/* afu.tools landing page.
   Palette matches the Funkpate app so the family looks like one thing.
   Dark is the default, light follows the system setting. */

:root {
  color-scheme: dark;
  --bg: #0a0e1f;
  --bg2: #151b35;
  --fg: #eef0fa;
  --muted: #8a93b3;
  --accent: #6aa6ff;
  --accent2: #a78bfa;
  --border: #2a3358;
  --card-bg: linear-gradient(180deg, rgba(28, 36, 68, 0.85), rgba(21, 27, 53, 0.85));
  --card-hover: rgba(106, 166, 255, 0.09);
  --header-bg: rgba(10, 14, 31, 0.72);
  --on-accent: #0a0e1f;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  --radius: 14px;
  --maxw: 1080px;
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

@media (prefers-color-scheme: light) {
  :root {
    color-scheme: light;
    --bg: #f4f6fb;
    --bg2: #ffffff;
    --fg: #1a2235;
    --muted: #5b6478;
    --accent: #2f6fed;
    --accent2: #7c5cff;
    --border: #d6dbe8;
    --card-bg: #ffffff;
    --card-hover: rgba(47, 111, 237, 0.06);
    --header-bg: rgba(255, 255, 255, 0.85);
    --on-accent: #ffffff;
    --shadow: 0 10px 30px rgba(20, 30, 60, 0.10);
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 84px; }
body {
  margin: 0;
  color: var(--fg);
  background:
    radial-gradient(1200px 600px at 8% -10%, rgba(106, 166, 255, 0.13), transparent 60%),
    radial-gradient(900px 500px at 105% 5%, rgba(167, 139, 250, 0.12), transparent 60%),
    var(--bg);
  background-attachment: fixed;
  line-height: 1.65;
  overflow-x: clip;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration-color: color-mix(in srgb, var(--accent) 45%, transparent); text-underline-offset: 3px; }
a:hover { text-decoration-color: currentColor; }

.wrap { width: min(100% - 2.5rem, var(--maxw)); margin-inline: auto; }
.muted { color: var(--muted); }
.small { font-size: 0.9rem; }

.skip {
  position: absolute; left: -9999px; top: 0;
  background: var(--bg2); color: var(--fg); padding: 0.6rem 1rem; z-index: 20;
}
.skip:focus { left: 1rem; top: 1rem; }

/* ------------------------------------------------------------------ Topbar */

.topbar {
  position: sticky; top: 0; z-index: 10;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.bar {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1.5rem; min-height: 62px; flex-wrap: wrap;
}
.brand {
  display: inline-flex; align-items: center; gap: 0.55rem;
  font-weight: 650; font-size: 1.05rem; letter-spacing: -0.01em;
  color: var(--fg); text-decoration: none;
}
.brand-dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 18%, transparent);
}
.topbar nav { display: flex; gap: 1.1rem; flex-wrap: wrap; }
.topbar nav a {
  color: var(--muted); text-decoration: none; font-size: 0.93rem; padding: 0.35rem 0;
  border-bottom: 2px solid transparent;
}
.topbar nav a:hover { color: var(--fg); border-bottom-color: var(--accent); }

/* -------------------------------------------------------------------- Hero */

.hero { padding: clamp(2.5rem, 7vw, 5.5rem) 0 clamp(1.5rem, 4vw, 3rem); }
.hero-grid {
  display: grid; gap: clamp(1.5rem, 4vw, 3rem);
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  align-items: center;
}
.kicker {
  margin: 0 0 0.6rem; text-transform: uppercase; letter-spacing: 0.14em;
  font-size: 0.75rem; font-weight: 600; color: var(--accent);
}
h1 {
  margin: 0 0 1rem; font-size: clamp(2rem, 5vw, 3.1rem); line-height: 1.1;
  letter-spacing: -0.02em; font-weight: 700;
  background: linear-gradient(90deg, var(--fg), color-mix(in srgb, var(--accent) 70%, var(--fg)));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.lead { margin: 0 0 0.9rem; font-size: clamp(1rem, 1.6vw, 1.12rem); color: color-mix(in srgb, var(--fg) 88%, var(--muted)); max-width: 60ch; }
.cta { display: flex; gap: 0.75rem; flex-wrap: wrap; margin-top: 1.6rem; }
.btn {
  display: inline-block; padding: 0.7rem 1.25rem; border-radius: 999px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: var(--on-accent); font-weight: 600; text-decoration: none;
  box-shadow: var(--shadow);
}
.btn:hover { filter: brightness(1.08); }
.btn.ghost {
  background: transparent; color: var(--fg);
  border: 1px solid var(--border); box-shadow: none;
}
.btn.ghost:hover { border-color: var(--accent); background: var(--card-hover); }
.hero-art svg { width: 100%; height: auto; max-height: 300px; display: block; }

/* ---------------------------------------------------------------- Sections */

.section { padding: clamp(2.2rem, 5vw, 3.6rem) 0; }
h2 {
  font-size: clamp(1.4rem, 2.6vw, 1.85rem); line-height: 1.2; letter-spacing: -0.015em;
  margin: 0 0 0.8rem; padding-left: 0.85rem;
  border-left: 3px solid transparent;
  border-image: linear-gradient(180deg, var(--accent), var(--accent2)) 1;
}
h3 { font-size: 1.12rem; margin: 2rem 0 0.4rem; letter-spacing: -0.01em; }
.section-intro { color: var(--muted); max-width: 62ch; margin: 0 0 1.8rem; }
.prose p { max-width: 68ch; }
.prose ul { max-width: 68ch; }

/* ------------------------------------------------------------------- Cards */

.cards {
  display: grid; gap: 1.1rem;
  grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
}
.card {
  display: flex; flex-direction: column;
  background: var(--card-bg);
  border: 1px solid var(--border); border-radius: var(--radius);
  padding: 1.4rem 1.4rem 1.2rem;
  color: var(--fg); text-decoration: none;
  transition: transform 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}
.card:hover { transform: translateY(-3px); border-color: var(--accent); box-shadow: var(--shadow); }
.card-head { display: flex; align-items: center; gap: 0.7rem; margin-bottom: 0.6rem; }
.card-head h3 { margin: 0; font-size: 1.22rem; }
.card .icon { font-size: 1.5rem; line-height: 1; }
.card p { margin: 0 0 0.8rem; color: color-mix(in srgb, var(--fg) 82%, var(--muted)); font-size: 0.96rem; }
.card-link {
  margin-top: auto; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.85rem; color: var(--accent);
}
.card-link::after { content: " →"; }

/* ------------------------------------------------------------------ Tabelle */

.table-scroll { overflow-x: auto; margin: 1.4rem 0 0.6rem; }
table.classes { border-collapse: collapse; width: 100%; min-width: 560px; font-size: 0.95rem; }
table.classes th, table.classes td {
  text-align: left; padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--border);
  vertical-align: top;
}
table.classes thead th { color: var(--muted); font-weight: 600; font-size: 0.82rem; text-transform: uppercase; letter-spacing: 0.06em; }
table.classes tbody th {
  font-size: 1.15rem; font-weight: 700; width: 4rem;
  color: transparent; background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text; background-clip: text;
}

.note {
  border-left: 3px solid color-mix(in srgb, var(--accent) 55%, transparent);
  background: var(--card-hover);
  padding: 0.75rem 1rem; border-radius: 0 8px 8px 0;
  color: var(--muted); font-size: 0.93rem; max-width: 68ch;
}

/* ------------------------------------------------------------------- Listen */

ul.plain { list-style: none; padding: 0; margin: 1rem 0; }
ul.plain li {
  padding: 0.7rem 0 0.7rem 1.4rem; border-bottom: 1px solid var(--border);
  position: relative;
}
ul.plain li::before {
  content: ""; position: absolute; left: 0; top: 1.35em;
  width: 8px; height: 8px; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
}

ul.linklist { list-style: none; padding: 0; margin: 0; }
ul.linklist li {
  display: flex; flex-wrap: wrap; gap: 0.2rem 1rem; align-items: baseline;
  padding: 0.75rem 0; border-bottom: 1px solid var(--border);
}
ul.linklist span { color: var(--muted); font-size: 0.92rem; }

/* ------------------------------------------------------------------ Footer */

.footer { border-top: 1px solid var(--border); margin-top: 3rem; padding: 2.5rem 0 3rem; background: color-mix(in srgb, var(--bg2) 45%, transparent); }
.footer-grid { display: grid; gap: 1.8rem; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.footer p { margin: 0 0 0.5rem; }
.footer .brand { font-size: 1rem; }
ul.footlinks { list-style: none; padding: 0; margin: 0; font-size: 0.9rem; }
ul.footlinks li { padding: 0.2rem 0; }

@media (max-width: 760px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-art { max-width: 260px; margin-inline: auto; }
  html { scroll-padding-top: 120px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .card:hover { transform: none; }
}

/* ---------------------------------------------------------- OV-Beitritt B37 */

.join {
  display: grid; gap: 1.4rem;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  align-items: center;
  margin: 1.8rem 0 1.2rem;
  padding: 1.5rem 1.6rem;
  border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--card-bg);
  box-shadow: var(--shadow);
  position: relative; overflow: hidden;
}
/* Farbkante links, damit der Kasten sich von den Fließtext-Blöcken absetzt. */
.join::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 4px;
  background: linear-gradient(180deg, var(--accent), var(--accent2));
}
.join h3 { margin: 0 0 0.5rem; font-size: 1.15rem; }
.join p { margin: 0; font-size: 0.96rem; color: color-mix(in srgb, var(--fg) 82%, var(--muted)); max-width: 60ch; }
.join-cta { display: flex; flex-direction: column; gap: 0.6rem; align-items: stretch; }
.join-cta .btn { text-align: center; }

@media (max-width: 760px) {
  .join { grid-template-columns: 1fr; }
}

/* ================================================================== Werkzeug-
   Seiten: Filterleisten, Datentabellen, Rechner. Alles, was nicht zur reinen
   Startseite gehoert, liegt ab hier.                                         */

.page-head { padding: clamp(2rem, 5vw, 3.2rem) 0 0.6rem; }
.page-head h1 { font-size: clamp(1.7rem, 4vw, 2.5rem); margin-bottom: 0.6rem; }
.page-head .lead { max-width: 70ch; }

.crumbs { font-size: 0.88rem; color: var(--muted); margin: 0 0 0.9rem; }
.crumbs a { color: var(--muted); }
.crumbs a:hover { color: var(--accent); }

/* -------------------------------------------------------------- Filterleiste */

.filters {
  display: flex; flex-wrap: wrap; gap: 0.8rem 1rem; align-items: flex-end;
  padding: 1.1rem 1.2rem; margin: 1.2rem 0;
  border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--card-bg);
}
.field { display: flex; flex-direction: column; gap: 0.3rem; min-width: 0; }
.field label { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.07em; color: var(--muted); font-weight: 600; }
.field input, .field select {
  background: var(--bg2); color: var(--fg);
  border: 1px solid var(--border); border-radius: 9px;
  padding: 0.5rem 0.7rem; font: inherit; font-size: 0.95rem;
  min-width: 8.5rem;
}
.field input:focus, .field select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.field.grow { flex: 1 1 14rem; }
.field.grow input { width: 100%; }
.field-hint { font-size: 0.78rem; color: var(--muted); }

button.btn, .btn-sm {
  font: inherit; cursor: pointer; border: 0;
}
.btn-sm {
  display: inline-block; padding: 0.45rem 0.9rem; border-radius: 999px;
  border: 1px solid var(--border); background: var(--bg2); color: var(--fg);
  text-decoration: none; font-size: 0.9rem;
}
.btn-sm:hover { border-color: var(--accent); background: var(--card-hover); }
.btn-sm[aria-pressed="true"] {
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: var(--on-accent); border-color: transparent; font-weight: 600;
}
.btn-row { display: flex; flex-wrap: wrap; gap: 0.5rem; align-items: center; }

/* ------------------------------------------------------------ Datentabellen */

.data-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: var(--radius); }
table.data { border-collapse: collapse; width: 100%; font-size: 0.93rem; }
table.data th, table.data td { padding: 0.55rem 0.8rem; text-align: left; border-bottom: 1px solid var(--border); white-space: nowrap; }
table.data th { position: sticky; top: 0; background: var(--bg2); color: var(--muted); font-size: 0.76rem; text-transform: uppercase; letter-spacing: 0.06em; z-index: 1; }
table.data tbody tr:hover { background: var(--card-hover); }
table.data td.wrap { white-space: normal; min-width: 14rem; }
table.data td.num, table.data th.num { text-align: right; font-variant-numeric: tabular-nums; }
table.data .mono { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
table.data tbody tr:last-child td { border-bottom: 0; }

.badge {
  display: inline-block; padding: 0.1rem 0.5rem; border-radius: 999px;
  font-size: 0.76rem; font-weight: 600; letter-spacing: 0.02em;
  border: 1px solid var(--border); color: var(--muted); background: var(--bg2);
}
.badge.ok { color: #10b981; border-color: color-mix(in srgb, #10b981 45%, transparent); background: color-mix(in srgb, #10b981 12%, transparent); }
.badge.busy { color: #f59e0b; border-color: color-mix(in srgb, #f59e0b 45%, transparent); background: color-mix(in srgb, #f59e0b 12%, transparent); }
.badge.no { color: #ef4444; border-color: color-mix(in srgb, #ef4444 45%, transparent); background: color-mix(in srgb, #ef4444 12%, transparent); }
.badge.a { color: var(--accent2); border-color: color-mix(in srgb, var(--accent2) 45%, transparent); }

.count-line { color: var(--muted); font-size: 0.9rem; margin: 1rem 0 0.5rem; }
.empty { padding: 2rem 1rem; text-align: center; color: var(--muted); }

/* ---------------------------------------------------------------- Bandplan */

.band-row { border: 1px solid var(--border); border-radius: var(--radius); background: var(--card-bg); margin-bottom: 0.7rem; overflow: hidden; }
.band-row > summary { cursor: pointer; padding: 0.85rem 1.1rem; display: flex; flex-wrap: wrap; gap: 0.6rem 1rem; align-items: center; }
.band-row > summary::-webkit-details-marker { display: none; }
.band-row > summary::before { content: "▸"; color: var(--accent); font-size: 0.9rem; }
.band-row[open] > summary::before { content: "▾"; }
.band-name { font-weight: 700; font-size: 1.05rem; min-width: 4.5rem; }
.band-range { color: var(--muted); font-size: 0.9rem; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
.band-body { padding: 0 1.1rem 1.1rem; }
.band-row.locked { opacity: 0.45; }
.pw { display: inline-flex; gap: 0.3rem; align-items: baseline; font-size: 0.86rem; }

.bar-scale { position: relative; height: 34px; margin: 0.8rem 0 0.4rem; border-radius: 8px; background: var(--bg2); border: 1px solid var(--border); overflow: hidden; }
.bar-seg { position: absolute; top: 0; bottom: 0; border-right: 1px solid var(--border); font-size: 0.68rem; color: var(--muted); padding: 0.2rem 0.25rem; overflow: hidden; }
.bar-seg.cw { background: color-mix(in srgb, var(--accent) 22%, transparent); }
.bar-seg.narrow { background: color-mix(in srgb, var(--accent2) 22%, transparent); }
.bar-seg.all { background: color-mix(in srgb, #10b981 16%, transparent); }

/* ---------------------------------------------------------------- Rechner */

.calc-grid { display: grid; gap: 1.1rem; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); }
.calc {
  border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--card-bg); padding: 1.2rem 1.3rem 1.3rem;
}
.calc h3 { margin: 0 0 0.3rem; font-size: 1.08rem; }
.calc p.hint { margin: 0 0 0.9rem; font-size: 0.88rem; color: var(--muted); }
.calc .inputs { display: grid; gap: 0.7rem; grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr)); }
.calc .out {
  margin-top: 1rem; padding: 0.85rem 1rem; border-radius: 10px;
  background: var(--bg2); border: 1px solid var(--border);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.94rem; white-space: pre-wrap; line-height: 1.7;
}
.calc .out strong { font-family: inherit; color: var(--accent); }

/* ------------------------------------------------------------------ Lexikon */

.lex-grid { display: grid; gap: 0.6rem; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }
.lex-item { border: 1px solid var(--border); border-radius: 10px; padding: 0.6rem 0.85rem; background: var(--card-bg); }
.lex-item dt { font-weight: 700; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; color: var(--accent); }
.lex-item dd { margin: 0.15rem 0 0; font-size: 0.92rem; color: color-mix(in srgb, var(--fg) 85%, var(--muted)); }
.jump { display: flex; flex-wrap: wrap; gap: 0.3rem; margin: 0.8rem 0 1.4rem; }
.jump a { font-family: ui-monospace, monospace; font-size: 0.85rem; padding: 0.2rem 0.5rem; border: 1px solid var(--border); border-radius: 7px; text-decoration: none; }

/* --------------------------------------------------------------------- Code */

pre.code {
  background: var(--bg2); border: 1px solid var(--border); border-radius: 10px;
  padding: 0.9rem 1rem; overflow-x: auto; font-size: 0.86rem; line-height: 1.6;
}
code.inline { background: var(--bg2); border: 1px solid var(--border); border-radius: 6px; padding: 0.05rem 0.35rem; font-size: 0.88em; }

/* ------------------------------------------------------------------ Artikel */

.article { max-width: 72ch; }
.article h2 { margin-top: 2.4rem; }
.article h3 { margin-top: 1.8rem; }
.article figure { margin: 1.6rem 0; }
.article table { border-collapse: collapse; width: 100%; font-size: 0.93rem; margin: 1.2rem 0; }
.article th, .article td { text-align: left; padding: 0.55rem 0.8rem; border-bottom: 1px solid var(--border); vertical-align: top; }
.article th { color: var(--muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.05em; }

.toolnav { display: flex; flex-wrap: wrap; gap: 0.4rem; margin: 0 0 1.6rem; }
.toolnav a {
  font-size: 0.88rem; padding: 0.35rem 0.75rem; border-radius: 999px;
  border: 1px solid var(--border); text-decoration: none; color: var(--muted);
}
.toolnav a:hover { border-color: var(--accent); color: var(--fg); }
.toolnav a[aria-current="page"] { background: var(--card-hover); color: var(--fg); border-color: var(--accent); }

.source-line { font-size: 0.85rem; color: var(--muted); margin-top: 1.2rem; }
.spinner { display: inline-block; width: 14px; height: 14px; border: 2px solid var(--border); border-top-color: var(--accent); border-radius: 50%; animation: spin 0.8s linear infinite; vertical-align: -2px; }
@keyframes spin { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) { .spinner { animation: none; } }