/* Lehrveranstaltungsübersicht – barrierearmes Stylesheet
   Systemschriften (keine externen Schriftdienste, datenschutzfreundlich) */

:root {
  --bg: #ffffff;
  --surface: #eef3f8;
  --ink: #16202b;
  --muted: #465364;
  --primary: #0b4a84;
  --primary-ink: #ffffff;
  --line: #b9c6d3;
  --row-alt: #f6f8fb;
  --focus: #b54708;
  --error: #a4161a;
  --error-bg: #fdecec;
  --band: #0b4a84;
  --band-ink: #ffffff;
  --band-link: #ffffff;

  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --radius: 6px;
  color-scheme: light;
}

:root[data-theme="dark"] {
  --bg: #0f151c;
  --surface: #17212c;
  --ink: #e6ecf2;
  --muted: #aebbc9;
  --primary: #8fc3ff;
  --primary-ink: #0f151c;
  --line: #3a4a5a;
  --row-alt: #131b24;
  --focus: #ffb35c;
  --error: #ffb4b4;
  --error-bg: #3a1618;
  --band: #0a2744;
  --band-ink: #e6ecf2;
  --band-link: #ffffff;
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.5;
}

.wrap { max-width: 90rem; margin: 0 auto; padding: 0 1.25rem; }

a { color: var(--primary); text-underline-offset: 0.15em; }

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.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;
}

.skip-link {
  position: absolute;
  left: 1rem; top: -4rem;
  z-index: 10;
  padding: 0.6rem 1rem;
  background: var(--bg);
  color: var(--primary);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  font-weight: 600;
}
.skip-link:focus { top: 1rem; }

/* ---------- Kopfbereich ---------- */

.site-header { background: var(--band); color: var(--band-ink); }

.header-inner {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between;
  gap: 0.75rem 1.5rem;
  padding-top: 0.75rem; padding-bottom: 0.75rem;
}

.site-name { margin: 0; font-weight: 700; font-size: 1.05rem; }
.site-name a { color: var(--band-link); text-decoration: none; }
.site-name a:hover { text-decoration: underline; }
.site-name span { font-weight: 400; opacity: 0.92; }

.header-tools { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; }

.lang-switch { display: flex; gap: 0.25rem; margin: 0; padding: 0; list-style: none; }
.lang-switch a {
  display: inline-block;
  min-height: 44px; min-width: 44px;
  padding: 0.55rem 0.8rem;
  color: var(--band-link);
  border-radius: var(--radius);
  text-decoration: underline;
}
.lang-switch a[aria-current="page"] {
  background: var(--band-link);
  color: var(--band);
  text-decoration: none;
  font-weight: 700;
}

.site-header :focus-visible { outline-color: #ffd28a; }

.theme-toggle {
  min-height: 44px;
  padding: 0.5rem 0.9rem;
  font: inherit;
  color: var(--band-link);
  background: transparent;
  border: 2px solid var(--band-link);
  border-radius: var(--radius);
  cursor: pointer;
}
.theme-toggle[aria-pressed="true"] { background: var(--band-link); color: var(--band); }

/* ---------- Hauptbereich ---------- */

main { padding: 2rem 0 3rem; }
main:focus { outline: none; }

h1 {
  margin: 0 0 0.35rem;
  font-size: clamp(1.75rem, 1.2rem + 2.6vw, 3rem);
  overflow-wrap: break-word;
  hyphens: auto;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

h2 { font-size: 1.2rem; margin: 0 0 0.75rem; }

.meta { margin: 0 0 1.75rem; color: var(--muted); }
.meta strong { color: var(--ink); }
#data-source:not(:empty)::before { content: " | "; }

.panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1rem 1.25rem 1.25rem;
  margin-bottom: 1.25rem;
}

.hint { margin: 0.4rem 0 0; font-size: 0.9rem; color: var(--muted); max-width: 70ch; }

.status:empty { display: none; }
.status { margin: 0 0 1.25rem; font-weight: 600; }
.status.error {
  color: var(--error);
  background: var(--error-bg);
  border-left: 4px solid var(--error);
  padding: 0.5rem 0.75rem;
}

/* Filter */
.filter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  gap: 1rem;
  align-items: end;
}
.field { display: flex; flex-direction: column; gap: 0.3rem; min-width: 0; }
.field label { font-weight: 600; }
.field-search { grid-column: span 2; }
@media (max-width: 34rem) { .field-search { grid-column: auto; } }

.filter-grid .field-reset { align-self: end; }

input[type="search"], select {
  width: 100%;
  min-height: 44px;
  padding: 0.5rem 0.65rem;
  font: inherit;
  color: var(--ink);
  background: var(--bg);
  border: 1px solid var(--muted);
  border-radius: var(--radius);
}

.btn-secondary {
  min-height: 44px;
  padding: 0.5rem 1rem;
  font: inherit; font-weight: 600;
  color: var(--primary);
  background: var(--bg);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  cursor: pointer;
}
.btn-secondary:hover { background: var(--surface); }

.field-search .hint { margin-top: 0; }
.filter-grid { align-items: start; }

/* Ergebnisse */
.count {
  font-size: 1.1rem; font-weight: 700;
  margin: 1.5rem 0 0;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--line);
}

/* ---------- Lehrveranstaltung (Vorlesung, Übung usw. gebündelt) ---------- */

.course {
  padding: 1.25rem 0 1.4rem;
  border-bottom: 1px solid var(--line);
}

.course-title {
  margin: 0;
  font-size: 1.25rem;
  line-height: 1.3;
  color: var(--primary);
  overflow-wrap: break-word;
}

.course-alt {
  margin: 0.15rem 0 0;
  color: var(--muted);
  font-style: italic;
}

.course-meta {
  display: grid;
  gap: 0.2rem;
  margin: 0.75rem 0 0;
}
.course-meta div {
  display: grid;
  grid-template-columns: 8rem minmax(0, 1fr);
  gap: 1rem;
}
.course-meta dt { font-weight: 700; color: var(--muted); }
.course-meta dd { margin: 0; overflow-wrap: break-word; }

.sessions {
  list-style: none;
  margin: 0.9rem 0 0;
  padding: 0.15rem 0 0.15rem 1rem;
  border-left: 3px solid var(--line);
}

.session {
  display: grid;
  grid-template-columns: 9.5rem 10rem 8rem 5.5rem 7.5rem minmax(0, 1fr);
  gap: 0.2rem 1rem;
  padding: 0.3rem 0.5rem;
  border-radius: 4px;
  font-size: 0.95rem;
}
.session:nth-child(even) { background: var(--row-alt); }

.s-type { font-weight: 600; }
.s-time, .s-dur { font-variant-numeric: tabular-nums; white-space: nowrap; }
.s-room { overflow-wrap: break-word; }

.empty {
  margin-top: 1rem;
  padding: 1rem 1.25rem;
  border: 1px dashed var(--line);
  border-radius: var(--radius);
}

/* Mittlere Breite: engere Spalten */
@media (max-width: 68rem) {
  .session { grid-template-columns: 8.5rem 8.5rem 7rem 4.75rem 6.5rem minmax(0, 1fr); gap: 0.2rem 0.75rem; }
}

/* Schmal: Angaben der Beschreibungsliste untereinander */
@media (max-width: 38rem) {
  .course-meta div { grid-template-columns: minmax(0, 1fr); gap: 0; }
  .course-meta div + div { margin-top: 0.35rem; }
}

/* Schmal: Termine als fließender Text, Art als Überschrift der Zeile */
@media (max-width: 52rem) {
  .sessions { padding-left: 0.75rem; }
  .session {
    display: flex;
    flex-wrap: wrap;
    gap: 0.1rem 0.9rem;
    padding: 0.5rem;
  }
  .s-type { flex-basis: 100%; }
}

/* ---------- Fuß ---------- */

.site-footer {
  border-top: 1px solid var(--line);
  padding: 1.25rem 0 2rem;
  color: var(--muted);
  font-size: 0.9rem;
}
.site-footer p { margin: 0; max-width: 80ch; }

/* ---------- Bewegung, Kontrastmodus, Druck ---------- */

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}

@media (forced-colors: active) {
  .lang-switch a[aria-current="page"], .theme-toggle[aria-pressed="true"] { border: 2px solid CanvasText; }
  .sort-ind::before { forced-color-adjust: auto; }
}

@media print {
  .site-header, .filters, .skip-link { display: none; }
  .course { break-inside: avoid; }
  .session:nth-child(even) { background: none; }
}