:root {
  --bg: #fff;
  --terracotta: #c0562e;
  --warn-bg: #fff3ea;
  --card-bg: #faf8f5;
  --card-neutral: #fff;
  --card-border: #eee;
  --good: #4a7c59;
  --good-bg: #f0f7f0;
  --correction: #c1272d;
  --text: #2b2b2b;
}

:root[data-theme="dark"] {
  --bg: #171513;
  --terracotta: #e08a5b;
  --warn-bg: #3a2a1f;
  --card-bg: #26221f;
  --card-neutral: #1e1c1a;
  --card-border: #423c37;
  --good: #7ab88a;
  --good-bg: #1f2e22;
  --correction: #e5726b;
  --text: #ece6e0;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  transition: background-color 0.15s ease, color 0.15s ease;
}

a { color: var(--terracotta); }

header.site-header {
  background: var(--bg);
  border-bottom: 1px solid var(--card-border);
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.header-werkzeuge {
  display: flex;
  align-items: center;
  gap: 10px;
}

.header-werkzeuge button,
.header-werkzeuge select {
  font-family: inherit;
  font-size: 0.9em;
  background: var(--card-bg);
  color: var(--text);
  border: 1px solid var(--card-border);
  border-radius: 6px;
  padding: 4px 8px;
  cursor: pointer;
}

header.site-header .brand {
  font-weight: bold;
  font-size: 1.2em;
  color: var(--terracotta);
  text-decoration: none;
}

header.site-header nav a {
  margin-left: 16px;
  text-decoration: none;
  color: var(--text);
  font-size: 0.95em;
}

main {
  max-width: 900px;
  margin: 0 auto;
  padding: 24px 20px 60px;
}

footer.site-footer {
  background: var(--card-bg);
  border-top: 1px solid var(--card-border);
  padding: 20px;
  margin-top: 40px;
  font-size: 0.85em;
  color: var(--text);
  opacity: 0.7;
  text-align: center;
}

footer.site-footer a {
  color: inherit;
  margin: 0 8px;
}

/* Kachel-Grid (Startseite) */
.kachel-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 20px;
}

.kachel-card {
  position: relative;
  display: block;
  text-decoration: none;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 10px;
  padding: 20px;
  color: var(--text);
  transition: box-shadow 0.15s ease, transform 0.15s ease;
}

.zensur-punkt {
  position: absolute;
  top: 10px;
  right: 10px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #e5484d;
  box-shadow: 0 0 0 2px rgba(229, 72, 77, 0.25), 0 0 6px 1px rgba(229, 72, 77, 0.6);
}

.kachel-card:hover {
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.kachel-card .emoji { font-size: 2em; display: block; margin-bottom: 8px; }
.kachel-card .title { font-weight: bold; color: var(--terracotta); }

/* Seitenabschnitte */
section.block { margin: 32px 0; }
section.block h2 {
  color: var(--terracotta);
  font-size: 1.5em;
  border-bottom: 2px solid var(--card-border);
  padding-bottom: 8px;
}
section.block h3 {
  margin-top: 28px;
  font-size: 1.05em;
  letter-spacing: 0.02em;
}

/* Sprungmarken-Leiste oben auf der Seite */
.abschnitt-nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin: 4px 0 24px;
}

.abschnitt-nav a {
  text-decoration: none;
  font-size: 0.85em;
  font-weight: bold;
  color: var(--terracotta);
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  padding: 6px 14px;
  border-radius: 20px;
}

.abschnitt-nav a:hover { background: var(--warn-bg); }

/* Dezenterer Rahmen für Abschnitte, die auffallen aber nicht mit .hervorgehoben konkurrieren sollen */
section.eingerahmt {
  border: 2px solid var(--terracotta);
  border-radius: 10px;
  padding: 20px;
}

/* Hervorgehobener Abschnitt — für "Üben" auf jeder Wissenskachel, muss sofort auffallen */
section.hervorgehoben {
  background: var(--warn-bg);
  border-top: 4px solid var(--terracotta);
  border-bottom: 4px solid var(--terracotta);
  border-radius: 10px;
  padding: 20px 20px 24px;
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.15);
}

/* Innerhalb des hervorgehobenen Abschnitts braucht die Hinweis-Box eigenen Kontrast */
section.hervorgehoben .hint-box { background: var(--card-neutral); }

/* Bonus-Box: Zusatzaufgabe für die Schnellen, dritte optische Ebene neben Pflicht-Inhalt und details-Vertiefung */
.bonus-box {
  background: var(--good-bg);
  border: 1px dashed var(--good);
  border-radius: 8px;
  padding: 12px 16px;
  margin: 16px 0;
}

.bonus-box .bonus-label {
  display: inline-block;
  font-weight: bold;
  color: var(--good);
  margin-bottom: 4px;
}

/* Mini-Kanban-Demo: live ausprobierbar, nicht nur ein Link */
.kanban-demo {
  display: flex;
  gap: 10px;
  margin: 16px 0;
  flex-wrap: wrap;
}

.kanban-spalte {
  flex: 1;
  min-width: 160px;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 8px;
  padding: 10px;
  min-height: 180px;
}

.kanban-spalte h4 {
  margin: 0 0 8px;
  font-size: 0.9em;
  color: var(--terracotta);
  text-align: center;
}

.kanban-spalte.drag-ueber { background: var(--warn-bg); }

.kanban-karte {
  background: var(--card-neutral);
  border: 1px solid var(--card-border);
  border-radius: 6px;
  padding: 8px 10px;
  margin-bottom: 8px;
  font-size: 0.9em;
  cursor: grab;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.kanban-karte:active { cursor: grabbing; }

/* Feynman-Selbsttest */
.feynman-box {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 8px;
  padding: 16px;
  margin: 16px 0;
}

.feynman-schluesselwort {
  display: inline-block;
  border-radius: 12px;
  padding: 3px 10px;
  margin: 3px 4px 3px 0;
  font-size: 0.85em;
  font-weight: bold;
}

.feynman-schluesselwort.gefunden { background: var(--good-bg); color: var(--good); }
.feynman-schluesselwort.fehlt { background: var(--warn-bg); color: var(--terracotta); }

/* Fixierte Zurück/Weiter-Leiste zwischen Kacheln */
body.hat-kachel-nav { padding-bottom: 68px; }

.kachel-nav-fix {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--card-neutral);
  border-top: 1px solid var(--card-border);
  box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.08);
  display: flex;
  justify-content: space-between;
  align-items: stretch;
  z-index: 20;
}

.kachel-nav-fix a, .kachel-nav-fix span.leer {
  flex: 1;
  padding: 10px 14px;
  text-decoration: none;
  color: var(--text);
  font-size: 0.85em;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.kachel-nav-fix a.weiter { text-align: right; }

.kachel-nav-fix a.home {
  flex: 0 0 auto;
  align-items: center;
  justify-content: center;
  font-size: 1.3em;
  padding: 10px 18px;
  border-left: 1px solid var(--card-border);
  border-right: 1px solid var(--card-border);
}

.kachel-nav-fix a:hover { background: var(--card-bg); }

.kachel-nav-fix .label { opacity: 0.6; font-size: 0.85em; }
.kachel-nav-fix .titel { font-weight: bold; color: var(--terracotta); }

.hint-box {
  background: var(--warn-bg);
  border-left: 4px solid var(--terracotta);
  padding: 10px 14px;
  border-radius: 4px;
  margin: 16px 0;
}

video { max-width: 100%; border-radius: 8px; }

details summary {
  color: var(--terracotta);
  font-weight: bold;
  cursor: pointer;
}

table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 6px 8px; border: 1px solid var(--card-border); }

.eingabe-tabelle td[contenteditable="true"] {
  background: var(--card-neutral);
  cursor: text;
  min-width: 90px;
}
.eingabe-tabelle td[contenteditable="true"]:empty::before {
  content: attr(data-platzhalter);
  opacity: 0.4;
}
.eingabe-tabelle td[contenteditable="true"]:focus {
  outline: 2px solid var(--terracotta);
  outline-offset: -2px;
}

select, input {
  font-family: inherit;
  background: var(--card-neutral);
  color: var(--text);
  border: 1px solid var(--card-border);
  border-radius: 4px;
  padding: 4px 6px;
}

/* Stundenaufgabe: Vertiefungs-Auswahl */
.vertiefung-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin: 16px 0;
}

.vertiefung-card {
  display: block;
  background: var(--card-neutral);
  border: 1px solid var(--card-border);
  border-radius: 8px;
  padding: 16px;
  text-align: center;
  color: var(--text);
  text-decoration: none;
  transition: box-shadow 0.15s ease, transform 0.15s ease;
}

a.vertiefung-card:hover {
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.vertiefung-card .emoji { font-size: 1.8em; display: block; margin-bottom: 6px; }

/* Dateiformate: Kategorie-Raster */
.formate-kategorie {
  margin: 22px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--card-border);
}

.formate-kategorie:first-child {
  margin-top: 10px;
  padding-top: 0;
  border-top: none;
}

.formate-kategorie-titel {
  font-weight: bold;
  color: var(--terracotta);
  font-size: 1.05em;
  margin: 0 0 10px;
}

.formate-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
}

.format-karte {
  background: var(--card-neutral);
  border: 1px solid var(--card-border);
  border-radius: 8px;
  padding: 14px 10px;
  text-align: center;
}

.format-karte .emoji { font-size: 1.7em; display: block; margin-bottom: 4px; }

.format-karte .endung {
  display: block;
  font-weight: bold;
  color: var(--terracotta);
  margin-bottom: 4px;
}

.format-karte .zweck {
  font-size: 0.8em;
  opacity: 0.75;
  margin: 0;
  min-height: 2.4em;
}

.format-groesse {
  display: flex;
  justify-content: center;
  gap: 3px;
  margin-top: 8px;
}

.format-groesse span {
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--card-border);
}

.format-groesse span.aktiv { background: var(--terracotta); }

.format-groesse-label {
  font-size: 0.72em;
  opacity: 0.6;
  margin: 3px 0 0;
}

/* Uebung */
.frage {
  background: var(--card-neutral);
  border: 1px solid var(--card-border);
  border-radius: 8px;
  padding: 16px;
  margin: 12px 0;
}

.frage button.antwort {
  display: block;
  width: 100%;
  text-align: left;
  padding: 10px 12px;
  margin: 6px 0;
  border: 1px solid var(--card-border);
  border-radius: 6px;
  background: var(--card-neutral);
  color: var(--text);
  cursor: pointer;
  font-size: 1em;
}

.frage button.antwort:hover { background: var(--card-bg); }

.feedback {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 6px;
  font-size: 0.95em;
  display: none;
}

.feedback.richtig { background: var(--good-bg); border-left: 4px solid var(--good); display: block; }
.feedback.falsch { background: var(--warn-bg); border-left: 4px solid var(--terracotta); display: block; }

.loesungs-hinweis {
  display: inline-block;
  margin-top: 8px;
  font-size: 0.85em;
  color: var(--terracotta);
  text-decoration: underline;
  cursor: pointer;
}

.loesungs-hinweis:hover { opacity: 0.8; }

/* Keycap: Tasten als kleine physische Taste darstellen */
kbd.taste {
  display: inline-block;
  background: var(--card-neutral);
  border: 1px solid var(--card-border);
  border-bottom-width: 3px;
  border-radius: 6px;
  padding: 2px 8px;
  margin: 0 1px;
  font-family: inherit;
  font-weight: bold;
  font-size: 0.9em;
  color: var(--text);
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.05);
}

code, pre {
  background: var(--card-bg);
  color: var(--text);
  border: 1px solid var(--card-border);
  border-radius: 4px;
}
pre { padding: 10px; overflow-x: auto; }
code { padding: 1px 5px; }

/* Lernkarten */
.lernkarte-wurzel {
  max-width: 420px;
  margin: 16px auto;
}

.lernkarte {
  perspective: 1000px;
  height: 180px;
  cursor: pointer;
}

.lernkarte-innen {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.5s;
  transform-style: preserve-3d;
}

.lernkarte.umgedreht .lernkarte-innen { transform: rotateY(180deg); }

.lernkarte-seite {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  border-radius: 10px;
  border: 1px solid var(--card-border);
  background: var(--card-bg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 16px;
  font-size: 1.1em;
}

.lernkarte-seite.vorn { font-weight: bold; color: var(--terracotta); }

.lernkarte-seite.hinten {
  background: var(--good-bg);
  transform: rotateY(180deg);
}

.lernkarte-steuerung {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 10px;
  font-size: 0.9em;
  color: #777;
}