:root {
  --bg:#ffffff; --bg-soft:#fafafa; --panel:#ffffff; --text:#17212b;
  --muted:#5f6b76; --line:#e6e8eb; --accent:#1c4f80; --shadow:0 10px 24px rgba(16,24,40,.04);
}
* { box-sizing:border-box; }
html { scroll-behavior:smooth; }
body {
  margin:0; font-family:Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color:var(--text); background:var(--bg);
}
a { color:inherit; text-decoration:none; }
img { display:block; max-width:100%; }
code { font-family:ui-monospace, SFMono-Regular, Menlo, monospace; }
.shell { width:min(1180px, calc(100% - 48px)); margin:0 auto; }
.narrow { width:min(920px, calc(100% - 48px)); }
.site-header {
  position:sticky; top:0; z-index:20; background:rgba(255,255,255,.94); border-bottom:1px solid var(--line);
}
.nav, .brand, .nav-links, .hero-actions, .contact-actions, .resource-links { display:flex; align-items:center; }
.nav { justify-content:space-between; min-height:74px; }
.brand { gap:12px; font-weight:700; letter-spacing:.02em; }
.brand img { width:38px; height:38px; object-fit:contain; border-radius:10px; }
.nav-links { gap:24px; color:var(--muted); font-size:.96rem; }
.nav-links a:hover { color:var(--accent); }
h1, h2, h3, p { margin:0; }
h1, h2 { font-family:ui-serif, Georgia, Cambria, "Times New Roman", serif; }
h1 { font-size:clamp(2.5rem, 4.6vw, 4.6rem); line-height:1.04; letter-spacing:-.04em; }
h2 { font-size:clamp(1.65rem, 2.8vw, 2.5rem); line-height:1.12; letter-spacing:-.03em; }
h3 { font-size:1.08rem; margin-bottom:10px; }
.eyebrow { margin:0 0 14px; color:var(--accent); text-transform:uppercase; letter-spacing:.16em; font-size:.75rem; font-weight:700; }
.hero { padding:72px 0 28px; }
.centered-copy { text-align:center; max-width:920px; margin:0 auto; }
.hero-subtitle, .authors, .affiliations, .prose p, .gallery-item figcaption, .contact-card p, .site-footer p, .muted, .simple-grid p, .applications-list div {
  color:var(--muted); line-height:1.74;
}
.hero-subtitle { margin:18px auto 0; font-size:1.12rem; max-width:56ch; }
.authors { margin-top:18px; font-weight:600; color:#253447; }
.author-emphasis { color:var(--text); font-weight:800; }
.author-focus { margin-top:10px; color:var(--accent); font-weight:700; letter-spacing:.01em; }
.affiliations { margin-top:8px; font-size:.98rem; }
.hero-actions { gap:14px; margin-top:26px; flex-wrap:wrap; justify-content:center; }
.button {
  padding:11px 17px; border-radius:999px; border:1px solid var(--line); background:#fff; color:var(--text);
  font-weight:600; transition:.22s ease;
}
.button:hover { transform:translateY(-1px); border-color:#cfd5dd; }
.button.primary { background:var(--text); color:#fff; border-color:var(--text); }
.hero-note { margin:22px auto 0; max-width:62ch; color:var(--muted); line-height:1.8; }
.hero-media { margin-top:40px; }
.figure-frame { border:1px solid var(--line); padding:18px; background:var(--bg-soft); }
.hero-media img { width:100%; height:auto; object-fit:contain; }
.section { padding:44px 0; }
.section-heading { max-width:780px; margin-bottom:22px; }
.section-heading.centered { text-align:center; margin-inline:auto; }
.section-heading.left { margin-bottom:16px; }
.statement-block { font-size:1.03rem; border-top:1px solid var(--line); padding-top:22px; }
.statement-block p + p, .prose p + p { margin-top:16px; }
.simple-grid, .gallery, .citation-grid, .two-column { display:grid; gap:26px; }
.simple-grid { grid-template-columns:repeat(3, minmax(0,1fr)); border-top:1px solid var(--line); padding-top:22px; }
.simple-grid article { padding-right:10px; }
.applications-list {
  display:grid; grid-template-columns:repeat(2, minmax(0,1fr)); gap:16px 28px;
  border-top:1px solid var(--line); padding-top:22px;
}
.gallery { grid-template-columns:1fr; align-items:start; max-width:880px; margin:0 auto; }
.gallery-item { margin:0; }
.gallery-item a { display:block; border:1px solid var(--line); background:var(--bg-soft); padding:12px; }
.gallery-item img { width:100%; height:auto; max-height:420px; object-fit:contain; border:none; margin:0 auto; }
.gallery-item figcaption { margin-top:14px; }
.two-column { grid-template-columns:.95fr 1.05fr; align-items:start; border-top:1px solid var(--line); padding-top:22px; }
.compact-title { margin-bottom:12px; }
.module-list { display:flex; flex-wrap:wrap; gap:10px 12px; }
.module-list span {
  border:1px solid var(--line); padding:8px 12px; font-size:.94rem; color:#314154; background:var(--bg-soft);
}
.citation-grid { grid-template-columns:1.15fr .85fr; align-items:start; }
.code-block pre {
  margin:0; white-space:pre-wrap; word-break:break-word; color:#243244; font-size:.94rem; line-height:1.75;
  font-family:ui-monospace, SFMono-Regular, Menlo, monospace;
}
.code-block { border-top:1px solid var(--line); padding-top:18px; }
.contact-card { position:sticky; top:96px; border-top:1px solid var(--line); padding-top:18px; }
.resource-links { flex-direction:column; align-items:flex-start; gap:12px; margin-top:18px; }
.resource-links a { color:var(--accent); font-weight:600; }
.resource-links a:hover { text-decoration:underline; }
.site-footer {
  display:flex; justify-content:space-between; gap:20px; padding:28px 0 56px; border-top:1px solid var(--line); margin-top:24px;
}
.manual-hero {
  padding:72px 0 34px;
  border-bottom:1px solid var(--line);
}
.manual-hero h1 { max-width:920px; }
.manual-hero .hero-subtitle { margin-left:0; max-width:880px; }
.manual-grid {
  display:grid;
  grid-template-columns:repeat(2, minmax(0, 1fr));
  gap:24px;
}
.manual-panel {
  border-top:1px solid var(--line);
  padding-top:18px;
}
.manual-panel h2,
.manual-panel h3 { margin-bottom:12px; }
.manual-panel p {
  color:var(--muted);
  line-height:1.75;
}
.manual-panel p + p { margin-top:12px; }
.manual-steps {
  margin:0;
  padding-left:22px;
  color:var(--muted);
  line-height:1.8;
}
.manual-code {
  margin-top:24px;
  background:var(--bg-soft);
  border:1px solid var(--line);
  padding:18px;
  overflow:auto;
}
.workflow-list {
  display:grid;
  grid-template-columns:1fr;
  gap:22px;
  border-top:1px solid var(--line);
  padding-top:22px;
}
.workflow-list article {
  display:grid;
  grid-template-columns:72px 1fr;
  gap:18px;
  align-items:start;
}
.workflow-list p {
  color:var(--muted);
  line-height:1.72;
}
.workflow-list p + p { margin-top:8px; }
.step-index {
  display:inline-flex;
  width:54px;
  height:54px;
  align-items:center;
  justify-content:center;
  border:1px solid var(--line);
  background:var(--bg-soft);
  color:var(--accent);
  font-weight:800;
}
.api-table {
  border-top:1px solid var(--line);
}
.api-row {
  display:grid;
  grid-template-columns:.9fr 1.1fr 1.1fr;
  gap:18px;
  padding:16px 0;
  border-bottom:1px solid var(--line);
  color:var(--muted);
  line-height:1.65;
}
.api-row span:first-child {
  color:var(--text);
  font-weight:700;
}
.api-head {
  color:var(--text);
  font-size:.82rem;
  text-transform:uppercase;
  letter-spacing:.08em;
  font-weight:800;
}
.api-table.compact .api-row {
  grid-template-columns:1fr 1.05fr 1.05fr;
}
.tutorial-grid {
  display:grid;
  grid-template-columns:repeat(3, minmax(0, 1fr));
  gap:16px;
}
.tutorial-card {
  display:block;
  border:1px solid var(--line);
  background:var(--bg-soft);
  padding:18px;
  transition:.22s ease;
}
.tutorial-card:hover {
  transform:translateY(-2px);
  border-color:#cfd5dd;
  background:#fff;
}
.tutorial-card span {
  color:var(--accent);
  font-size:.76rem;
  font-weight:800;
  letter-spacing:.12em;
  text-transform:uppercase;
}
.tutorial-card h3 {
  margin-top:8px;
}
.tutorial-card p {
  color:var(--muted);
  line-height:1.65;
}
.manual-book {
  background:#fff;
}
.manual-topbar {
  position:sticky;
  top:0;
  z-index:30;
  background:#fff;
  border-bottom:1px solid var(--line);
}
.manual-topbar-inner {
  min-height:68px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:18px;
}
.manual-switch {
  display:flex;
  gap:8px;
  align-items:center;
}
.manual-switch a {
  border:1px solid var(--line);
  padding:8px 12px;
  font-weight:700;
  color:var(--muted);
  background:#fff;
}
.manual-switch a.active {
  color:#fff;
  background:var(--text);
  border-color:var(--text);
}
.manual-layout {
  display:grid;
  grid-template-columns:250px minmax(0, 1fr);
  gap:44px;
  align-items:start;
  padding:34px 0 76px;
}
.manual-toc {
  position:sticky;
  top:94px;
  border-right:1px solid var(--line);
  padding-right:22px;
  max-height:calc(100vh - 120px);
  overflow:auto;
}
.toc-title {
  margin:0 0 14px;
  color:var(--text);
  font-weight:800;
  letter-spacing:.06em;
  text-transform:uppercase;
  font-size:.76rem;
}
.manual-toc a {
  display:block;
  padding:7px 0;
  color:var(--muted);
  line-height:1.35;
  font-size:.94rem;
}
.manual-toc a:hover {
  color:var(--accent);
}
.manual-content {
  max-width:900px;
}
.manual-content section {
  padding:28px 0;
  border-bottom:1px solid var(--line);
  scroll-margin-top:92px;
}
.manual-content .manual-title {
  padding-top:0;
}
.manual-title h1 {
  margin-bottom:16px;
}
.manual-content h2 {
  font-family:ui-serif, Georgia, Cambria, "Times New Roman", serif;
  font-size:2rem;
  line-height:1.2;
  margin-bottom:18px;
}
.manual-content h3 {
  margin:22px 0 10px;
  font-size:1.12rem;
}
.manual-content p,
.manual-content li {
  color:var(--muted);
  line-height:1.78;
}
.manual-content p + p {
  margin-top:12px;
}
.manual-content .tutorial-ref {
  display:inline-block;
  margin:0 0 14px;
  padding:8px 12px;
  border:1px solid var(--line);
  background:var(--bg-soft);
  color:var(--muted);
  font-size:.95rem;
}
.tutorial-ref a {
  color:var(--accent);
  font-weight:800;
}
.tutorial-ref a:hover {
  text-decoration:underline;
}
.manual-content ul,
.manual-content ol {
  margin:12px 0 0;
  padding-left:22px;
}
.manual-content pre {
  margin:16px 0;
  padding:16px;
  overflow:auto;
  background:#f7f8fa;
  border:1px solid var(--line);
  color:#253447;
  line-height:1.58;
  font-size:.93rem;
}
.manual-content pre code {
  white-space:pre;
}
.manual-content table {
  width:100%;
  border-collapse:collapse;
  margin-top:16px;
  font-size:.95rem;
}
.manual-content th,
.manual-content td {
  border-bottom:1px solid var(--line);
  padding:12px 10px;
  text-align:left;
  vertical-align:top;
}
.manual-content th {
  color:var(--text);
  background:var(--bg-soft);
}
.manual-content td {
  color:var(--muted);
  line-height:1.65;
}
@media (max-width: 980px) {
  .gallery, .two-column, .citation-grid { grid-template-columns:1fr; }
  .simple-grid, .applications-list, .manual-grid { grid-template-columns:repeat(2, minmax(0,1fr)); }
  .tutorial-grid { grid-template-columns:repeat(2, minmax(0,1fr)); }
  .api-row,
  .api-table.compact .api-row { grid-template-columns:1fr; gap:6px; }
  .contact-card { position:static; }
  .nav { flex-direction:column; justify-content:center; gap:14px; padding:14px 0; }
  .manual-layout { grid-template-columns:1fr; gap:24px; }
  .manual-toc {
    position:static;
    max-height:none;
    border-right:0;
    border-bottom:1px solid var(--line);
    padding:0 0 18px;
    display:grid;
    grid-template-columns:repeat(2, minmax(0, 1fr));
    gap:2px 18px;
  }
  .toc-title { grid-column:1 / -1; }
}
@media (max-width: 720px) {
  .shell, .narrow { width:min(100% - 28px, 1180px); }
  .nav-links, .simple-grid, .applications-list, .manual-grid, .tutorial-grid, .site-footer { display:grid; grid-template-columns:1fr; }
  .nav-links { gap:10px; text-align:center; }
  .manual-hero { padding-top:42px; }
  .manual-topbar-inner { flex-direction:column; align-items:flex-start; padding:14px 0; }
  .manual-switch { flex-wrap:wrap; }
  .manual-toc { grid-template-columns:1fr; }
  .manual-content h2 { font-size:1.65rem; }
  .workflow-list article { grid-template-columns:1fr; gap:10px; }
  .site-footer { padding-bottom:42px; }
}

/* Product-system manual skin: shared by the Chinese and English manuals. */
body.manual-book {
  --manual-ink:#07101f;
  --manual-panel:#0b1730;
  --manual-line:rgba(205,224,255,.16);
  --manual-muted:#a8b8d1;
  background:var(--manual-ink);
  color:#f6f9ff;
}
.manual-book .manual-topbar { background:rgba(7,16,31,.84); border-color:var(--manual-line); backdrop-filter:blur(18px); }
.manual-book .brand { color:#f6f9ff; }
.manual-book .brand img { width:36px; height:36px; border-radius:9px; }
.manual-book .manual-switch a { border-color:var(--manual-line); background:transparent; color:#b7c6dd; border-radius:999px; }
.manual-book .manual-switch a.active { background:#76f0dd; border-color:#76f0dd; color:#061725; }
.manual-book .manual-layout { grid-template-columns:260px minmax(0,1fr); }
.manual-book .manual-toc { border-color:var(--manual-line); }
.manual-book .toc-title { color:#76f0dd; }
.manual-book .manual-toc a { color:#9fb1cc; }
.manual-book .manual-toc a:hover { color:#76f0dd; }
.manual-book .manual-content { max-width:900px; }
.manual-book .manual-content section { border-color:var(--manual-line); }
.manual-book .manual-content h1,
.manual-book .manual-content h2 { color:#f6f9ff; }
.manual-book .manual-content h1 { font-size:clamp(3rem,5vw,4.8rem); letter-spacing:-.055em; line-height:.96; }
.manual-book .manual-content h2 { font-size:clamp(1.7rem,3vw,2.35rem); letter-spacing:-.035em; }
.manual-book .manual-content h3 { color:#dfeaff; }
.manual-book .manual-content p,
.manual-book .manual-content li,
.manual-book .manual-content td { color:var(--manual-muted); }
.manual-book .manual-content code { color:#a9f5e9; }
.manual-book .manual-content pre,
.manual-book .manual-code { background:#09172b; border-color:var(--manual-line); color:#dceaff; box-shadow:inset 0 1px 0 rgba(255,255,255,.03); }
.manual-book .manual-content pre code { color:#dceaff; }
.manual-book .manual-content th { background:#112442; color:#f6f9ff; border-color:var(--manual-line); }
.manual-book .manual-content th,
.manual-book .manual-content td { border-color:var(--manual-line); }
.manual-book .tutorial-ref { border-color:rgba(118,240,221,.35); background:rgba(118,240,221,.08); color:#b8cee8; border-radius:8px; }
.manual-book .tutorial-ref a { color:#76f0dd; }
.manual-book .manual-title { padding:30px 0 48px!important; border-bottom:1px solid var(--manual-line)!important; }
.manual-book .manual-title .eyebrow { color:#76f0dd; }
.manual-book .manual-title > p:last-child { max-width:720px; margin-top:20px; font-size:1.05rem; line-height:1.8; }
.manual-book .manual-title::after { content:"PHYSICS-NATIVE · OPEN SCIENTIFIC SOFTWARE"; display:inline-block; margin-top:24px; color:#76f0dd; font-size:.72rem; letter-spacing:.13em; font-weight:800; }
.manual-book .manual-hero-actions { display:flex; flex-wrap:wrap; gap:10px; margin-top:25px; }
.manual-book .manual-hero-actions a { padding:10px 14px; border:1px solid var(--manual-line); border-radius:999px; color:#dbe8fc; font-size:.86rem; font-weight:750; }
.manual-book .manual-hero-actions a:first-child { background:#76f0dd; border-color:#76f0dd; color:#061725; }
.manual-book .manual-hero-actions a:hover { border-color:#76f0dd; transform:translateY(-1px); }
@media (max-width:980px) {
  .manual-book .manual-layout { grid-template-columns:1fr; }
  .manual-book .manual-toc { border-color:var(--manual-line); }
}

/* Bright companion theme for the product launch site and manuals. */
body.manual-book { --manual-ink:#f7fbff; --manual-panel:#ffffff; --manual-line:#d9e7f2; --manual-muted:#576e85; background:var(--manual-ink); color:#142b45; }
.manual-book .manual-topbar { background:rgba(255,255,255,.88); border-color:var(--manual-line); }
.manual-book .brand { color:#142b45; }
.manual-book .manual-switch a { border-color:#d3e2ef; background:#f5faff; color:#58718b; }
.manual-book .manual-switch a.active { background:#1680d9; border-color:#1680d9; color:#fff; }
.manual-book .manual-toc { border-color:var(--manual-line); }
.manual-book .toc-title { color:#1680d9; }
.manual-book .manual-toc a { color:#58718b; }
.manual-book .manual-toc a:hover { color:#1680d9; }
.manual-book .manual-content section { border-color:var(--manual-line); }
.manual-book .manual-content h1,.manual-book .manual-content h2,.manual-book .manual-content h3 { color:#142b45; }
.manual-book .manual-content p,.manual-book .manual-content li,.manual-book .manual-content td { color:var(--manual-muted); }
.manual-book .manual-content code { color:#087d70; }
.manual-book .manual-content pre,.manual-book .manual-code { background:#f1f8fd; border-color:#d8e7f2; color:#173652; box-shadow:none; }
.manual-book .manual-content pre code { color:#173652; }
.manual-book .manual-content th { background:#e9f5fd; color:#173652; border-color:var(--manual-line); }
.manual-book .manual-content th,.manual-book .manual-content td { border-color:var(--manual-line); }
.manual-book .tutorial-ref { border-color:#bfe4dc; background:#effcf8; color:#507186; }
.manual-book .tutorial-ref a,.manual-book .manual-title .eyebrow { color:#087d70; }
.manual-book .manual-title { border-color:var(--manual-line)!important; }
.manual-book .manual-title::after { color:#1680d9; }
.manual-book .manual-hero-actions a { border-color:#d0e2ef; color:#29516f; background:#fff; }
.manual-book .manual-hero-actions a:first-child { background:#1680d9; border-color:#1680d9; color:#fff; }
.manual-book .manual-hero-actions a:hover { border-color:#1680d9; }