/* ==========================================================
   Lernplattform Physik & Maschinenbau – gemeinsames Stylesheet
   Funktioniert offline (keine externen Schriften/Bibliotheken)
   ========================================================== */

:root {
  --bg: #f5f6f8;
  --surface: #ffffff;
  --surface-2: #f0f3f7;
  --text: #1c2430;
  --text-2: #4f5b6b;
  --line: #dde3ea;
  --primary: #1f5fae;        /* Physik-Blau */
  --primary-soft: #e6effa;
  --mb: #b4541a;             /* Maschinenbau-Orange */
  --mb-soft: #fbeee4;
  --tip: #9a6a00;
  --tip-soft: #fff6dc;
  --ok: #1e7b45;
  --ok-soft: #e4f4ea;
  --bad: #b3261e;
  --bad-soft: #fbe7e5;
  --merk: #1f5fae;
  --radius: 10px;
  --shadow: 0 1px 2px rgba(20, 30, 50, .06), 0 2px 8px rgba(20, 30, 50, .05);
  --font: "Segoe UI", system-ui, -apple-system, Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-math: "Cambria Math", Cambria, "Times New Roman", "STIX Two Math", serif;
  --sidebar-w: 270px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.6;
}
img { max-width: 100%; height: auto; }
a { color: var(--primary); }
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 .5em; }
h1 { font-size: 1.9rem; }
h2 { font-size: 1.45rem; }
h3 { font-size: 1.15rem; }
p { margin: 0 0 .8em; }

/* ---------- Kopfzeile ---------- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
  display: flex; align-items: center; gap: 16px;
  padding: 10px 20px; min-height: 58px;
}
.brand { font-weight: 700; color: var(--text); text-decoration: none; display: flex; align-items: center; gap: 10px; white-space: nowrap; }
.brand-logo { width: 30px; height: 30px; border-radius: 8px; background: var(--primary); color: #fff; display: grid; place-items: center; font-size: 15px; font-weight: 700; }
.crumbs { font-size: .9rem; color: var(--text-2); overflow: hidden; white-space: nowrap; text-overflow: ellipsis; }
.crumbs a { color: var(--text-2); text-decoration: none; }
.crumbs a:hover { color: var(--primary); text-decoration: underline; }
.crumbs span.sep { margin: 0 6px; opacity: .6; }
.topbar .spacer { flex: 1; }
.menu-btn { display: none; border: 1px solid var(--line); background: var(--surface); border-radius: 8px; padding: 6px 10px; font: inherit; cursor: pointer; }

/* ---------- Startseite / Übersichten ---------- */
.wrap { max-width: 1080px; margin: 0 auto; padding: 32px 20px 64px; }
.hero { margin: 8px 0 28px; }
.hero p { color: var(--text-2); max-width: 60ch; font-size: 1.05rem; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 18px; }
.card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 22px; text-decoration: none; color: inherit; display: block;
  transition: transform .12s ease, border-color .12s ease;
}
a.card:hover { transform: translateY(-2px); border-color: var(--primary); }
.card h2 { margin-bottom: .3em; }
.card p { color: var(--text-2); margin: 0; }
.card .tag { display: inline-block; font-size: .75rem; font-weight: 600; letter-spacing: .03em; text-transform: uppercase; padding: 2px 8px; border-radius: 99px; margin-bottom: 10px; }
.tag.physik { background: var(--primary-soft); color: var(--primary); }
.tag.mb { background: var(--mb-soft); color: var(--mb); }
.tag.bald { background: var(--surface-2); color: var(--text-2); }
.card.disabled { opacity: .65; }

.kapitel { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); margin-bottom: 14px; box-shadow: var(--shadow); overflow: hidden; }
.kapitel > summary { cursor: pointer; padding: 14px 18px; font-weight: 600; list-style: none; display: flex; align-items: center; gap: 10px; }
.kapitel > summary::-webkit-details-marker { display: none; }
.kapitel > summary::before { content: "▸"; color: var(--text-2); transition: transform .15s; }
.kapitel[open] > summary::before { transform: rotate(90deg); }
.kapitel .teil-label { margin-left: auto; font-size: .8rem; color: var(--text-2); font-weight: 400; }
.themen { list-style: none; margin: 0; padding: 0 18px 12px 40px; }
.themen li { padding: 7px 0; border-top: 1px solid var(--line); display: flex; align-items: center; gap: 10px; }
.themen li a { font-weight: 600; }
.themen li .status { margin-left: auto; font-size: .8rem; color: var(--text-2); }
.themen li.bald { color: var(--text-2); }
.pill { font-size: .72rem; padding: 1px 8px; border-radius: 99px; background: var(--surface-2); color: var(--text-2); }
.pill.neu { background: var(--ok-soft); color: var(--ok); font-weight: 600; }
.mini-progress { width: 90px; height: 6px; background: var(--surface-2); border-radius: 99px; overflow: hidden; display: inline-block; vertical-align: middle; }
.mini-progress > span { display: block; height: 100%; background: var(--ok); width: 0; }

/* ---------- Lernseite: Layout mit Seitenleiste ---------- */
.layout { display: grid; grid-template-columns: var(--sidebar-w) minmax(0, 1fr); max-width: 1320px; margin: 0 auto; }
.sidebar {
  position: sticky; top: 58px; align-self: start; height: calc(100vh - 58px); overflow-y: auto;
  padding: 22px 14px 40px 20px; border-right: 1px solid var(--line); font-size: .93rem;
}
.sidebar h4 { font-size: .75rem; text-transform: uppercase; letter-spacing: .06em; color: var(--text-2); margin: 18px 0 6px; }
.sidebar ol, .sidebar ul { list-style: none; margin: 0; padding: 0; }
.sidebar a { display: block; padding: 5px 10px; border-radius: 7px; color: var(--text); text-decoration: none; }
.sidebar a:hover { background: var(--surface-2); }
.sidebar a.active { background: var(--primary-soft); color: var(--primary); font-weight: 600; }
.sidebar .sub a { padding-left: 24px; font-size: .88rem; color: var(--text-2); }
.sidebar .sub a.active { color: var(--primary); }
.progress-box { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 12px; margin-bottom: 8px; }
.progress-box .bar { height: 8px; background: var(--surface-2); border-radius: 99px; overflow: hidden; margin: 6px 0 4px; }
.progress-box .bar span { display: block; height: 100%; width: 0; background: var(--ok); transition: width .3s; }
.progress-box small { color: var(--text-2); }
.linkbtn { background: none; border: 0; padding: 0; color: var(--text-2); font: inherit; font-size: .8rem; text-decoration: underline; cursor: pointer; }

main.content { padding: 28px 36px 80px; min-width: 0; }
.page-head { margin-bottom: 26px; }
.page-head p.lead { color: var(--text-2); font-size: 1.05rem; max-width: 70ch; }
.quelle { font-size: .85rem; color: var(--text-2); }

/* Lerneinheit */
.einheit { margin: 0 0 56px; }
.einheit-kopf { display: flex; align-items: baseline; gap: 12px; border-bottom: 2px solid var(--primary); padding-bottom: 8px; margin-bottom: 18px; }
.einheit-kopf .nr { font-size: .8rem; font-weight: 700; color: #fff; background: var(--primary); border-radius: 6px; padding: 2px 8px; white-space: nowrap; }
.einheit-kopf h2 { margin: 0; }

.block-label { display: inline-flex; align-items: center; gap: 8px; font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; color: var(--text-2); margin: 10px 0 10px; }
.block-label::before { content: ""; width: 18px; height: 3px; background: currentColor; border-radius: 2px; }

/* Input-Karte (Skript) */
.input {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 26px; box-shadow: var(--shadow); margin-bottom: 26px;
}
.input h3 { color: var(--primary); margin-top: 1.2em; }
.input h3:first-child { margin-top: 0; }
.merke {
  border-left: 4px solid var(--merk); background: var(--primary-soft);
  padding: 12px 16px; border-radius: 0 8px 8px 0; margin: 14px 0;
}
.merke strong.titel { display: block; font-size: .78rem; text-transform: uppercase; letter-spacing: .06em; color: var(--primary); margin-bottom: 4px; }
.beispiel { background: var(--surface-2); border-radius: 8px; padding: 12px 16px; margin: 14px 0; }
.beispiel strong.titel { display: block; font-size: .78rem; text-transform: uppercase; letter-spacing: .06em; color: var(--text-2); margin-bottom: 4px; }
.zweispaltig { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: 24px; align-items: start; }
figure { margin: 12px 0; }
figure img, figure svg { display: block; background: #fff; border: 1px solid var(--line); border-radius: 8px; }
figcaption { font-size: .85rem; color: var(--text-2); margin-top: 6px; }

/* Formeln (ohne externe Bibliothek) */
.m { font-family: var(--font-math); font-style: italic; white-space: nowrap; }
.m .up, .m .n { font-style: normal; }
.formel {
  display: flex; align-items: center; justify-content: center; gap: 14px; flex-wrap: wrap;
  font-family: var(--font-math); font-size: 1.3rem; margin: 14px 0; padding: 12px;
  background: var(--surface); border: 1px solid var(--line); border-radius: 8px; position: relative;
}
.formel .nr { position: absolute; right: 12px; font-size: .85rem; color: var(--text-2); font-family: var(--font); }
.formel i, .m i { font-style: italic; }
.frac { display: inline-flex; flex-direction: column; align-items: center; vertical-align: middle; line-height: 1.15; margin: 0 2px; }
.frac > span { padding: 0 3px; }
.frac > span:first-child { border-bottom: 1.5px solid currentColor; }
.bar-over { text-decoration: overline; }
sub, sup { line-height: 0; }

/* ---------- Aufgaben ---------- */
.aufgabe {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); margin-bottom: 20px; overflow: hidden;
}
.aufgabe-kopf { display: flex; align-items: center; gap: 12px; padding: 14px 20px; border-bottom: 1px solid var(--line); background: #fbfcfd; }
.aufgabe-kopf h3 { margin: 0; font-size: 1.08rem; }
.aufgabe-kopf .nr { font-family: ui-monospace, Consolas, monospace; font-size: .85rem; color: var(--text-2); }
.aufgabe-kopf .level { margin-left: auto; font-size: .75rem; color: var(--text-2); white-space: nowrap; }
.aufgabe-kopf .done { font-size: .8rem; font-weight: 600; color: var(--ok); white-space: nowrap; }
.aufgabe-body { padding: 16px 20px 6px; }
.aufgabe-body > p:first-child { margin-top: 0; }
.zusatz-kopf { font-weight: 700; margin: 14px 0 6px; color: var(--mb); }

.teil { border-top: 1px dashed var(--line); padding: 14px 0 12px; }
.aufgabe-body > .teil:first-of-type { border-top: 0; }
.teil .frage { margin-bottom: 8px; }
.teil .frage b.lbl { color: var(--primary); margin-right: 4px; }
.teil[data-state="ok"] .frage b.lbl::after { content: " ✓"; color: var(--ok); }

.eingaben { display: flex; flex-wrap: wrap; gap: 10px 18px; align-items: center; margin: 6px 0 10px; }
.feld { display: inline-flex; align-items: center; gap: 6px; }
.feld label { font-family: var(--font); font-style: normal; white-space: nowrap; }
.feld label i { font-family: var(--font-math); font-style: italic; font-size: 1.08em; }
.feld input, .feld select {
  font: inherit; font-size: 1rem; padding: 6px 9px; border: 1.5px solid var(--line); border-radius: 7px;
  width: 8.5em; background: #fff; color: var(--text);
}
.feld select { width: auto; min-width: 8em; }
.feld input:focus, .feld select:focus { outline: 2px solid var(--primary-soft); border-color: var(--primary); }
.feld .unit { color: var(--text-2); font-size: .95rem; white-space: nowrap; }
.feld.ok input, .feld.ok select { border-color: var(--ok); background: var(--ok-soft); }
.feld.bad input, .feld.bad select { border-color: var(--bad); background: var(--bad-soft); }

.aktionen { display: flex; flex-wrap: wrap; gap: 8px; margin: 6px 0 4px; }
.btn {
  font: inherit; font-size: .9rem; font-weight: 600; border-radius: 7px; padding: 6px 13px; cursor: pointer;
  border: 1.5px solid var(--line); background: var(--surface); color: var(--text);
}
.btn:hover { border-color: var(--text-2); }
.btn.primary { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn.primary:hover { filter: brightness(1.08); }
.btn.tip { border-color: #e8cf8a; background: var(--tip-soft); color: var(--tip); }
.btn.loes { border-color: var(--line); }
.btn[disabled] { opacity: .5; cursor: default; }
.btn.self-ok { border-color: var(--ok); color: var(--ok); }
.btn.self-no { border-color: var(--bad); color: var(--bad); }

.feedback { margin: 8px 0 2px; padding: 8px 12px; border-radius: 7px; font-size: .95rem; display: none; }
.feedback.show { display: block; }
.feedback.ok { background: var(--ok-soft); color: var(--ok); }
.feedback.bad { background: var(--bad-soft); color: var(--bad); }
.feedback.info { background: var(--surface-2); color: var(--text-2); }

.tipp { display: none; background: var(--tip-soft); border-left: 4px solid #e2b93b; padding: 9px 14px; border-radius: 0 7px 7px 0; margin: 8px 0; font-size: .96rem; }
.tipp.show { display: block; }
.tipp::before { content: attr(data-label); display: block; font-size: .75rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: var(--tip); margin-bottom: 2px; }
.loesung { display: none; background: var(--ok-soft); border-left: 4px solid var(--ok); padding: 10px 16px; border-radius: 0 7px 7px 0; margin: 8px 0; }
.loesung.show { display: block; }
.loesung::before { content: "Musterlösung"; display: block; font-size: .75rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: var(--ok); margin-bottom: 4px; }
.loesung .formel { background: #fff; font-size: 1.15rem; justify-content: flex-start; }
.rechnung { font-family: var(--font-math); font-size: 1.1rem; line-height: 2.2; }
.self-check { display: none; align-items: center; gap: 8px; flex-wrap: wrap; font-size: .9rem; color: var(--text-2); margin-top: 6px; }
.self-check.show { display: flex; }

table.werte { border-collapse: collapse; font-size: .88rem; margin: 10px 0; width: 100%; display: block; overflow-x: auto; }
table.werte th, table.werte td { border: 1px solid var(--line); padding: 4px 8px; text-align: center; white-space: nowrap; }
table.werte th { background: var(--surface-2); text-align: left; }

.hinweis { font-size: .92rem; color: var(--text-2); background: var(--surface-2); border-radius: 7px; padding: 8px 12px; margin: 8px 0; }
.papier { font-size: .9rem; color: var(--text-2); display: flex; gap: 8px; align-items: flex-start; }
.papier::before { content: "✎"; font-size: 1.05rem; }

/* ---------- Interaktive Bausteine ---------- */
.widget { background: var(--surface-2); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; margin: 16px 0; }
.widget h4 { margin: 0 0 8px; font-size: 1rem; }
.widget .regler { display: grid; grid-template-columns: auto 1fr auto; gap: 6px 12px; align-items: center; margin: 10px 0; font-size: .95rem; }
.widget input[type=range] { width: 100%; accent-color: var(--primary); }
.widget output { font-variant-numeric: tabular-nums; font-weight: 600; min-width: 6.5em; text-align: right; }
.widget svg { width: 100%; height: auto; background: #fff; border: 1px solid var(--line); border-radius: 8px; display: block; }
.widget .ergebnis { font-size: 1rem; margin-top: 8px; }
.umrechner { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; }
.umrechner input { font: inherit; width: 7em; padding: 6px 8px; border: 1.5px solid var(--line); border-radius: 7px; }

.chart text { font-family: var(--font); font-size: 12px; fill: #333; }
.chart .grid { stroke: #e3e7ec; }
.chart .grid.major { stroke: #c9d1da; }
.chart .axis { stroke: #333; stroke-width: 1.4; }

.fusszeile { border-top: 1px solid var(--line); margin-top: 40px; padding-top: 16px; font-size: .85rem; color: var(--text-2); }
.nav-unten { display: flex; justify-content: space-between; gap: 12px; margin-top: 30px; }

/* ---------- Responsiv ---------- */
@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; }
  .menu-btn { display: inline-block; }
  .sidebar {
    position: fixed; left: 0; top: 58px; width: min(86vw, 320px); z-index: 40; background: var(--bg);
    transform: translateX(-102%); transition: transform .2s; box-shadow: 4px 0 20px rgba(0,0,0,.1);
  }
  body.nav-open .sidebar { transform: none; }
  main.content { padding: 20px 16px 60px; }
  .zweispaltig { grid-template-columns: 1fr; }
  .input { padding: 18px 16px; }
  .aufgabe-body { padding: 14px 14px 4px; }
  .crumbs { display: none; }
}

@media print {
  .topbar, .sidebar, .aktionen, .self-check, .widget { display: none !important; }
  .layout { display: block; }
  .tipp, .loesung { display: block !important; }
  body { background: #fff; }
}

/* Umbruch-Schutz für schmale Bildschirme */
.feld { flex-wrap: wrap; max-width: 100%; }
.feld select { max-width: 100%; }
.einheit-kopf { flex-wrap: wrap; }
h1, h2, h3 { hyphens: auto; -webkit-hyphens: auto; overflow-wrap: break-word; }
@media (max-width: 520px) {
  .feld select { min-width: 0; width: 100%; }
  .feld { width: 100%; }
  .feld input { flex: 1; min-width: 6em; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

/* ===== Mehrseitige Struktur: Aufgabenlisten, Navigation, Themen-Hub ===== */
.aufgabenliste { list-style: none; margin: 0; padding: 0; }
.aufgabenliste li a { display: flex; align-items: center; gap: 8px; }
.aufgabenliste .nr { font-family: ui-monospace, Consolas, monospace; font-size: .8rem; color: var(--text-2); min-width: 3.4em; }
.aufgabenliste .titel { flex: 1; }
.aufgabenliste .status-txt, .task-card .status-txt { font-size: .75rem; color: var(--text-2); white-space: nowrap; }
.fertig .status-txt { color: var(--ok); font-weight: 700; }
.sidebar .input-link { font-weight: 600; color: var(--primary); }
.sidebar .input-link.active { background: var(--primary-soft); }
.sidebar .le-titel { font-weight: 700; font-size: .95rem; margin: 14px 0 4px; }

.kontext { font-size: .85rem; color: var(--text-2); margin-bottom: 10px; display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.kontext a { color: var(--text-2); }
.nav-unten { display: grid; grid-template-columns: 1fr auto 1fr; gap: 10px; align-items: stretch; margin-top: 26px; }
.nav-unten a { text-decoration: none; }
.nav-karte { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 10px 14px; color: var(--text); display: block; }
.nav-karte:hover { border-color: var(--primary); }
.nav-karte small { display: block; color: var(--text-2); font-size: .78rem; }
.nav-karte.next { text-align: right; }
.nav-karte.mitte { display: flex; align-items: center; justify-content: center; font-size: .9rem; }
.nav-karte.leer { visibility: hidden; }

.le-karte { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 20px 22px; margin-bottom: 20px; }
.le-karte-kopf { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin-bottom: 6px; }
.le-karte-kopf .nr { font-size: .78rem; font-weight: 700; color: #fff; background: var(--primary); border-radius: 6px; padding: 2px 8px; }
.le-karte-kopf h2 { margin: 0; font-size: 1.25rem; flex: 1; }
.le-karte p { color: var(--text-2); margin-bottom: 12px; }
.input-btn { display: inline-flex; align-items: center; gap: 8px; text-decoration: none; background: var(--primary-soft); color: var(--primary); font-weight: 600; border-radius: 8px; padding: 8px 14px; margin-bottom: 14px; }
.input-btn:hover { filter: brightness(.97); }
.task-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(235px, 1fr)); gap: 8px; }
.task-card { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); border: 1px solid var(--line); border-radius: 8px; padding: 8px 12px; background: #fbfcfd; }
.task-card:hover { border-color: var(--primary); background: #fff; }
.task-card .nr { font-family: ui-monospace, Consolas, monospace; font-size: .8rem; color: var(--text-2); }
.task-card .titel { flex: 1; font-weight: 600; font-size: .93rem; line-height: 1.3; }
.task-card.fertig { border-color: #b7dcc5; background: var(--ok-soft); }
.gesamt-box { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 12px 16px; margin: 0 0 22px; }
.gesamt-box .bar { flex: 1; min-width: 160px; height: 10px; background: var(--surface-2); border-radius: 99px; overflow: hidden; }
.gesamt-box .bar span { display: block; height: 100%; width: 0; background: var(--ok); }
.start-btn { display: inline-block; margin-top: 18px; }
@media (max-width: 600px) {
  .nav-unten { grid-template-columns: 1fr 1fr; }
  .nav-karte.mitte { grid-column: 1 / -1; order: 3; }
}
.task-card .titel, .aufgabenliste .titel { min-width: 0; overflow-wrap: anywhere; hyphens: auto; -webkit-hyphens: auto; }
.task-card .status-txt, .aufgabenliste .status-txt { flex-shrink: 0; }
@media (max-width: 600px) {
  .aufgabe-body > div[style*="grid-template-columns"] { display: block !important; }
  .aufgabe-body > div[style*="grid-template-columns"] img { max-width: 160px; }
  .aufgabe-body > div[style*="grid-template-columns"] figure { margin-bottom: 12px !important; }
}

/* ===== Fortlaufende Aufgaben-Nummerierung ===== */
.task-card .kopf { display: flex; flex-direction: column; flex: 1; min-width: 0; gap: 1px; }
.task-card .kopf .nr { font-family: var(--font); font-size: .7rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: var(--primary); }
.task-card.fertig .kopf .nr { color: var(--ok); }
.aufgabenliste .nr { font-family: var(--font); min-width: 0; width: 1.7em; height: 1.7em; flex-shrink: 0; border-radius: 50%; background: var(--surface-2); color: var(--text-2); font-size: .75rem; font-weight: 700; display: inline-grid; place-items: center; }
.aufgabenliste a.active .nr { background: var(--primary); color: #fff; }
.aufgabenliste a.fertig .nr { background: var(--ok); color: #fff; }
.aufgabe-kopf .nr { font-family: var(--font); font-size: .75rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: #fff; background: var(--primary); border-radius: 6px; padding: 2px 8px; white-space: nowrap; }
.formel { padding-left: 3.2em; padding-right: 3.2em; }
/* Formeln als Fließtext setzen (kein Flex-Abstand zwischen Zeichen) */
.formel { display: block; text-align: center; line-height: 2.1; }
.formel .nr { top: 50%; transform: translateY(-50%); }
.loesung .formel { text-align: left; }
.aufgabenliste .nr { width: auto; min-width: 2.4em; height: 1.6em; border-radius: 99px; padding: 0 6px; }
@media (max-width: 700px) {
  table.werte { display: block !important; overflow-x: auto; max-width: 100%; }
  .widget .regler { grid-template-columns: 1fr auto; }
  .widget .regler input[type=range] { grid-column: 1 / -1; order: 0; }
}
@media (max-width: 700px) { .m { white-space: normal; } }
.nav-unten > * { min-width: 0; }
.nav-karte { overflow-wrap: anywhere; hyphens: auto; -webkit-hyphens: auto; }
.aufgabe-kopf { flex-wrap: wrap; }
.aufgabe-kopf h3 { min-width: 0; overflow-wrap: anywhere; }
/* Stoppuhren (Boot im Fluss) */
.stoppuhren { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; margin: 10px 0 4px; }
.uhr { background: var(--surface); border: 2px solid var(--line); border-radius: 10px; padding: 8px 12px; display: flex; flex-direction: column; align-items: center; text-align: center; }
.uhr-titel { font-size: .85rem; font-weight: 600; color: var(--text-2); }
.uhr-zeit { font-family: ui-monospace, Consolas, "Courier New", monospace; font-size: 1.7rem; font-weight: 700; font-variant-numeric: tabular-nums; line-height: 1.3; }
.uhr-status { font-size: .75rem; color: var(--text-2); }
.uhr.laeuft { border-color: var(--primary); }
.uhr.laeuft .uhr-status { color: var(--primary); font-weight: 600; }
.uhr.gestoppt { border-color: var(--ok); background: var(--ok-soft); }
.uhr.gestoppt .uhr-status { color: var(--ok); font-weight: 600; }
.uhr.fehler { border-color: var(--bad); background: var(--bad-soft); }
.uhr.gesamt .uhr-titel { color: var(--text); }
@media (max-width: 520px) { .stoppuhren { grid-template-columns: 1fr 1fr; } .uhr.gesamt { grid-column: 1 / -1; } .uhr-zeit { font-size: 1.35rem; } }
/* Kapitel-Navigation in der Seitenleiste */
.kapitel-nav { list-style: none; margin: 0; padding: 0; }
.kapitel-nav .thema { margin: 2px 0; }
.kapitel-nav .thema-link { display: flex; align-items: center; gap: 8px; font-weight: 700; }
.kapitel-nav .thema-link .titel, .kapitel-nav .le-liste .titel { flex: 1; min-width: 0; }
.kapitel-nav .thema.bald { color: var(--text-2); padding: 5px 10px; font-size: .9rem; display: flex; align-items: center; gap: 6px; }
.kapitel-nav .le-liste { list-style: none; margin: 2px 0 8px; padding: 0 0 0 10px; border-left: 2px solid var(--line); }
.kapitel-nav .le-liste a { display: flex; align-items: flex-start; gap: 8px; font-size: .88rem; }
.kapitel-nav .le-liste .nr { flex-shrink: 0; width: 1.6em; height: 1.6em; border-radius: 50%; background: var(--surface-2); color: var(--text-2); font-size: .72rem; font-weight: 700; display: inline-grid; place-items: center; margin-top: 1px; }
.kapitel-nav .le-liste a.active .nr { background: var(--primary); color: #fff; }
.kapitel-nav .le-liste a.fertig .nr { background: var(--ok); color: #fff; }
.kapitel-nav .status-txt { font-size: .72rem; color: var(--text-2); white-space: nowrap; flex-shrink: 0; }
.le-karte { scroll-margin-top: 76px; }
.kapitel-nav .titel, .aufgabenliste .titel, .sidebar .le-titel { overflow-wrap: anywhere; hyphens: auto; -webkit-hyphens: auto; }
.sidebar a { min-width: 0; }
/* Tabellen: nie breiter als der Inhaltsbereich */
table.werte { display: block !important; overflow-x: auto; max-width: 100%; }
table.werte th, table.werte td { white-space: normal; }
.einheit-kopf h2, .le-karte-kopf h2, .page-head h1 { min-width: 0; overflow-wrap: anywhere; }
main.content, .wrap { overflow-wrap: break-word; hyphens: auto; -webkit-hyphens: auto; }
/* Zug-Simulation (Aufgabe 4.3) */
.zsim h4 { font-size: 1.15rem; margin: 0 0 2px; }
.zsim h5 { font-size: 1rem; margin: 0 0 8px; }
.zsim .z-sub { color: #6b7385; margin: 0 0 12px; font-size: .93rem; }
.zsim .z-card { background: #fff; border: 1px solid #d9dee8; border-radius: 12px; padding: 12px; margin-bottom: 12px; }
.zsim .z-controls { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
.zsim .z-seg { display: inline-flex; border: 1px solid #d9dee8; border-radius: 8px; overflow: hidden; }
.zsim .z-seg button { border: 0; border-radius: 0; }
.zsim button, .zsim select { font: inherit; font-size: .93rem; padding: 7px 12px; border-radius: 8px; border: 1px solid #d9dee8; background: #fff; color: #1d2330; cursor: pointer; }
.zsim button.on { background: #2563eb; color: #fff; }
.zsim button.z-primary { background: #2563eb; color: #fff; border-color: #2563eb; min-width: 110px; }
.zsim .z-bglabel { display: flex; align-items: center; gap: 6px; cursor: pointer; font-size: .93rem; }
.zsim .z-bglabel input { accent-color: #2563eb; width: 18px; height: 18px; }
.zsim .z-slider { display: flex; align-items: center; gap: 10px; flex: 1; min-width: 220px; }
.zsim .z-slider input[type=range] { flex: 1; accent-color: #2563eb; }
.zsim .z-tval { font-variant-numeric: tabular-nums; min-width: 80px; font-weight: 600; }
.zsim canvas { width: 100%; display: block; border-radius: 8px; }
.zsim .z-track { height: 250px; }
.zsim .z-diag { height: 400px; }
.zsim .z-grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.zsim .z-eq { font-family: "Cambria Math", Cambria, Georgia, serif; font-size: 1.05rem; margin: 4px 0; }
.zsim .z1 { color: #2e9e3e; font-weight: 700; } .zsim .z2 { color: #e03131; font-weight: 700; }
.zsim .z-tab { border-collapse: collapse; width: 100%; font-variant-numeric: tabular-nums; }
.zsim .z-tab td { padding: 4px 6px; border-bottom: 1px solid #d9dee8; }
.zsim .z-tab td:last-child { text-align: right; font-weight: 600; white-space: nowrap; }
.zsim details summary { cursor: pointer; font-weight: 600; }
.zsim .z-hint { color: #6b7385; font-size: .88rem; margin-top: 6px; }
@media (max-width: 700px) { .zsim .z-grid2 { grid-template-columns: 1fr; } .zsim .z-track { height: 220px; } .zsim .z-diag { height: 320px; } }

/* ---------- Fußzeile mit Impressum & Rechtstexte ---------- */
.site-foot { border-top: 1px solid var(--line); padding: 18px 20px 28px; text-align: center; font-size: .85rem; color: var(--text-2); }
.site-foot a { color: var(--text-2); }
.rechtstext { max-width: 760px; }
.rechtstext h2 { font-size: 1.1rem; margin: 28px 0 6px; }
.rechtstext p, .rechtstext li { overflow-wrap: anywhere; }
.platzhalter { background: #fff3b0; color: #6b4e00; padding: 0 4px; border-radius: 4px; }

/* ---------- Punkte & Note ---------- */
.punkte-chip { align-self: center; margin-left: auto; font-size: .8rem; color: var(--text-2); background: var(--surface-2); border-radius: 99px; padding: 2px 10px; white-space: nowrap; cursor: help; }
.punkte-chip.fest { background: var(--ok-soft); color: var(--ok); font-weight: 600; }
.punkte-chip.fest.null { background: var(--bad-soft); color: var(--bad); }
.feedback .pkt { font-weight: 700; margin-left: 4px; white-space: nowrap; }
.note-txt { font-size: .85rem; font-weight: 600; color: var(--text); }
.progress-box .note-txt { margin-top: 4px; }
.progress-box .note-txt:empty { display: none; }
.gesamt-box .note-txt:not(:empty) { background: var(--surface-2); border-radius: 99px; padding: 2px 10px; }
.note-txt.kurz { font-weight: 400; color: var(--text-2); font-size: .8rem; }
.punkte-regeln { margin-top: 10px; font-size: .92rem; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 8px 14px; }
.punkte-regeln summary { cursor: pointer; font-weight: 600; }
.punkte-regeln ul { margin: 8px 0; padding-left: 20px; }
.notenschluessel { border-collapse: collapse; font-size: .85rem; margin: 6px 0 4px; display: block; overflow-x: auto; }
.notenschluessel th, .notenschluessel td { border: 1px solid var(--line); padding: 3px 8px; text-align: center; white-space: nowrap; }
.notenschluessel th { text-align: left; background: var(--surface-2); }
@media (max-width: 520px) { .punkte-chip { margin-left: 0; } }

/* ---------- Teilaufgaben: Eingabe & Buttons einklappbar ---------- */
.teil-leiste { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 4px 0 2px; }
.btn.aufklappen { background: var(--surface); border-color: var(--line); color: var(--primary); font-size: .9rem; padding-top: 5px; padding-bottom: 5px; }
.btn.aufklappen:hover { border-color: var(--primary); background: var(--primary-soft); }
.btn.aufklappen .pfeil { font-size: .8em; margin-left: 2px; }
.teil.zu > .eingaben, .teil.zu > .aktionen, .teil.zu > .feedback, .teil.zu > .tipp,
.teil.zu > .loesung, .teil.zu > .self-check { display: none !important; }
.teil:not(.zu) > .teil-leiste { margin-bottom: 6px; }
@media print { .teil-leiste { display: none !important; } .teil.zu > .tipp, .teil.zu > .loesung { display: block !important; } }
.site-foot .foot-hinweis { display: block; margin-top: 6px; font-size: .8rem; }

/* ---------- Thema 1.2 Beschleunigung ---------- */
.tachos { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, .8fr) minmax(0, 1fr); gap: 10px; align-items: center; margin: 10px 0 4px; }
.tachos .uhr { align-self: center; }
.widget .tachos svg { max-width: 220px; margin: 0 auto; }
@media (max-width: 520px) { .tachos { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); } .tachos .uhr { grid-column: 1 / -1; order: -1; } }
.widget .ks .btn { font-size: .85rem; padding: 3px 10px; }
.widget .zweispaltig { gap: 10px; }
.dia-pfeile { display: flex; justify-content: center; gap: 10px 28px; flex-wrap: wrap; margin: 2px 0; font-size: .88rem; font-weight: 700; }
.dia-pfeile .ab { color: var(--ok); }
.dia-pfeile .auf { color: var(--mb); }
.formel-tabelle { border-collapse: collapse; margin: 10px 0; font-size: .98rem; display: block; overflow-x: auto; }
.formel-tabelle th, .formel-tabelle td { border: 1px solid var(--line); padding: 6px 12px; text-align: left; vertical-align: middle; }
.formel-tabelle th { background: var(--surface-2); }
.widget .zweispaltig { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
@media (max-width: 700px) { .widget .zweispaltig { grid-template-columns: 1fr; } }
@media (max-width: 700px) { .widget .regler { grid-auto-flow: row dense; } }
.le-karte-kopf h2 { flex: 1 1 14em; overflow-wrap: break-word; hyphens: auto; -webkit-hyphens: auto; }