/* site.css — Design-System der Mehrseiten-Website "Operations Research mit
   Python". Struktur (CSS-Variablen, .dark-Umschaltung, kuehle Graustufen)
   nach dem Vorbild https://jamulix.de/sorting/, Farben aus der bestehenden
   Buchpalette (Titelseite/PDF: Indigo/Cyan/Violett/Gruen/Amber). */

:root {
  --bg: #f5f6fa;
  --surface: #ffffff;
  --surface2: #eef0f5;
  --border: #d9dce6;
  --text: #1a1a2e;
  --muted: #5c6380;
  --accent: #4338ca;
  --accent-text: #ffffff;
  --cyan: #0891b2;
  --violett: #7c3aed;
  --emerald: #059669;
  --amber: #b45309;
  --rose: #e11d48;
  --tint-indigo: #eef2ff;
  --tint-violett: #f5f3ff;
  --tint-cyan: #ecfeff;
  --tint-emerald: #ecfdf5;
  --tint-amber: #fffbeb;
  --code-bg: #1e293b;
  --code-text: #e6edf3;
  --shadow: 0 2px 10px rgba(26, 26, 46, .07);
  --shadow-lg: 0 8px 30px rgba(26, 26, 46, .12);
  --radius: 12px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0e0f1a;
    --surface: #161826;
    --surface2: #1e2133;
    --border: #2b2f45;
    --text: #e7e9f5;
    --muted: #9aa1c4;
    --accent: #818cf8;
    --accent-text: #0e0f1a;
    --cyan: #22d3ee;
    --violett: #c4b5fd;
    --emerald: #34d399;
    --amber: #fbbf24;
    --rose: #fb7185;
    --tint-indigo: #1b1f3a;
    --tint-violett: #241f3d;
    --tint-cyan: #132833;
    --tint-emerald: #10291f;
    --tint-amber: #2c2410;
    --code-bg: #0b0d14;
    --code-text: #dbe4f0;
    --shadow: 0 2px 10px rgba(0, 0, 0, .35);
    --shadow-lg: 0 8px 30px rgba(0, 0, 0, .5);
  }
}

:root[data-theme="dark"] {
  --bg: #0e0f1a;
  --surface: #161826;
  --surface2: #1e2133;
  --border: #2b2f45;
  --text: #e7e9f5;
  --muted: #9aa1c4;
  --accent: #818cf8;
  --accent-text: #0e0f1a;
  --cyan: #22d3ee;
  --violett: #c4b5fd;
  --emerald: #34d399;
  --amber: #fbbf24;
  --rose: #fb7185;
  --tint-indigo: #1b1f3a;
  --tint-violett: #241f3d;
  --tint-cyan: #132833;
  --tint-emerald: #10291f;
  --tint-amber: #2c2410;
  --code-bg: #0b0d14;
  --code-text: #dbe4f0;
  --shadow: 0 2px 10px rgba(0, 0, 0, .35);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, .5);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, "DejaVu Sans", Arial, sans-serif;
  line-height: 1.7; font-size: 16px; -webkit-text-size-adjust: 100%;
}
.icon { width: 1.15em; height: 1.15em; flex: none; vertical-align: -.2em; }

/* --- Kopfzeile --- */
.site-header {
  position: sticky; top: 0; z-index: 30; display: flex; align-items: center;
  gap: .75rem; padding: .6rem 1rem; background: var(--surface);
  border-bottom: 1px solid var(--border); box-shadow: var(--shadow);
}
.icon-btn {
  display: flex; align-items: center; justify-content: center;
  width: 2.2rem; height: 2.2rem; border-radius: 8px; border: 1px solid transparent;
  background: transparent; color: var(--text); cursor: pointer;
}
.icon-btn:hover { background: var(--surface2); border-color: var(--border); }
.brand {
  display: flex; align-items: center; gap: .5rem; color: var(--accent);
  font-weight: 700; text-decoration: none; white-space: nowrap;
}
.brand span { display: none; }
@media (min-width: 900px) { .brand span { display: inline; } }
.site-search { position: relative; flex: 1; max-width: 420px; margin: 0 auto; }
.site-search input {
  width: 100%; padding: .5rem .8rem .5rem 2.2rem; border-radius: 20px;
  border: 1px solid var(--border); background: var(--surface2); color: var(--text);
  font-size: .92rem;
}
.site-search input:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.such-icon { position: absolute; left: .7rem; top: 50%; transform: translateY(-50%); color: var(--muted); }
.suche-ergebnisse {
  position: absolute; top: calc(100% + .4rem); left: 0; right: 0; max-height: 60vh;
  overflow-y: auto; background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow-lg); z-index: 40;
}
.suche-ergebnisse a {
  display: block; padding: .55rem .9rem; color: var(--text); text-decoration: none;
  border-bottom: 1px solid var(--border);
}
.suche-ergebnisse a:last-child { border-bottom: none; }
.suche-ergebnisse a:hover, .suche-ergebnisse a.aktiv { background: var(--tint-indigo); }
.suche-ergebnisse small { display: block; color: var(--muted); font-weight: 400; }
.suche-leer { padding: .8rem .9rem; color: var(--muted); }
#theme-toggle .icon-moon { display: none; }
:root[data-theme="dark"] #theme-toggle .icon-sun { display: none; }
:root[data-theme="dark"] #theme-toggle .icon-moon { display: inline; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) #theme-toggle .icon-sun { display: none; }
  :root:not([data-theme="light"]) #theme-toggle .icon-moon { display: inline; }
}

/* --- Layout: Sidebar + Inhalt --- */
.site-body { display: flex; align-items: flex-start; max-width: 1400px; margin: 0 auto; }
.sidebar {
  position: sticky; top: 3.6rem; width: 290px; flex: none;
  height: calc(100vh - 3.6rem); overflow-y: auto; border-right: 1px solid var(--border);
  background: var(--surface); padding: 1rem 0;
}
.sidebar-gruppe { border-bottom: 1px solid var(--border); }
.sidebar-gruppe summary {
  cursor: pointer; padding: .6rem 1rem; font-weight: 700; color: var(--accent);
  list-style: none; display: flex; align-items: center; justify-content: space-between;
}
.sidebar-gruppe summary::-webkit-details-marker { display: none; }
.sidebar-gruppe summary::after { content: "▾"; color: var(--muted); font-size: .8em; }
.sidebar-gruppe[open] summary::after { content: "▴"; }
.sidebar ul { list-style: none; margin: 0; padding: 0 .5rem .5rem; }
.sidebar li a {
  display: flex; align-items: center; gap: .5rem; padding: .4rem .6rem;
  border-radius: 8px; color: var(--text); text-decoration: none; font-size: .92rem;
}
.sidebar li a:hover { background: var(--tint-indigo); }
.sidebar li.aktiv a { background: var(--accent); color: var(--accent-text); font-weight: 600; }
.fortschritt-haken { width: 1em; height: 1em; color: var(--emerald); visibility: hidden; }
.fortschritt-haken .icon { width: 100%; height: 100%; }
li[data-erledigt="1"] .fortschritt-haken { visibility: visible; }
.sidebar-extra { border-top: 2px solid var(--border); margin-top: .5rem; padding-top: .8rem !important; }
.sidebar-overlay { display: none; }

.content { flex: 1; min-width: 0; padding: 1.5rem 2rem 5rem; max-width: 900px; margin: 0 auto; }

/* --- Breadcrumb, Prev/Next --- */
.breadcrumb { font-size: .85rem; color: var(--muted); margin-bottom: .8rem; }
.breadcrumb a { color: var(--muted); }
.prev-next { display: flex; justify-content: space-between; gap: 1rem; margin: 1.2rem 0; }
.prev-next-knopf {
  display: flex; align-items: center; gap: .6rem; flex: 1; max-width: 48%;
  padding: .7rem 1rem; border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--surface); color: var(--text); text-decoration: none; font-size: .9rem;
  box-shadow: var(--shadow); transition: border-color .15s, transform .15s;
}
.prev-next-knopf:hover { border-color: var(--accent); transform: translateY(-1px); }
.prev-next-next { margin-left: auto; text-align: right; flex-direction: row-reverse; }
.prev-next-knopf small { display: block; color: var(--muted); font-weight: 400; }
.prev-next-leer { flex: 1; max-width: 48%; }

.fortschritt-knopf {
  display: inline-flex; align-items: center; gap: .5rem; margin: 1rem 0;
  padding: .55rem 1rem; border-radius: 20px; border: 1px solid var(--border);
  background: var(--surface2); color: var(--text); cursor: pointer; font: inherit; font-size: .88rem;
}
.fortschritt-knopf .icon { color: var(--muted); }
.fortschritt-knopf.erledigt { background: var(--tint-emerald); border-color: var(--emerald); color: var(--emerald); }
.fortschritt-knopf.erledigt .icon { color: var(--emerald); }

.site-footer { text-align: center; padding: 1.5rem; color: var(--muted); font-size: .85rem; border-top: 1px solid var(--border); }
.site-footer a { color: var(--muted); }

/* --- Typografie im Artikel (angelehnt an bilder/or_html_style.html) --- */
article h1, article h2, article h3, article h4, article h5 {
  line-height: 1.25; font-weight: 700; margin-top: 2.1em; margin-bottom: .6em; scroll-margin-top: 4.5rem;
}
article h1 { color: var(--accent); font-size: 1.9rem; border-bottom: 3px solid var(--accent); padding-bottom: .25em; }
article h2 { color: var(--accent); font-size: 1.45rem; border-bottom: 2px solid var(--border); padding-bottom: .2em; }
article h3 { color: var(--cyan); font-size: 1.18rem; }
article h4 { color: var(--violett); font-size: 1.05rem; }
article h2[id$="-lernziele"]::before { content: "🎯 "; }
article h2[id$="-uebungsaufgaben"]::before { content: "📝 "; }
article h2[id$="-selbsttest"]::before { content: "✅ "; }
article h2[id$="-zusammenfassung"]::before { content: "📌 "; }
article a { color: var(--accent); text-decoration: none; }
article a:hover { text-decoration: underline; }
article a[target="_blank"]::after { content: " \2197"; font-size: .82em; color: var(--cyan); text-decoration: none; }
article p { margin: .75em 0; }
article hr { border: 0; border-top: 1px solid var(--border); margin: 2.2em 0; }
article figure { margin: 2em 0; text-align: center; }
article img { max-width: 100%; height: auto; display: block; margin: 0 auto; border-radius: 10px; }
article figure img { box-shadow: var(--shadow-lg); }
article figcaption { color: var(--muted); font-size: .9rem; font-style: italic; margin-top: .6em; }
article table { border-collapse: collapse; width: 100%; margin: 1.4em 0; font-size: .94rem; box-shadow: var(--shadow); border-radius: 8px; overflow: hidden; }
article th { background: var(--accent); color: var(--accent-text); font-weight: 700; text-align: left; }
article th, article td { padding: .55em .75em; border: 1px solid var(--border); vertical-align: top; }
article tbody tr:nth-child(even) { background: var(--tint-indigo); }
article code { font-family: "DejaVu Sans Mono", Consolas, Menlo, monospace; font-size: .9em; background: var(--tint-violett); color: var(--violett); padding: .12em .4em; border-radius: 5px; }
article pre { background: var(--code-bg); color: var(--code-text); padding: 1.1em 1.2em; border-radius: 10px; overflow-x: auto; line-height: 1.5; font-size: .85rem; box-shadow: var(--shadow-lg); }
article pre code { background: none; color: inherit; padding: 0; font-size: inherit; }
article div.sourceCode { position: relative; }
article div.sourceCode pre.sourceCode { padding-top: 2.6em; }
article blockquote { border-left: 4px solid var(--violett); background: var(--tint-violett); margin: 1.4em 0; padding: .6em 1.2em; border-radius: 0 8px 8px 0; }
article ul, article ol { padding-left: 1.4em; }
article li { margin: .3em 0; }
.katex-display { overflow-x: auto; overflow-y: hidden; padding: .4em 0; }

/* --- Code-Buttons (Kopieren / Herunterladen) --- */
.code-btn-leiste { position: absolute; top: .55em; right: .55em; z-index: 2; display: flex; gap: .4em; }
.code-btn, .download-link {
  display: inline-flex; align-items: center; gap: .35em; background: rgba(255,255,255,.08);
  color: #cbd5e1; border: 1px solid rgba(255,255,255,.18); border-radius: 6px;
  padding: .3em .65em; font: inherit; font-size: .78rem; cursor: pointer;
  text-decoration: none !important; transition: background .15s, color .15s;
}
.code-btn:hover, .download-link:hover { background: rgba(255,255,255,.18); color: #fff; }
.code-btn.copied { background: var(--emerald); color: #fff; border-color: var(--emerald); }
.download-link { position: static; margin-left: .6em; }

/* --- Karten (Kapitel auf einen Blick, Lernpfade, Kapitelraster) --- */
.card { border-radius: var(--radius); padding: 1.1em 1.4em; margin: 1.6em 0; box-shadow: var(--shadow); }
.card p, .card blockquote { margin: .5em 0 !important; border: none !important; background: none !important; padding: 0 !important; }
.card-blick { background: var(--tint-indigo); border: 1px solid var(--accent); }
.card-blick blockquote { border-left: 3px solid var(--accent); padding-left: .8em !important; }

/* --- Didaktische Karten der Version 04 ---------------------------------
   Jede Kartenart traegt eine eigene Leitfarbe aus der Buchpalette, damit
   Kursteilnehmer beim Blaettern sofort erkennen, was sie vor sich haben:
   gruen = sofort ausprobieren, cyan = Formel im Klartext, violett = Excel,
   amber = Selbstkontrolle, rose = hier steckt ein Fehler drin. Die
   Leitfarbe liegt links als 5px-Balken, damit sie auch im Ausdruck und in
   der Druckvorschau erkennbar bleibt. */
.card-schnellstart,
.card-formel,
.card-excel,
.card-quiz,
.card-denkfehler { border: 1px solid var(--border); border-left-width: 5px; }

.card-schnellstart { background: var(--tint-emerald); border-left-color: var(--emerald); }
.card-formel       { background: var(--tint-cyan);    border-left-color: var(--cyan); }
.card-excel        { background: var(--tint-violett); border-left-color: var(--violett); }
.card-quiz         { background: var(--tint-amber);   border-left-color: var(--amber); }
.card-denkfehler   { background: var(--tint-amber);   border-left-color: var(--rose); }

/* Die Karten enthalten haeufig Tabellen (Formel-Uebersetzer) und
   Codebloecke (Schnellstart, Denkfehler). Beide sollen sich klar vom
   getoenten Kartengrund abheben statt darin zu verschwimmen. */
.card-schnellstart pre,
.card-denkfehler pre { margin: .8em 0 !important; }
.card-formel table { margin: .6em 0; background: var(--surface); }
.card-formel td:first-child { white-space: nowrap; }

/* --- Interaktive Plotly-Figuren ---------------------------------------
   Stehen im Text unmittelbar hinter der statischen Fassung (die im PDF
   gedruckt wird). Auf schmalen Displays darf die Figur horizontal
   scrollen, statt die Seite selbst breit zu machen. */
.plotly-figur { margin: 1.4em 0; background: var(--surface); border: 1px solid var(--border);
                border-radius: var(--radius); padding: .6em; overflow-x: auto; }
.plotly-figur .plotly-graph-div { min-width: 320px; }

/* Leaflet-Karte im iframe ({karte:...}). Der Rahmen kommt von hier, nicht vom
   iframe selbst - dessen Standardrahmen passt zu keinem der beiden Themen. */
.karte-figur { display: block; width: 100%; height: 30rem; margin: 1.4em 0;
               border: 1px solid var(--border); border-radius: var(--radius);
               background: var(--surface); }
@media (max-width: 640px) { .karte-figur { height: 22rem; } }

/* Der Formel-Uebersetzer ist zweispaltig gedacht: links die Mathematik,
   rechts der Klartext. Auf schmalen Displays wuerde die Formelspalte die
   Tabelle sonst aus dem Viewport druecken. */
@media (max-width: 640px) {
  .card-formel td:first-child { white-space: normal; }
}

.kartenraster { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 1rem; margin: 1rem 0 2rem; }
.karte { display: block; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.1rem; box-shadow: var(--shadow); text-decoration: none; color: var(--text); }
.karte:hover { border-color: var(--accent); transform: translateY(-2px); transition: transform .15s, border-color .15s; }
.karte h3 { margin: .3em 0; color: var(--text); font-size: 1.05rem; }
.karte p { color: var(--muted); font-size: .88rem; margin: .4em 0; }
.karte-nummer { font-size: .78rem; font-weight: 700; color: var(--accent); text-transform: uppercase; letter-spacing: .03em; }
.karte-zeit { font-size: .8rem; color: var(--muted); }
.karte-pfad { background: var(--tint-violett); border-color: var(--violett); }
.karte-einstieg { background: var(--tint-cyan); border-color: var(--cyan); }
.kapitelgruppe { margin: 2.5rem 0; }
.kapitelgruppe h2 { color: var(--accent); border-bottom: 2px solid var(--border); padding-bottom: .3em; }
.lernpfade h2 { color: var(--violett); }

/* --- Landing-Page Hero --- */
.hero { margin: 1rem 0 2.5rem; }
.hero-kicker { color: var(--cyan); letter-spacing: .12em; font-weight: 700; font-size: .85rem; }
.hero-text h1 { font-size: 2.1rem; color: var(--accent); margin: .2em 0; }
.hero-untertitel { color: var(--muted); font-size: 1.05rem; }
.hero-badges { display: flex; gap: .6rem; margin-top: 1rem; flex-wrap: wrap; }
.hero-kompendium { color: var(--muted); margin-top: 1.4rem; max-width: 640px; }
.hero-anwendungen { color: var(--muted); margin-top: .8rem; max-width: 640px; }
.hero-autor { color: var(--muted); font-size: .92rem; line-height: 1.5; }
.badge { padding: .35em .9em; border-radius: 20px; color: #fff; font-weight: 600; font-size: .85rem; }
.badge-indigo { background: var(--accent); }
.badge-cyan { background: var(--cyan); }
.badge-violett { background: var(--violett); }
.badge-emerald { background: var(--emerald); }

/* --- Programme-Seite --- */
.programmgruppe { margin: 2rem 0; }
.programmliste { list-style: none; padding: 0; }
.programmliste li { display: flex; align-items: center; justify-content: space-between; padding: .5em .8em; border: 1px solid var(--border); border-radius: 8px; margin: .4em 0; background: var(--surface); }

/* --- Stichwortverzeichnis --- */
.register-sprungleiste { display: flex; flex-wrap: wrap; gap: .3rem; margin: 1.2rem 0 1.8rem; position: sticky; top: 3.6rem; background: var(--bg); padding: .5rem 0; z-index: 5; }
.register-sprungleiste a { display: inline-flex; align-items: center; justify-content: center; width: 1.8rem; height: 1.8rem; border-radius: 6px; background: var(--surface2); color: var(--accent); text-decoration: none; font-weight: 700; font-size: .85rem; }
.register-sprungleiste a:hover { background: var(--tint-indigo); }
.register-buchstabe { color: var(--accent); border-bottom: 2px solid var(--border); padding-bottom: .15em; margin-top: 2em; font-size: 1.3rem; }
.register-eintrag { padding: .55em 0; border-bottom: 1px solid var(--border); }
.register-begriff { font-weight: 700; }
.register-eintrag a { font-size: .92rem; }
.register-unter { list-style: none; margin: .4em 0 0; padding-left: 1.4em; }
.register-unter li { margin: .3em 0; color: var(--muted); font-size: .92rem; }
.register-unter a { font-size: inherit; }

/* --- Mobile --- */
@media (max-width: 899px) {
  .sidebar {
    position: fixed; top: 0; left: 0; height: 100vh; z-index: 50; transform: translateX(-105%);
    transition: transform .2s ease; box-shadow: var(--shadow-lg); padding-top: 3.6rem;
  }
  .sidebar.offen { transform: translateX(0); }
  .sidebar-overlay.offen { display: block; position: fixed; inset: 0; background: rgba(0,0,0,.4); z-index: 40; }
  .content { padding: 1.2rem 1rem 4rem; }
  .site-search { max-width: none; }
}