/* ==============================================================
   F(AI)^2R site — built on the DLR Corporate Design tokens
   (CD-Handbuch §10.1 Typografie, §4 Printmedien, layout rules).
   --------------------------------------------------------------
   Primary token sheet: dlr/colors_and_type.css
     - Frutiger / Arial stack
     - Colour ramps (blue, green, yellow, grey)
     - Spacing, radii, shadow tokens
     - Variant switching: <html data-variant="b"|"c">

   Per CD-Handbuch §10.1, "Elektronischer Dokumentenaustausch"
   (E-Mail, Web, PowerPoint) uses Arial; Frutiger is reserved for
   Drucksachen. The stack below realises that rule automatically:
   if the Frutiger faces are not vendored to /static/dlr/fonts/,
   Arial is served.
   ============================================================== */
@import url("dlr/colors_and_type.css");

/* ------- Page chrome (DLR website kit, simplified) ------------ */
* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  font-size: var(--type-body);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;            /* prevent rogue elements forcing horizontal scroll on phones */
  -webkit-text-size-adjust: 100%; /* don't auto-inflate text on iOS landscape */
}
img, svg, video, iframe, canvas { max-width: 100%; height: auto; }

a {
  color: var(--dlr-link);
  text-decoration: underline;
  text-underline-offset: 2px;
}
a:hover { color: var(--accent); }

/* ------- Top utility bar (mid-grey, lang switch placeholder) -- */
.utility {
  background: var(--dlr-grau-5);
  border-bottom: 1px solid var(--border);
  font-size: 12px;
  color: #464646;
}
.utility .inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 6px 32px;
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 18px;
}
.utility a { color: #464646; text-decoration: none; }
.utility a:hover { color: var(--accent); }

/* ------- Header: DLR logo (institute imprint), org line ------- */
.header { background: var(--bg); border-bottom: 1px solid var(--border); }
.header .inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 18px 32px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.header .logo { height: 48px; flex-shrink: 0; }
.header .org-line {
  font-size: 12px;
  color: var(--fg-2);
  line-height: 1.35;
  flex: 1;
}
.header .org-line .big {
  display: block;
  font-weight: 700;
  color: var(--fg);
  font-size: 14px;
  letter-spacing: -0.005em;
}

/* ------- Primary navigation: DLR Blue band ------------------- */
.nav { background: var(--accent); }
.nav .inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  flex-wrap: wrap;
}
.nav a {
  color: #fff;
  padding: 12px 16px;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  letter-spacing: 0.005em;
}
.nav a:hover { background: rgba(255, 255, 255, 0.12); color: #fff; }
.nav a.active { background: rgba(0, 0, 0, 0.18); color: #fff; }

/* ------- Hero: tight, square, no gradients in chrome --------- */
.hero {
  background: var(--bg-soft);
  border-bottom: 1px solid var(--border);
}
.hero .inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 36px 32px 28px;
}
.hero .eyebrow {
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--fg-2);
  font-weight: 700;
}
.hero h1 {
  font-size: 36px;
  line-height: 1.1;
  margin: 8px 0 6px;
  color: var(--fg-2);
  font-weight: 700;
  letter-spacing: -0.005em;
}
.hero .lede {
  font-size: 17px;
  max-width: 64ch;
  margin: 6px 0 0;
  color: var(--fg);
  line-height: 1.5;
}

.hero .build-tag {
  margin-top: 8px;
  font-family: var(--font-sans);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--fg-mute);
  text-transform: uppercase;
}
.hero .build-tag code {
  font-family: var(--font-mono);
  font-size: 11px;
  background: transparent;
  border: 0;
  padding: 0;
  color: var(--accent);
}

/* ------- Main content area ----------------------------------- */
main {
  max-width: 1280px;
  margin: 0 auto;
  padding: 28px 32px 64px;
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: 40px;
}

@media (max-width: 900px) {
  /* Tablet portrait: collapse the two-column main into a single
     column, tighten outer padding, allow nav to wrap. */
  .header .inner,
  .nav .inner,
  .hero .inner,
  main,
  footer .inner,
  .utility .inner { padding-left: 18px; padding-right: 18px; }

  main { grid-template-columns: 1fr; gap: 18px; padding-top: 22px; padding-bottom: 56px; }

  /* Sidebar moves below content on tablets so the article gets
     full width; sidebar stays useful as a footer-style index. */
  .sidebar { order: 2; }
  .content { order: 1; }

  .nav .inner { flex-wrap: wrap; gap: 0; }
  .nav a { padding: 10px 14px; font-size: 13px; }

  .hero h1 { font-size: 30px; }
  .hero .lede { font-size: 16px; }

  /* Tables on tablets: still scroll if needed */
  .content table { display: block; overflow-x: auto; -webkit-overflow-scrolling: touch; }
}

/* ------- Sidebar / breadcrumb-like local nav ----------------- */
.sidebar {
  font-size: 13px;
  border-top: 1px solid var(--border);
}
.sidebar h4 {
  font-size: 12px;
  color: var(--fg-2);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin: 16px 0 8px;
  font-weight: 700;
}
.sidebar ul { list-style: none; padding: 0; margin: 0 0 16px; }
.sidebar li { border-bottom: 1px solid var(--border); }
.sidebar a {
  display: block;
  padding: 9px 0;
  color: var(--fg);
  text-decoration: none;
  font-size: 13px;
}
.sidebar a:hover { color: var(--accent); }
.sidebar a.active {
  color: var(--accent);
  font-weight: 700;
  border-left: 3px solid var(--accent);
  padding-left: 10px;
  margin-left: -13px;
}

/* ------- Article: H1 mid-grey, H2 in accent, H3 dark ---------- */
.content h1 {
  font-size: 30px;
  color: var(--fg-2);
  margin: 0 0 14px;
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.005em;
}
.content h2 {
  font-size: 21px;
  color: var(--accent);
  margin: 30px 0 10px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.003em;
  border-top: 1px solid var(--border);
  padding-top: 14px;
}
.content h2:first-of-type { border-top: 0; padding-top: 0; }
.content h3 {
  font-size: 16px;
  color: var(--fg-3);
  margin: 22px 0 6px;
  font-weight: 700;
}
.content h4 {
  font-size: 14px;
  color: var(--fg-3);
  margin: 18px 0 4px;
  font-weight: 700;
  letter-spacing: 0.005em;
}

.content p { font-size: 15px; line-height: 1.6; color: var(--fg); margin: 0 0 12px; }
.content ul, .content ol { padding-left: 1.4em; margin: 0 0 12px; }
.content li { margin: 4px 0; line-height: 1.55; }
.content blockquote {
  border-left: 4px solid var(--accent);
  margin: 14px 0;
  padding: 6px 16px;
  color: var(--fg-2);
  font-style: italic;
  font-size: 15px;
}

/* ------- Lede paragraph (under hero, on Home) ----------------- */
.content .lede {
  font-size: 17px;
  color: var(--fg);
  margin-bottom: 18px;
  line-height: 1.5;
}

/* ------- Code / mono ----------------------------------------- */
code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--dlr-grau-5);
  padding: 0.05em 0.35em;
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-1);
}
pre {
  font-family: var(--font-mono);
  background: var(--bg-soft);
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-1);
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.5;
  margin: 14px 0;
}
pre code { background: none; border: 0; padding: 0; }

/* ------- Tables: hairline borders, mid-grey header ------------ */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 14px;
}
table th, table td {
  text-align: left;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
table th {
  background: var(--dlr-grau-5);
  font-weight: 700;
  color: var(--fg-3);
  border-bottom: 1px solid var(--border);
  font-size: 13px;
  letter-spacing: 0.005em;
}
table td code { font-size: 0.86em; }

/* ------- Callout / facts strip -------------------------------- */
.callout {
  background: var(--dlr-grau-5);
  border-left: 4px solid var(--accent);
  padding: 12px 16px;
  margin: 14px 0;
  font-size: 14px;
  color: var(--fg);
}

/* ------- Footer: dark grey ribbon (DLR convention) ------------ */
footer {
  background: #464646;
  color: #fff;
  padding: 28px 0 12px;
  margin-top: 48px;
}
footer .inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 32px;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 28px;
}
footer h4 {
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin: 0 0 10px;
  color: #fff;
  font-weight: 700;
}
footer p, footer a {
  color: var(--dlr-blau-5);
  font-size: 13px;
  line-height: 1.55;
  text-decoration: none;
}
footer a:hover { color: #fff; text-decoration: underline; }
footer .legal {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  margin-top: 16px;
  padding: 14px 0;
  background: #2b2b2b;
  color: var(--dlr-grau-3);
  font-size: 12px;
}
footer .legal .inner {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  justify-content: space-between;
}
footer .legal a { color: var(--dlr-grau-3); }
footer .legal a:hover { color: #fff; }

@media (max-width: 720px) {
  footer .inner { grid-template-columns: 1fr; }
}

/* ------- Mermaid diagrams: leave room ------------------------- */
.mermaid { margin: 18px 0; text-align: center; }

/* ------- Hero call-to-action row (Home page) ------------------ */
.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 18px 0 8px;
}
.cta {
  display: inline-block;
  padding: 11px 22px;
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 700;
  border: 1px solid transparent;
  text-decoration: none;
  line-height: 1.1;
  letter-spacing: 0.01em;
}
.cta.primary {
  background: var(--accent);
  color: #fff;
}
.cta.primary:hover { background: #004f6e; color: #fff; }
.cta.secondary {
  background: transparent;
  color: var(--accent);
  border-color: var(--accent);
}
.cta.secondary:hover {
  background: var(--dlr-blau-5);
  color: var(--accent);
}
.cta.tertiary {
  background: var(--dlr-grau-5);
  color: var(--fg);
  border-color: var(--border);
}
.cta.tertiary:hover { background: var(--dlr-grau-4); color: var(--fg); }
.cta:active { transform: translateY(1px); }

/* ------- Card grid (DLR pattern, used on the homepage) -------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin: 18px 0 24px;
}
@media (max-width: 720px) { .card-grid { grid-template-columns: 1fr; } }
.dlr-card {
  border: 1px solid var(--border);
  background: #fff;
  display: flex;
  flex-direction: column;
}
.dlr-card .body {
  padding: 16px 18px 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
}
.dlr-card .eyebrow {
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--fg-2);
  font-weight: 700;
}
.dlr-card h3 {
  font-size: 16px !important;
  color: var(--fg) !important;
  margin: 6px 0 8px !important;
  line-height: 1.3;
}
.dlr-card p {
  font-size: 13px !important;
  color: var(--fg-3);
  line-height: 1.5;
  margin: 0 0 14px;
  flex: 1;
}
.dlr-card .more {
  font-size: 13px;
  color: var(--accent);
  font-weight: 700;
  text-decoration: none;
  margin-top: auto;
}
.dlr-card .more:hover { text-decoration: underline; }
.dlr-card:hover { box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08); }

/* ------- Provenance explorer canvas --------------------------- */
#prov-explorer {
  width: 100%;
  height: 600px;
  border: 1px solid var(--border);
  background: var(--bg);
  margin: 16px 0;
}
.prov-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin: 8px 0 14px;
  align-items: center;
  font-family: var(--font-sans);
  font-size: 13px;
}
.prov-controls label { color: var(--fg-2); }
.prov-controls select, .prov-controls input[type="text"] {
  border: 1px solid var(--border);
  padding: 6px 10px;
  font: inherit;
  background: var(--bg);
  color: var(--fg);
}
.prov-info {
  background: var(--dlr-grau-5);
  border: 1px solid var(--border);
  padding: 12px 16px;
  margin: 8px 0;
  font-size: 13px;
  color: var(--fg);
  min-height: 60px;
}
.prov-info code { font-size: 0.9em; }

/* ------- Responsive defaults: never overflow the viewport ----- */
.content img,
.content video,
.content iframe { max-width: 100%; height: auto; }
.content pre { overflow-x: auto; }
.content figure { margin: 16px 0; }

/* ------- Mobile breakpoint (phones) -------------------------- */
@media (max-width: 720px) {
  /* Tighter horizontal padding everywhere */
  .header .inner,
  .nav .inner,
  .hero .inner,
  main,
  footer .inner,
  .utility .inner { padding-left: 16px; padding-right: 16px; }

  /* Header: stack logo + org-line, smaller type */
  .header .inner { flex-direction: column; align-items: flex-start; gap: 10px; padding-top: 12px; padding-bottom: 12px; }
  .header .logo { height: 40px; }
  .header .org-line { font-size: 12px; line-height: 1.4; }
  .header .org-line .big { font-size: 14px; display: block; margin-bottom: 2px; }

  /* Utility ribbon: tighter */
  .utility .inner { gap: 12px; font-size: 12px; flex-wrap: wrap; }

  /* Nav: allow wrap to a second row rather than overflowing */
  .nav .inner { flex-wrap: wrap; gap: 0; }
  .nav a { padding: 10px 12px; font-size: 13px; flex-shrink: 0; }

  /* Hero: smaller h1, tighter padding */
  .hero .inner { padding: 22px 16px 18px; }
  .hero h1 { font-size: 26px; }
  .hero .lede { font-size: 15px; }
  .hero .eyebrow { font-size: 11px; }

  /* Main: drop the 28px / 32px desktop margins */
  main { padding: 20px 16px 48px; gap: 12px; }

  /* Article body: smaller headings */
  .content h1 { font-size: 24px; }
  .content h2 { font-size: 18px; margin-top: 22px; padding-top: 14px; }
  .content h3 { font-size: 16px; }
  .content p { font-size: 15px; }

  /* CTAs: full width on phones, stacked */
  .cta-row { flex-direction: column; }
  .cta { width: 100%; text-align: center; box-sizing: border-box; }

  /* Tables: scroll horizontally inside a container rather than
     blowing the viewport */
  .content table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    font-size: 13px;
  }
  .content table th,
  .content table td { padding: 6px 8px; }

  /* Mermaid client-side render: scroll on overflow */
  .mermaid { overflow-x: auto; }

  /* Sidebar typography */
  .sidebar { font-size: 13px; padding-top: 0; }
  .sidebar h4 { margin-top: 12px; }
}

/* ------- Very narrow phones (iPhone SE, ~375 px) ------------- */
@media (max-width: 380px) {
  .hero h1 { font-size: 22px; }
  .nav a { padding: 8px 10px; font-size: 12px; }
  .header .org-line .big { font-size: 13px; }
}

/* ------- Print: no DLR footer ribbon, clean ------------------- */
@media print {
  .nav, footer, .utility { display: none; }
  body { font-size: 11pt; }
  .content h2 { color: var(--fg-2); border-top-color: #000; }
}
