btn { min-width: 44px; border-radius: 0; min-height: 40px; }
.lang-btn[aria-pressed="true"] { background: var(--accent-soft); color: var(--accent-text); font-weight: 650; }

/* Header XOR — critical: beat .btn later in cascade */
.nav-toggle,
.btn.nav-toggle { display: none; }
.nav-guides {
  display: flex; flex-wrap: wrap; align-items: center; gap: 0.15rem;
}
.nav-guides a {
  font-size: var(--text-sm); color: var(--muted); text-decoration: none;
  padding: 0.4rem 0.55rem; border-radius: var(--radius-sm); min-height: 40px;
  display: inline-flex; align-items: center;
}
.nav-guides a:hover { color: var(--accent-text); background: var(--accent-soft); }
@media (min-width: 900px) {
  .nav-toggle,
  .btn.nav-toggle { display: none !important; }
  .nav-guides { display: flex !important; position: static; }
}
@media (max-width: 899px) {
  .nav-toggle,
  .btn.nav-toggle { display: inline-flex !important; }
  .nav-guides {
    display: none; position: absolute; right: 1rem; top: 3.5rem; z-index: 40;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
    box-shadow: 0 8px 24px rgba(28, 35, 51, 0.08); padding: 0.35rem; min-width: 11rem;
  }
  .nav-guides.is-open { display: flex; }
  .nav-guides a { padding: 0.55rem 0.7rem; }
  .mast { position: relative; }
}
.top-converter-short { display: none; }
@media (max-width: 430px) {
  .top-converter-full { display: none; }
  .top-converter-short { display: inline; }
}

/* Quiet title — keywords first, not a marketing hero */
.title-row {
  display: flex; flex-wrap: wrap; align-items: flex-end; justify-content: space-between;
  gap: 0.5rem 1rem;
}
.title-row h1 {
  margin: 0; font-size: clamp(1.35rem, 2.2vw, 1.65rem); font-weight: 650;
  letter-spacing: -0.025em; line-height: 1.25;
}
.title-row .lead {
  margin: 0.25rem 0 0; color: var(--muted); font-size: var(--text-base); max-width: 42rem;
}
.session-chip {
  font-family: var(--mono); font-size: var(--text-xs); color: var(--muted);
  background: var(--panel); border: 1px solid var(--line); border-radius: 999px;
  padding: 0.35rem 0.7rem; white-space: nowrap;
}
.trust-line {
  margin: 0; font-size: var(--text-sm); color: var(--muted);
}
.trust-line strong { color: var(--ok); font-weight: 650; }

/* Mode tab bar — IDE language */
.ide-toolbar {
  display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem;
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 0.35rem 0.45rem; box-shadow: var(--shadow-soft);
}
.mode-tabs {
  display: inline-flex; gap: 0.15rem; flex-wrap: wrap;
  background: var(--bg-muted); border-radius: var(--radius-sm); padding: 0.15rem;
}
.mode-tab {
  font: inherit; font-size: var(--text-sm); font-weight: 550;
  padding: 0.4rem 0.75rem; min-height: 36px; border: 0; border-radius: 3px;
  background: transparent; color: var(--muted); cursor: pointer;
}
.mode-tab[aria-selected="true"] {
  background: var(--panel); color: var(--text); box-shadow: 0 1px 2px rgba(28,35,51,0.06);
  font-weight: 650;
}
.mode-tab:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
.toolbar-actions {
  display: flex; flex-wrap: wrap; align-items: center; gap: 0.3rem; margin-left: auto;
}
.convert-opts {
  display: none; flex-wrap: wrap; align-items: center; gap: 0.35rem;
  width: 100%; padding: 0.25rem 0.15rem 0.1rem; border-top: 1px solid var(--line); margin-top: 0.25rem;
}
.convert-opts.is-on { display: flex; }
.convert-opts label {
  font-size: var(--text-sm); color: var(--muted); display: inline-flex; align-items: center; gap: 0.35rem;
}
.convert-opts select {
  font: inherit; font-size: var(--text-sm); padding: 0.35rem 0.5rem; min-height: 36px;
  border: 1px solid var(--line); border-radius: var(--radius-sm); background: var(--panel);
}

/* Dual-pane workbench — signature chrome */
.workbench {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
  box-shadow: var(--shadow-soft);
  min-height: 420px;
  flex: 1 1 auto;
}
.pane {
  display: flex; flex-direction: column; min-width: 0; min-height: 0;
  background: var(--panel);
}
.pane + .pane { border-left: 1px solid var(--line); }
.pane-head {
  display: flex; align-items: center; justify-content: space-between; gap: 0.5rem;
  padding: 0.4rem 0.65rem; background: var(--bg-muted);
  border-bottom: 1px solid var(--line); font-size: var(--text-sm); font-weight: 600;
  color: var(--muted); letter-spacing: 0.01em;
}
.pane-head .pane-label { text-transform: uppercase; font-size: var(--text-xs); letter-spacing: 0.06em; }
.pane-body {
  flex: 1; position: relative; min-height: 280px;
}
.editor,
.output {
  width: 100%; height: 100%; min-height: 280px; border: 0; resize: none;
  padding: 0.85rem 1rem; font-family: var(--mono); font-size: var(--editor-size);
  line-height: 1.55; color: var(--text); background: var(--panel);
  tab-size: 2; outline: none;
}
.output { background: #fafbfc; color: var(--text); }
.editor:focus { box-shadow: inset 0 0 0 2px var(--accent-soft); }
.editor::placeholder { color: #98a2b3; }
.hl-layer {
  display: none; /* lightweight: we use textarea; optional future overlay */
}
@media (max-width: 860px) {
  .workbench { grid-template-columns: 1fr; min-height: 0; }
  .pane + .pane { border-left: 0; border-top: 1px solid var(--line); }
  .pane-body, .editor, .output { min-height: 220px; }
}

/* Status bar — IDE footer */
.status-bar {
  display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem 1rem;
  padding: 0.35rem 0.75rem; background: var(--bg-muted);
  border: 1px solid var(--line); border-radius: var(--radius);
  font-family: var(--mono); font-size: var(--text-xs); color: var(--muted);
}
.status-bar .stat { display: inline-flex; align-items: center; gap: 0.35rem; }
.badge {
  display: inline-flex; align-items: center; gap: 0.25rem;
  padding: 0.15rem 0.45rem; border-radius: 3px; font-weight: 650;
}
.badge-ok { background: var(--ok-soft); color: var(--ok); }
.badge-err { background: var(--danger-soft); color: var(--danger); }
.badge-idle { background: var(--panel); color: var(--muted); border: 1px solid var(--line); }
.err-msg { color: var(--danger); max-width: 100%; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* Proof / SEO below workbench */
.proof {
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel);
  padding: 0.75rem 1rem;
}
.proof summary { cursor: pointer; font-weight: 600; font-size: var(--text-sm); color: var(--muted); }
.proof ol { margin: 0.5rem 0 0; padding-left: 1.2rem; font-size: var(--text-base); }
.seo-block, .faq {
  margin-top: 1.5rem; padding-top: 1.25rem; border-top: 1px solid var(--line);
}
.seo-block h2, .faq h2 {
  margin: 0 0 0.75rem; font-size: 1.25rem; letter-spacing: -0.02em;
}
.seo-copy p, .seo-copy li, .faq details p {
  font-size: var(--text-base); /* floor 16px — never text-sm */
  color: var(--text);
}
.faq details {
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel);
  padding: 0.65rem 0.85rem; margin-bottom: 0.5rem;
}
.faq summary { font-weight: 600; cursor: pointer; }
.guide-cards {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(14rem, 1fr)); gap: 0.65rem;
}
.guide-card {
  display: block; padding: 0.85rem; border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--panel); text-decoration: none; color: inherit;
}
.guide-card:hover { border-color: var(--accent); background: var(--accent-soft); }
.guide-card strong { display: block; margin-bottom: 0.25rem; }
.guide-card span { color: var(--muted); font-size: var(--text-sm); }

footer.site-foot {
  margin-top: 2rem; padding-top: 1.25rem; padding-bottom: 0.35rem; border-top: 1px solid var(--line);
  font-size: var(--text-sm); color: var(--muted); width: 100%;
}
footer.site-foot a { color: var(--muted); text-decoration: none; }
footer.site-foot a:hover { color: var(--accent-text); text-decoration: underline; }

/* Inner / legal pages */
.wrap { max-width: var(--page-max); margin: 0 auto; padding: 1rem 1rem 2.5rem; }
.topbar--compact { margin-bottom: 1.25rem; }
.legal-page h1 { font-size: 1.75rem; letter-spacing: -0.02em; margin: 0 0 0.35rem; }
.legal-page h2 { font-size: 1.2rem; margin: 1.5rem 0 0.5rem; }
.legal-page p, .legal-page li { font-size: var(--text-base); }
.legal-page .lead { color: var(--muted); }
.article-page { max-width: 44rem; }
.article-page h1 { font-size: clamp(1.5rem, 3vw, 1.85rem); letter-spacing: -0.02em; }
.article-page p, .article-page li { font-size: var(--text-base); }
.cta-box {
  margin: 1.5rem 0; padding: 1rem; border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--accent-soft);
}
.field { flex: 0 0 auto; } /* never flex-grow blank strips */

@media (max-width: 480px) {
  .ide-shell { padding-left: 0.75rem; padding-right: 0.75rem; }
  .toolbar-actions .btn span.hide-sm { display: none; }
}

/* Full-width multi-column footer (portfolio layout) */
.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem 1.5rem;
  width: 100%;
  align-items: start;
}
.footer-col { min-width: 0; }
.footer-label {
  margin: 0 0 0.45rem;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent, var(--accent-text, currentColor));
  opacity: 0.95;
}
.footer-copy { margin: 0 0 0.4rem; color: var(--muted); }
.footer-note { margin: 0; color: var(--muted); opacity: 0.85; max-width: 22rem; line-height: 1.45; }
.footer-links,
.cross-links {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.35rem;
  margin: 0;
}
.footer-links a,
.cross-links a { margin: 0; }
@media (min-width: 700px) {
  .footer-grid {
    grid-template-columns: minmax(12rem, 1.4fr) minmax(8rem, 0.9fr) minmax(9rem, 1fr);
    gap: 1.5rem 2rem;
  }
}

/* UX-OPT-2026-10-20 */
.limit-note {
  margin: 0.35rem 0 0;
  font-size: 0.8125rem;
  line-height: 1.35;
  color: var(--muted, #64748b);
  max-width: 36rem;
}
.limit-note strong { color: var(--ink, #0f172a); font-weight: 600; }
.ux-banner {
  display: none;
  margin: 0.75rem 0;
  padding: 0.65rem 0.9rem;
  border-radius: 10px;
  font-size: 0.875rem;
  line-height: 1.4;
  border: 1px solid transparent;
}
.ux-banner.is-on { display: block; }
.ux-banner.is-ok {
  background: color-mix(in srgb, #10b981 12%, transparent);
  border-color: color-mix(in srgb, #10b981 35%, transparent);
  color: var(--ink, #065f46);
}
.ux-banner.is-err {
  background: color-mix(in srgb, #ef4444 10%, transparent);
  border-color: color-mix(in srgb, #ef4444 30%, transparent);
  color: var(--ink, #991b1b);
}
.ux-banner .ux-banner-actions { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-top: 0.45rem; }
.drop-sample-prominent,
.dropzone .drop-sample,
.drop-actions .drop-ghost,
.dropzone .sample-link,
.drop-strip .drop-ghost {
  font-weight: 600 !important;
  text-decoration: underline;
  text-underline-offset: 3px;
}
body {
  padding-bottom: max(1.5rem, env(safe-area-inset-bottom));
}
@media (max-width: 480px) {
  body { padding-bottom: max(var(--sc-fb-pad, 72px), env(safe-area-inset-bottom)); }
  .batch-bar, #batchBar, .action-bar {
    padding-right: 4.25rem; /* leave room for feedback FAB */
  }
  .tool-stage, .paste-stage, .desk, .crt-bench, .studio, main {
    overflow-x: clip;
  }
}