/* ============================================================
   base.css — Design-Tokens & Buch-Look (Schicht 1: Stil)
   ki-visibility.com · Cover-Ästhetik: Dunkelblau/Schwarz,
   leuchtendes Blau, Lupe, Netzwerkpartikel.
   Reines CSS, systemeigene Schriften (0 externe Requests).
   ============================================================ */

:root {
  /* --- Farben: Cover --- */
  --bg-0: #04060f;           /* tiefstes Nachtblau/Schwarz */
  --bg-1: #070b1a;
  --bg-2: #0c1228;
  --bg-panel: rgba(12, 20, 46, 0.72);
  --bg-panel-solid: #0b1330;

  --ink: #eaf0ff;            /* Haupttext, fast weiß */
  --ink-soft: #b9c4e6;
  --muted: #7c88b0;          /* Sekundärtext */
  --line: rgba(120, 150, 230, 0.16);

  --accent: #37a6ff;         /* leuchtendes Blau */
  --accent-bright: #6fd0ff;  /* Glow-Highlight */
  --accent-deep: #1b5fd9;
  --accent-glow: rgba(55, 166, 255, 0.55);
  --gold: #ffd479;           /* PowerUp / Akzent Lupe */

  /* --- Typografie --- */
  --font-display: "Iowan Old Style", "Palatino Linotype", Palatino,
                  "Book Antiqua", Georgia, "Times New Roman", serif;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
               "Helvetica Neue", Arial, system-ui, sans-serif;
  --font-mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, monospace;

  /* --- Maße --- */
  --maxw: 74ch;
  --maxw-wide: 1120px;
  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 18px 50px -20px rgba(0, 0, 0, 0.8);
  --shadow-glow: 0 0 0 1px var(--line), 0 20px 60px -24px var(--accent-glow);

  --space: clamp(1rem, 0.6rem + 1.6vw, 1.6rem);
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: clamp(1rem, 0.96rem + 0.25vw, 1.125rem);
  line-height: 1.72;
  color: var(--ink-soft);
  background:
    radial-gradient(1200px 700px at 78% -8%, rgba(31, 95, 217, 0.20), transparent 60%),
    radial-gradient(900px 600px at 8% 12%, rgba(55, 166, 255, 0.10), transparent 55%),
    linear-gradient(180deg, var(--bg-1) 0%, var(--bg-0) 55%, #02030a 100%);
  background-attachment: fixed;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Feiner Netzwerk-Partikel-Layer über dem ganzen Body */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    radial-gradient(1.5px 1.5px at 20% 30%, rgba(111, 208, 255, 0.7), transparent),
    radial-gradient(1.5px 1.5px at 68% 18%, rgba(111, 208, 255, 0.5), transparent),
    radial-gradient(1px 1px at 42% 72%, rgba(255, 255, 255, 0.5), transparent),
    radial-gradient(1.5px 1.5px at 85% 62%, rgba(55, 166, 255, 0.6), transparent),
    radial-gradient(1px 1px at 12% 82%, rgba(111, 208, 255, 0.5), transparent),
    radial-gradient(1px 1px at 55% 45%, rgba(255, 255, 255, 0.35), transparent);
  background-size: 100% 100%;
  opacity: 0.7;
  animation: drift 42s linear infinite alternate;
}

@keyframes drift {
  from { transform: translate3d(0, 0, 0); }
  to   { transform: translate3d(-24px, -18px, 0); }
}

/* --- Typo-Rhythmus --- */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--ink);
  line-height: 1.15;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 0 0 0.5em;
}
h1 { font-size: clamp(2.1rem, 1.4rem + 3.4vw, 3.6rem); }
h2 { font-size: clamp(1.5rem, 1.15rem + 1.7vw, 2.15rem); margin-top: 2.2em; }
h3 { font-size: clamp(1.2rem, 1.05rem + 0.8vw, 1.45rem); margin-top: 1.6em; }

p { margin: 0 0 1.15em; }

a { color: var(--accent-bright); text-underline-offset: 3px; text-decoration-color: var(--accent-glow); }
a:hover { color: #fff; }

strong { color: var(--ink); }

::selection { background: var(--accent-deep); color: #fff; }

/* --- Layout-Wrapper --- */
.wrap { width: min(100% - 2 * var(--space), var(--maxw-wide)); margin-inline: auto; }
.prose { max-width: var(--maxw); }

/* ============================================================
   Header / Nav
   ============================================================ */
.site-header {
  position: sticky; top: 0; z-index: 40;
  backdrop-filter: blur(14px);
  background: linear-gradient(180deg, rgba(4, 6, 15, 0.9), rgba(4, 6, 15, 0.55));
  border-bottom: 1px solid var(--line);
}
.site-header .wrap {
  display: flex; align-items: center; gap: 1rem;
  padding-block: 0.75rem;
}
.brand {
  display: inline-flex; align-items: center; gap: 0.6rem;
  font-family: var(--font-display); font-weight: 600; font-size: 1.15rem;
  color: var(--ink); text-decoration: none; letter-spacing: -0.01em;
}
.brand .lens {
  width: 26px; height: 26px; flex: none;
  filter: drop-shadow(0 0 6px var(--accent-glow));
}
.brand b { color: var(--accent-bright); font-weight: 600; }

.main-nav { margin-left: auto; display: flex; gap: 0.25rem; flex-wrap: wrap; }
.main-nav a {
  color: var(--ink-soft); text-decoration: none; font-size: 0.92rem;
  padding: 0.4rem 0.7rem; border-radius: 99px; font-family: var(--font-body);
}
.main-nav a:hover, .main-nav a[aria-current="page"] {
  color: #fff; background: rgba(55, 166, 255, 0.14);
}

/* ============================================================
   Buttons / CTA
   ============================================================ */
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  font-family: var(--font-body); font-weight: 600; font-size: 0.98rem;
  padding: 0.72rem 1.25rem; border-radius: 99px;
  text-decoration: none; cursor: pointer; border: 1px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease;
}
.btn-primary {
  color: #04122b;
  background: linear-gradient(180deg, var(--accent-bright), var(--accent));
  box-shadow: 0 10px 30px -10px var(--accent-glow), inset 0 1px 0 rgba(255,255,255,0.4);
}
.btn-primary:hover { transform: translateY(-2px); color: #04122b; box-shadow: 0 16px 40px -12px var(--accent-glow); }
.btn-ghost {
  color: var(--ink); background: rgba(255,255,255,0.03);
  border-color: var(--line);
}
.btn-ghost:hover { border-color: var(--accent); color: #fff; background: rgba(55,166,255,0.10); }

/* ============================================================
   Hero (Pillar)
   ============================================================ */
.hero { position: relative; padding: clamp(3rem, 2rem + 6vw, 6rem) 0 2rem; }
.hero .eyebrow {
  text-transform: uppercase; letter-spacing: 0.22em; font-size: 0.76rem;
  color: var(--accent-bright); font-weight: 700; margin-bottom: 1rem;
}
.hero h1 { max-width: 18ch; }
.hero .lead { font-size: clamp(1.1rem, 1rem + 0.7vw, 1.4rem); color: var(--ink-soft); max-width: 52ch; }
.hero-cta { display: flex; gap: 0.75rem; flex-wrap: wrap; margin-top: 1.8rem; }

/* Direkt-Antwort (zitierfähiger Chunk) */
.answer-box {
  border-left: 3px solid var(--accent);
  background: var(--bg-panel);
  border-radius: var(--radius-sm);
  padding: 1.1rem 1.3rem;
  margin: 1.8rem 0;
  box-shadow: var(--shadow);
}
.answer-box p:last-child { margin-bottom: 0; }
.answer-box .tag {
  display: inline-block; font-size: 0.72rem; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--accent-bright); margin-bottom: 0.5rem; font-weight: 700;
}

/* ============================================================
   Content / Prose Bausteine
   ============================================================ */
.section { padding-block: clamp(2rem, 1rem + 4vw, 3.5rem); }

figure.stat, .callout {
  margin: 1.6rem 0; padding: 1rem 1.2rem;
  background: rgba(55, 166, 255, 0.06);
  border: 1px solid var(--line); border-radius: var(--radius-sm);
}
.callout .who { color: var(--accent-bright); font-weight: 600; }
blockquote {
  margin: 1.6rem 0; padding: 0.4rem 0 0.4rem 1.2rem;
  border-left: 3px solid var(--gold); color: var(--ink);
  font-family: var(--font-display); font-size: 1.15rem; font-style: italic;
}
blockquote cite { display: block; font-size: 0.9rem; color: var(--muted); font-style: normal; margin-top: 0.5rem; }

table {
  width: 100%; border-collapse: collapse; margin: 1.6rem 0; font-size: 0.95rem;
  background: var(--bg-panel); border-radius: var(--radius-sm); overflow: hidden;
}
caption { text-align: left; color: var(--muted); font-size: 0.85rem; margin-bottom: 0.5rem; }
th, td { padding: 0.7rem 0.9rem; text-align: left; border-bottom: 1px solid var(--line); }
thead th { color: var(--ink); background: rgba(55,166,255,0.10); font-family: var(--font-body); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.05em; }
tbody tr:last-child td { border-bottom: none; }

/* FAQ / details */
.faq details {
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  margin-bottom: 0.7rem; background: var(--bg-panel); overflow: hidden;
}
.faq summary {
  cursor: pointer; padding: 0.95rem 1.1rem; font-weight: 600; color: var(--ink);
  font-family: var(--font-display); font-size: 1.05rem; list-style: none;
  display: flex; justify-content: space-between; align-items: center; gap: 1rem;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "＋"; color: var(--accent); font-weight: 400; transition: transform 0.2s; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details > p { padding: 0 1.1rem 1.1rem; margin: 0; color: var(--ink-soft); }

/* CTA-Band */
.cta-band {
  margin: 3rem 0; padding: clamp(1.6rem, 1rem + 3vw, 2.6rem);
  border-radius: var(--radius); text-align: center;
  background:
    radial-gradient(600px 200px at 50% 0%, rgba(55,166,255,0.25), transparent 70%),
    var(--bg-panel-solid);
  border: 1px solid var(--line); box-shadow: var(--shadow-glow);
}
.cta-band h2 { margin-top: 0; }
.cta-band p { max-width: 46ch; margin-inline: auto; }

/* ============================================================
   Das KI-Viertel — flaches Billboard-Grid (crawlbar/tastatur)
   ============================================================ */
.quarter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 0.9rem; margin-top: 1.5rem;
}
.quarter-grid a {
  display: block; text-decoration: none; color: var(--ink);
  background: var(--bg-panel); border: 1px solid var(--line);
  border-radius: var(--radius-sm); padding: 1rem 1.1rem;
  transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}
.quarter-grid a:hover, .quarter-grid a:focus-visible {
  border-color: var(--accent); transform: translateY(-3px);
  box-shadow: 0 14px 34px -18px var(--accent-glow); outline: none;
}
.quarter-grid .q-num {
  font-family: var(--font-mono); font-size: 0.72rem; color: var(--accent-bright);
  letter-spacing: 0.1em;
}
.quarter-grid b { display: block; color: #fff; font-family: var(--font-display); font-size: 1.1rem; margin: 0.15rem 0 0.35rem; }
.quarter-grid span:last-child { display: block; color: var(--muted); font-size: 0.86rem; line-height: 1.45; }
.quarter-grid .oracle-link { background: linear-gradient(160deg, rgba(255,212,121,0.10), var(--bg-panel)); border-color: rgba(255,212,121,0.3); }
.quarter-grid .oracle-link .q-num { color: var(--gold); }

/* ============================================================
   Autor / E-E-A-T Byline
   ============================================================ */
.byline {
  display: flex; align-items: center; gap: 0.8rem; margin: 1.5rem 0;
  color: var(--muted); font-size: 0.92rem;
}
.byline .avatar {
  width: 44px; height: 44px; border-radius: 50%; flex: none;
  background: linear-gradient(140deg, var(--accent-deep), var(--accent-bright));
  display: grid; place-items: center; color: #fff; font-weight: 700; font-family: var(--font-display);
  box-shadow: 0 0 0 1px var(--line), 0 6px 18px -6px var(--accent-glow);
}
.byline a { color: var(--ink); }
.byline .updated { color: var(--muted); }

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  margin-top: 4rem; border-top: 1px solid var(--line);
  background: linear-gradient(180deg, transparent, rgba(4,6,15,0.6));
  padding-block: 2.5rem;
  font-size: 0.9rem; color: var(--muted);
}
.site-footer .cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1.5rem; }
.site-footer h4 { color: var(--ink-soft); font-family: var(--font-body); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.1em; }
.site-footer a { color: var(--ink-soft); text-decoration: none; display: block; padding: 0.15rem 0; }
.site-footer a:hover { color: var(--accent-bright); }
.site-footer .legal { margin-top: 1.5rem; padding-top: 1.5rem; border-top: 1px solid var(--line); }

/* Utility */
.visually-hidden {
  position: absolute !important; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}