/*
  DESIGN — Entwurf B „Tafelnacht" (von Elisa/Henry gewählt, 04.07.2026).
  Eine echte Kreidetafel bei Nacht: Tafelgrün statt Schwarz, Kreidestaub-Textur,
  zwei Kreidefarben (Gelb für Aroba, Staubrosa für „Revanche"), Nav-Symbole aus
  echten Mathe-Zeichen. Nimmt das Tafel-Motiv der künftigen Sprechstunde (Stufe 4)
  vorweg. Siehe code-tasks/lernplattform-FORTSCHRITT.md für den Design-Prozess.
*/

:root {
  --board: #1B2A22;
  --board-deep: #12201A;
  --board-raised: #223528;
  --chalk: #F1EFE6;
  --chalk-soft: #9FB3A5;
  --chalk-faint: #5C6F62;
  --accent: #F2C572;
  --accent-deep: #C79A44;
  --accent2: #E8998D;
  --rule: #34473C;
  --wash: rgba(242,197,114,0.10);
  --bad: #E8998D;

  --font-display: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Arial, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: ui-monospace, 'SF Mono', 'Cascadia Mono', Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background:
    radial-gradient(ellipse at 15% 0%, rgba(241,239,230,0.05), transparent 55%),
    radial-gradient(ellipse at 85% 85%, rgba(242,197,114,0.05), transparent 50%),
    var(--board);
  color: var(--chalk);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: '';
  position: fixed; inset: 0; pointer-events: none; z-index: 1;
  background-image:
    radial-gradient(rgba(241,239,230,0.045) 1px, transparent 1px),
    radial-gradient(rgba(241,239,230,0.03) 1px, transparent 1px);
  background-size: 3px 3px, 7px 7px;
  background-position: 0 0, 2px 4px;
  opacity: .5;
}

h1, h2, h3 { font-family: var(--font-display); font-weight: 700; text-wrap: balance; margin: 0; letter-spacing: .01em; }
p { margin: 0; }
button { font: inherit; }
::selection { background: var(--wash); color: var(--accent); }

a:focus-visible, button:focus-visible, input:focus-visible, .navlink:focus-visible {
  outline: 2.5px solid var(--accent);
  outline-offset: 2px;
  border-radius: 3px;
}

/* ── Login-Overlay ─────────────────────────────────────────────────────── */
#login {
  position: fixed; inset: 0; z-index: 50;
  display: flex; align-items: center; justify-content: center;
  background: var(--board-deep);
  padding: 24px;
}
#login.hidden { display: none; }
.login-card {
  width: min(380px, 100%);
  background: var(--board-raised);
  border: 1.5px dashed var(--rule);
  border-radius: 4px;
  padding: 36px 32px 30px;
  position: relative; z-index: 2;
}
.login-wordmark { display: flex; flex-direction: column; gap: 3px; margin-bottom: 28px; }
.login-wordmark .mark { font-size: 1.3rem; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; color: var(--accent); }
.login-wordmark .tag { font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; color: var(--chalk-faint); }
#course-tiles { display: flex; flex-direction: column; gap: 10px; margin-bottom: 22px; }
.course-tile {
  display: flex; align-items: center; gap: 14px;
  border: 1px solid var(--rule); border-radius: 3px;
  padding: 14px 16px;
  background: var(--board);
  cursor: pointer; text-align: left; width: 100%; color: inherit;
  transition: border-color .12s ease;
}
.course-tile:hover, .course-tile.selected { border-color: var(--accent); }
.course-avatar {
  width: 42px; height: 42px; border-radius: 50%;
  background: none; border: 1.5px solid var(--accent); color: var(--accent);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.1rem; font-weight: 800;
  flex-shrink: 0;
}
.course-tile .name { font-weight: 700; color: var(--chalk); }
.course-tile .sub { font-size: .8rem; color: var(--chalk-soft); }
label.field-label {
  display: block; font-size: .72rem; letter-spacing: .1em; text-transform: uppercase;
  color: var(--chalk-soft); margin-bottom: 8px;
}
.pin-row { display: flex; gap: 8px; margin-bottom: 10px; }
.pin-row input {
  width: 100%; text-align: center; font-family: var(--font-mono); font-size: 1.3rem;
  font-variant-numeric: tabular-nums;
  border: 1.5px solid var(--rule); border-radius: 3px; background: var(--board);
  color: var(--chalk); padding: 10px 0;
}
.pin-row input:focus { border-color: var(--accent); }
.login-error { min-height: 1.2em; font-size: .8rem; color: var(--bad); margin-bottom: 14px; }
.btn-primary {
  width: 100%; border: none; border-radius: 3px; padding: 12px 18px;
  background: var(--accent); color: #24270E; font-weight: 800; font-size: .9rem;
  letter-spacing: .04em; text-transform: uppercase;
  cursor: pointer; transition: background .15s ease, opacity .15s ease;
}
.btn-primary:hover { background: var(--accent-deep); }
.btn-primary:disabled { opacity: .55; cursor: default; }
.login-hint { margin-top: 16px; font-size: .76rem; color: var(--chalk-faint); text-align: center; }

/* ── App-Shell ─────────────────────────────────────────────────────────── */
#app { display: none; min-height: 100vh; grid-template-columns: 226px 1fr; position: relative; z-index: 2; }
#app.active { display: grid; }

aside.rail {
  background: var(--board-deep);
  border-right: 1.5px dashed var(--rule);
  padding: 26px 16px;
  display: flex; flex-direction: column; gap: 26px;
}
.rail-wordmark { display: flex; flex-direction: column; gap: 3px; padding: 0 8px; }
.rail-wordmark .mark { font-size: 1.1rem; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; color: var(--accent); }
.rail-wordmark .tag { font-size: .64rem; letter-spacing: .1em; text-transform: uppercase; color: var(--chalk-faint); }

nav.tabs { display: flex; flex-direction: column; gap: 4px; }
.navlink {
  display: flex; align-items: center; gap: 12px;
  padding: 10px 12px; border-radius: 3px; text-decoration: none;
  color: var(--chalk-soft); font-size: .87rem; font-weight: 600;
  letter-spacing: .02em;
  background: none; border: none; text-align: left; cursor: pointer;
  position: relative;
}
.navlink .glyph { font-family: var(--font-mono); font-size: 1.05rem; width: 20px; text-align: center; color: var(--chalk-faint); }
.navlink:hover { color: var(--chalk); }
.navlink.active { color: var(--accent); }
.navlink.active .glyph { color: var(--accent); }
.navlink.active::after {
  content: ''; position: absolute; left: 12px; right: 12px; bottom: 3px; height: 2px;
  background: var(--accent); opacity: .55; border-radius: 2px;
}
.navlink .soon { margin-left: auto; font-size: .6rem; letter-spacing: .05em; text-transform: uppercase; color: var(--board-deep); background: var(--chalk-faint); padding: 2px 6px; border-radius: 2px; }

.rail-foot { margin-top: auto; padding: 12px; border-top: 1.5px dashed var(--rule); display: flex; flex-direction: column; gap: 10px; }
.profile-chip { display: flex; align-items: center; gap: 10px; }
.profile-chip .av { width: 30px; height: 30px; border-radius: 50%; border: 1.5px solid var(--accent2); color: var(--accent2); display:flex; align-items:center; justify-content:center; font-size: .8rem; font-weight: 800; }
.profile-chip .who { font-size: .84rem; font-weight: 700; color: var(--chalk); }
.profile-chip .role { font-size: .7rem; color: var(--chalk-faint); }
.logout-link { background: none; border: none; color: var(--chalk-faint); font-size: .76rem; text-align: left; cursor: pointer; padding: 0; text-decoration: underline; text-underline-offset: 2px; }
.logout-link:hover { color: var(--chalk); }

main.stage { position: relative; }
.view { display: none; padding: 40px 56px 60px; max-width: min(1440px, 94vw); }
.view.active { display: block; }
/* Sprechstunde will die volle Breite für die 2D-Tafel-Fläche nutzen. */
#view-sprechstunde { max-width: none; }

.view-head { margin-bottom: 30px; }
.view-head h1 { font-size: 1.5rem; letter-spacing: .02em; }
.view-head .lede { color: var(--chalk-soft); font-size: .93rem; margin-top: 8px; max-width: 56ch; }

/* Start */
.tile-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.tile {
  background: var(--board-raised); border: 1.5px dashed var(--rule); border-radius: 4px;
  padding: 22px 22px 20px; cursor: pointer; text-align: left;
  transition: border-color .12s ease, transform .12s ease;
  display: flex; flex-direction: column; gap: 10px;
  color: inherit; font: inherit;
}
.tile:hover { border-color: var(--accent); transform: translateY(-2px); }
.tile .glyph { font-family: var(--font-mono); font-size: 1.5rem; color: var(--accent); }
.tile h3 { font-size: 1rem; letter-spacing: .02em; }
.tile p { color: var(--chalk-soft); font-size: .85rem; }
.tile.disabled { opacity: .5; cursor: default; }
.tile.disabled:hover { border-color: var(--rule); transform: none; }
.pill { display: inline-block; font-size: .62rem; letter-spacing: .06em; text-transform: uppercase; padding: 3px 8px; border-radius: 2px; background: var(--wash); color: var(--accent); width: fit-content; }

/* Lernen (Chat) */
.chat-shell { display: flex; flex-direction: column; height: calc(100vh - 190px); background: var(--board-raised); border: 1.5px dashed var(--rule); border-radius: 4px; overflow: hidden; position: relative; transition: border-color .12s ease, background .12s ease; }
.chat-shell.drag-over { border-color: var(--accent); background: var(--wash); }
.chat-shell.drag-over::after {
  content: 'Datei hier ablegen'; position: absolute; inset: 0; z-index: 5;
  display: flex; align-items: center; justify-content: center;
  font-size: 1rem; font-weight: 700; letter-spacing: .02em; color: var(--accent);
  background: rgba(18,32,26,0.55); pointer-events: none;
}
.chat-log { flex: 1; overflow-y: auto; padding: 26px 28px; display: flex; flex-direction: column; gap: 16px; }
.chat-empty { color: var(--chalk-faint); font-size: .88rem; text-align: center; margin-top: 40px; }
.msg { display: flex; gap: 12px; max-width: 74ch; }
.msg .av { width: 30px; height: 30px; border-radius: 50%; flex-shrink: 0; display: flex; align-items:center; justify-content:center; font-size: .8rem; font-weight: 800; border: 1.5px solid; }
.msg.aroba .av { border-color: var(--accent); color: var(--accent); }
.msg.me .av { border-color: var(--accent2); color: var(--accent2); }
.msg .bubble { border: 1px solid var(--rule); border-radius: 3px; padding: 12px 15px; font-size: .92rem; color: var(--chalk); background: var(--board); white-space: pre-wrap; }
.msg.me { align-self: flex-end; flex-direction: row-reverse; }
.msg.me .bubble { background: var(--board-deep); border-style: dashed; }
.msg.pending .bubble { color: var(--chalk-faint); font-style: italic; }
.msg .bubble strong.revanche { color: var(--accent2); letter-spacing: .02em; }
.chat-compose { display: flex; gap: 10px; padding: 14px 16px; border-top: 1.5px dashed var(--rule); background: var(--board-deep); }
.chat-compose input { flex: 1; border: 1.5px solid var(--rule); border-radius: 18px; padding: 10px 18px; font-size: .9rem; background: var(--board); color: var(--chalk); }
.chat-compose input::placeholder { color: var(--chalk-faint); }
.chat-compose input:focus { border-color: var(--accent); }
.icon-btn { width: 40px; height: 40px; border-radius: 50%; border: 1.5px solid var(--rule); background: var(--board); color: var(--chalk-soft); cursor: pointer; font-size: 1rem; flex-shrink:0; }
.icon-btn:hover { border-color: var(--accent); color: var(--accent); }
.send-btn { width: 40px; height: 40px; border-radius: 50%; border: none; background: var(--accent); color: #24270E; cursor: pointer; flex-shrink: 0; font-size: 1rem; font-weight: 800; }
.send-btn:hover { background: var(--accent-deep); }
.send-btn:disabled, .icon-btn:disabled { opacity: .5; cursor: default; }
.photo-preview { display: flex; align-items: center; gap: 8px; padding: 0 16px 10px; font-size: .78rem; color: var(--chalk-soft); }
.photo-preview button { background: none; border: none; color: var(--accent2); cursor: pointer; font-size: .78rem; text-decoration: underline; }

/* Lernsets */
.setform { display: flex; gap: 10px; margin-bottom: 26px; flex-wrap: wrap; }
.setform input { flex: 1; border: 1.5px solid var(--rule); border-radius: 3px; padding: 11px 14px; font-size: .92rem; background: var(--board-raised); color: var(--chalk); }
.setform input:focus { border-color: var(--accent); }
.setform button { border: none; border-radius: 3px; padding: 0 20px; background: var(--accent); color: #24270E; font-weight: 800; cursor: pointer; letter-spacing: .02em; text-transform: uppercase; font-size: .82rem; }
.setform button:hover { background: var(--accent-deep); }
.setform button:disabled { opacity: .55; cursor: default; }
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); gap: 14px; margin-bottom: 26px; }
.flashcard {
  position: relative; background: var(--board-raised); border: 1.5px dashed var(--rule); border-radius: 3px;
  padding: 16px 16px 18px; min-height: 108px; display: flex; flex-direction: column; justify-content: space-between;
}
.flashcard .term { font-weight: 700; font-size: .9rem; margin-bottom: 8px; color: var(--accent); letter-spacing: .01em; }
.flashcard .def { font-family: var(--font-mono); font-size: .8rem; color: var(--chalk-soft); font-variant-numeric: tabular-nums; }
.lernset-empty { color: var(--chalk-faint); font-size: .88rem; margin-bottom: 26px; }
.export-box { background: var(--board-raised); border: 1.5px dashed var(--rule); border-radius: 4px; padding: 18px 20px; display: none; }
.export-box.show { display: block; }
.export-box h3 { font-size: .88rem; margin-bottom: 10px; letter-spacing: .02em; }
.export-preview { font-family: var(--font-mono); font-size: .76rem; background: var(--board-deep); border: 1px solid var(--rule); border-radius: 3px; padding: 12px 14px; white-space: pre; overflow-x: auto; color: var(--chalk-soft); margin-bottom: 14px; }
.quizlet-btn { display: inline-flex; align-items: center; gap: 8px; border: none; border-radius: 3px; padding: 10px 18px; background: var(--accent2); color: #3A1712; font-weight: 800; cursor: pointer; font-size: .84rem; letter-spacing: .02em; text-transform: uppercase; }
.quizlet-btn:hover { filter: brightness(1.08); }
.copied-toast { margin-left: 12px; font-size: .8rem; color: var(--accent2); font-weight: 700; opacity: 0; transition: opacity .2s ease; }
.copied-toast.show { opacity: 1; }

/* Platzhalter (Sprechstunde/Archiv) */
.soon-panel {
  border: 1.5px dashed var(--rule); border-radius: 6px; padding: 48px 36px; text-align: center;
  display: flex; flex-direction: column; align-items: center; gap: 12px; max-width: 520px;
}
.soon-panel .glyph { font-family: var(--font-mono); font-size: 2.2rem; color: var(--accent); }
.soon-panel h3 { font-size: 1.1rem; letter-spacing: .02em; }
.soon-panel p { color: var(--chalk-soft); font-size: .88rem; max-width: 42ch; }

/* Sprechstunde (Stufe 4) */
.agenda-bar { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 16px; }
.agenda-item {
  font-size: .78rem; padding: 5px 12px; border-radius: 20px; border: 1.5px solid var(--rule);
  color: var(--chalk-faint); background: var(--board-raised); cursor: pointer;
}
.agenda-item:hover { border-color: var(--accent); color: var(--accent); }
.agenda-item.done { border-color: var(--chalk-faint); color: var(--chalk-soft); text-decoration: line-through; }
.agenda-item.active { border-color: var(--accent); color: var(--accent); font-weight: 700; cursor: default; }
.agenda-bar.busy .agenda-item { pointer-events: none; opacity: .6; }

.tafel-shell { display: flex; flex-direction: column; height: calc(100vh - 260px); background: var(--board-deep); border: 1.5px dashed var(--rule); border-radius: 4px; overflow: hidden; }

/* ── 2D-Tafel-Fläche (OneNote-artig, Henry-Wunsch 06.07.) ────────────────────
   .tafel-viewport ist der sichtbare, geclippte Ausschnitt; .tafel-world ist
   die (deutlich größere) pannbare/zoombare Ebene darin, auf der Karten frei
   nebeneinander/untereinander stehen können — sowohl Arobas Schritte als
   auch die Skizzen-Ebene sitzen als Kinder in .tafel-world und bewegen sich
   beim Pan/Zoom gemeinsam mit. */
.tafel-viewport { flex: 1; position: relative; overflow: hidden; background: var(--board); cursor: grab; touch-action: none; }
.tafel-viewport.panning { cursor: grabbing; }
.tafel-world { position: absolute; top: 0; left: 0; transform-origin: 0 0; will-change: transform; }

.tafel-card {
  position: absolute; width: 620px; max-width: 80vw; box-sizing: border-box;
  background: var(--board-raised); border: 1.5px dashed var(--rule); border-radius: 4px;
  padding: 0 20px 18px; z-index: 2;
}
.tafel-card.dragging { border-color: var(--accent); box-shadow: 0 6px 24px rgba(0,0,0,.35); z-index: 5; }
.tafel-card.tafel-note, .tafel-card.tafel-frage { width: 440px; }
.tafel-card-handle {
  margin: 0 -20px 14px; padding: 10px 20px; cursor: move; user-select: none;
  border-bottom: 1px dashed var(--rule); font-size: .68rem; letter-spacing: .06em;
  text-transform: uppercase; color: var(--chalk-faint);
}
.tafel-step { display: flex; flex-direction: column; gap: 10px; }
.tafel-sage { color: var(--chalk); font-size: .95rem; }
.tafel-el.tafel-heading h3 { color: var(--accent); font-size: 1.05rem; letter-spacing: .01em; margin: 0; }
.tafel-el.tafel-text { color: var(--chalk-soft); font-size: .9rem; }
.tafel-el.tafel-latex { color: var(--chalk); padding: 6px 0; overflow-x: auto; }
.tafel-el.tafel-table table { border-collapse: collapse; font-size: .85rem; }
.tafel-el.tafel-table th, .tafel-el.tafel-table td { border: 1px solid var(--rule); padding: 4px 10px; color: var(--chalk-soft); }
.tafel-el.tafel-table th { color: var(--accent); }
.jxg-box { width: min(100%, 480px); height: 320px; background: var(--board); border: 1px solid var(--rule); border-radius: 3px; }
.tafel-pending .tafel-sage { color: var(--chalk-faint); font-style: italic; }

/* Ephemere Hinweise (Warnungen/Agenda-Ende/Fehler) — NICHT Teil der Welt,
   da sie nie im Transcript persistiert werden (kein Sinn in einer festen
   Karten-Position). Fest über dem Viewport eingeblendet. */
.tafel-toast {
  position: absolute; left: 50%; top: 14px; transform: translateX(-50%); z-index: 8;
  max-width: min(560px, 88%); background: var(--board-deep); border: 1.5px dashed var(--rule);
  border-radius: 4px; padding: 10px 16px; font-size: .88rem; color: var(--chalk-soft);
  box-shadow: 0 6px 20px rgba(0,0,0,.35);
}

.tafel-controls { display: flex; gap: 8px; padding: 14px 16px; border-top: 1.5px dashed var(--rule); background: var(--board-deep); flex-wrap: wrap; }
.tafel-controls input { flex: 1; min-width: 160px; border: 1.5px solid var(--rule); border-radius: 18px; padding: 9px 16px; font-size: .88rem; background: var(--board); color: var(--chalk); }
.tafel-controls input::placeholder { color: var(--chalk-faint); }
.tafel-controls button { border: none; border-radius: 18px; padding: 9px 18px; font-weight: 700; font-size: .82rem; letter-spacing: .02em; text-transform: uppercase; cursor: pointer; background: var(--accent); color: #24270E; }
.tafel-controls button:hover { background: var(--accent-deep); }
.tafel-controls button:disabled { opacity: .5; cursor: default; }
.tafel-controls button.btn-ghost { background: none; border: 1.5px solid var(--rule); color: var(--chalk-soft); }
.tafel-controls button.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }

/* KaTeX/JSXGraph auf das Tafelnacht-Theme umgefärbt (lokal gebundelt, s. Dockerfile) */
.tafel-el .katex { color: var(--chalk); font-size: 1.05em; }
.jxg-box .JXGtext { color: var(--chalk) !important; }

/* Archiv (Stufe 3) */
.archiv-upload-row { display: flex; align-items: center; gap: 14px; margin-bottom: 8px; flex-wrap: wrap; }
.archiv-upload-row button {
  border: 1.5px dashed var(--rule); border-radius: 3px; padding: 9px 16px; background: var(--board-raised);
  color: var(--chalk); font-size: .85rem; cursor: pointer;
}
.archiv-upload-row button:hover { border-color: var(--accent); color: var(--accent); }
.archiv-upload-row button:disabled { opacity: .5; cursor: default; }
.archiv-upload-check { display: flex; align-items: center; gap: 6px; font-size: .8rem; color: var(--chalk-soft); }
.archiv-upload-status { font-size: .82rem; color: var(--chalk-soft); min-height: 1.4em; margin-bottom: 18px; }
.archiv-subhead { font-size: .85rem; letter-spacing: .04em; text-transform: uppercase; color: var(--chalk-soft); margin: 26px 0 12px; }
.archiv-item, .archiv-hit {
  border: 1.5px dashed var(--rule); border-radius: 3px; background: var(--board-raised);
  padding: 12px 16px; margin-bottom: 10px;
}
.archiv-item .title, .archiv-hit .title { font-weight: 700; font-size: .9rem; color: var(--accent); margin-bottom: 4px; }
.archiv-item .meta { font-size: .76rem; color: var(--chalk-faint); display: flex; gap: 10px; flex-wrap: wrap; }
.archiv-item .meta span { background: var(--wash); padding: 1px 7px; border-radius: 2px; }
.archiv-hit .snippet { font-size: .82rem; color: var(--chalk-soft); }

@media (max-width: 760px) {
  #app.active { display: flex; flex-direction: column; }
  aside.rail { flex-direction: row; align-items: center; padding: 12px 14px; overflow-x: auto; gap: 14px; border-right: none; border-bottom: 1.5px dashed var(--rule); }
  .rail-wordmark { display: none; }
  nav.tabs { flex-direction: row; gap: 4px; }
  .navlink span.label { display: none; }
  .navlink { padding: 9px 11px; }
  .navlink.active::after { left: 8px; right: 8px; }
  .rail-foot { margin-top: 0; margin-left: auto; border-top: none; padding: 0; flex-direction: row; align-items: center; }
  .logout-link { display: none; }
  .view { padding: 26px 18px 50px; }
  .tile-grid { grid-template-columns: 1fr; }
  .chat-shell { height: calc(100vh - 230px); }
  .tafel-shell { height: calc(100vh - 230px); }
}

/* ── Geräte-Umschalter (rail-foot) ────────────────────────────────────────── */
.device-toggle { display: flex; gap: 4px; margin-bottom: 4px; }
.device-btn {
  flex: 1; border: 1.5px solid var(--rule); background: none; color: var(--chalk-faint);
  border-radius: 14px; padding: 5px 8px; font-size: .72rem; font-weight: 700;
  letter-spacing: .02em; cursor: pointer;
}
.device-btn:hover { border-color: var(--accent); color: var(--accent); }
.device-btn.active { border-color: var(--accent); color: var(--accent); background: var(--wash); }

/* ── Geräte-Override: gewinnt per Attribut-Spezifität gegen die reine
   @media-Regel oben, ohne sie zu ersetzen (JS-loses Sicherheitsnetz bleibt). ── */
html[data-device="mobile"] #app.active { display: flex; flex-direction: column; }
html[data-device="mobile"] aside.rail { flex-direction: row; align-items: center; padding: 12px 14px; overflow-x: auto; gap: 14px; border-right: none; border-bottom: 1.5px dashed var(--rule); }
html[data-device="mobile"] .rail-wordmark { display: none; }
html[data-device="mobile"] nav.tabs { flex-direction: row; gap: 4px; }
html[data-device="mobile"] .navlink span.label { display: none; }
html[data-device="mobile"] .navlink { padding: 9px 11px; }
html[data-device="mobile"] .navlink.active::after { left: 8px; right: 8px; }
html[data-device="mobile"] .rail-foot { margin-top: 0; margin-left: auto; border-top: none; padding: 0; flex-direction: row; align-items: center; }
html[data-device="mobile"] .logout-link { display: none; }
html[data-device="mobile"] .device-toggle { margin-bottom: 0; }
html[data-device="mobile"] .view { padding: 26px 18px 50px; }
html[data-device="mobile"] .tile-grid { grid-template-columns: 1fr; }
html[data-device="mobile"] .chat-shell { height: calc(100vh - 230px); }
html[data-device="mobile"] .tafel-shell { height: calc(100vh - 230px); }

html[data-device="desktop"] #app.active { display: grid; }
html[data-device="desktop"] aside.rail { flex-direction: column; align-items: stretch; padding: 26px 16px; overflow-x: visible; gap: 26px; border-right: 1.5px dashed var(--rule); border-bottom: none; }
html[data-device="desktop"] .rail-wordmark { display: flex; }
html[data-device="desktop"] nav.tabs { flex-direction: column; gap: 4px; }
html[data-device="desktop"] .navlink span.label { display: inline; }
html[data-device="desktop"] .rail-foot { margin-top: auto; margin-left: 0; border-top: 1.5px dashed var(--rule); padding: 12px; flex-direction: column; align-items: stretch; }
html[data-device="desktop"] .logout-link { display: block; }
html[data-device="desktop"] .view { padding: 48px 64px 70px; max-width: min(1440px, 94vw); }
html[data-device="desktop"] .tile-grid { grid-template-columns: repeat(2, 1fr); }
html[data-device="desktop"] .chat-shell { height: calc(100vh - 190px); }
html[data-device="desktop"] .tafel-shell { height: calc(100vh - 260px); }

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
  .dots span { opacity: .7; } /* Punkte bleiben als statisches „dran"-Zeichen sichtbar */
}

/* ── Sprechstunde: Pause/Fortsetzen ──────────────────────────────────────── */
.resume-card {
  display: flex; align-items: center; justify-content: space-between; gap: 14px; flex-wrap: wrap;
  border: 1.5px dashed var(--accent); border-radius: 4px; background: var(--wash);
  padding: 14px 18px; margin-bottom: 18px; color: var(--chalk); font-size: .92rem;
}
.resume-card .resume-text strong { color: var(--accent); }
.resume-card button {
  border: none; border-radius: 18px; padding: 9px 18px; font-weight: 700; font-size: .82rem;
  letter-spacing: .02em; text-transform: uppercase; cursor: pointer;
  background: var(--accent); color: #24270E;
}
.resume-card button:hover { background: var(--accent-deep); }
.form-hint { font-size: .8rem; color: var(--chalk-faint); margin-top: 10px; }

/* ── Sprechstunde: Zeichnen auf der Tafel ────────────────────────────────── */
#tafel-sketch {
  position: absolute; top: 0; left: 0; z-index: 1;
  pointer-events: none; /* nur im Zeichnen-Modus fängt das Canvas Eingaben ab */
}
#tafel-sketch.drawing { pointer-events: auto; cursor: crosshair; touch-action: none; }
.tafel-toolbar {
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  padding: 10px 16px; border-bottom: 1.5px dashed var(--rule); background: var(--board-deep);
}
.toolbar-label { font-size: .72rem; color: var(--chalk-soft); text-transform: uppercase; letter-spacing: .06em; }
.toolbar-spacer { flex: 1; }
.chalk-btn {
  width: 26px; height: 26px; border-radius: 50%; cursor: pointer;
  background: var(--c); border: 2px solid transparent; padding: 0;
}
.chalk-btn.active { border-color: var(--accent); box-shadow: 0 0 0 2.5px var(--board); }
.tool-btn {
  border: 1.5px solid var(--rule); background: none; color: var(--chalk-soft);
  border-radius: 14px; padding: 5px 12px; font-size: .78rem; cursor: pointer;
}
.tool-btn:hover { border-color: var(--accent); color: var(--accent); }
.tool-btn.active { border-color: var(--accent); color: var(--accent); }
.tool-btn.tool-send { border-color: var(--accent); color: var(--accent); font-weight: 700; }
.tool-btn:disabled { opacity: .5; cursor: default; }
.tafel-controls button.btn-ghost.active { border-color: var(--accent); color: var(--accent); }

/* ── Lern-Sitzungen: Neu-Button + Fortsetzen-Chips (05.07.) ─────────────────── */
.sitzung-bar { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-bottom: 10px; }
.sitzung-chip {
  font-size: .8rem; font-weight: 700; color: var(--accent); background: var(--wash);
  border: 1.5px dashed var(--accent); border-radius: 20px; padding: 5px 14px;
  max-width: 40ch; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.sitzung-neu-btn {
  border: 1.5px solid var(--rule); background: none; color: var(--chalk-soft);
  border-radius: 20px; padding: 5px 14px; font-size: .8rem; font-weight: 700; cursor: pointer;
}
.sitzung-neu-btn:hover { border-color: var(--accent); color: var(--accent); }
.sitzung-liste { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.sitzung-item {
  border: 1.5px dashed var(--rule); background: var(--board-raised); color: var(--chalk-soft);
  border-radius: 20px; padding: 4px 12px; font-size: .76rem; cursor: pointer;
  max-width: 32ch; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.sitzung-item:hover { border-color: var(--accent); color: var(--accent); }
#lernset-liste { margin-bottom: 14px; }
.sitzung-neu-form { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 12px; }
.sitzung-neu-form input {
  border: 1.5px solid var(--rule); border-radius: 18px; padding: 8px 14px; font-size: .86rem;
  background: var(--board); color: var(--chalk); min-width: 150px;
}
.sitzung-neu-form input::placeholder { color: var(--chalk-faint); }
.sitzung-neu-form button {
  border: none; border-radius: 18px; padding: 8px 16px; font-weight: 700; font-size: .8rem;
  letter-spacing: .02em; text-transform: uppercase; cursor: pointer; background: var(--accent); color: #24270E;
}
.sitzung-neu-form button:hover { background: var(--accent-deep); }
.sitzung-neu-form button.btn-cancel { background: none; border: 1.5px solid var(--rule); color: var(--chalk-soft); }
.sitzung-neu-form button.btn-cancel:hover { border-color: var(--accent); color: var(--accent); }
.setform input.fach-input { flex: 0 1 200px; min-width: 140px; }

/* ── „Aroba ist dran"-Anzeige: pulsierende Kreidepunkte bei LLM-Wartezeiten ── */
.dots { display: inline-flex; gap: 4px; margin-left: 8px; vertical-align: middle; }
.dots span {
  width: 5px; height: 5px; border-radius: 50%; background: currentColor;
  opacity: .25; animation: dotpulse 1.2s ease-in-out infinite;
}
.dots span:nth-child(2) { animation-delay: .2s; }
.dots span:nth-child(3) { animation-delay: .4s; }
@keyframes dotpulse { 0%, 80%, 100% { opacity: .25; } 40% { opacity: 1; } }
.start-status { display: flex; align-items: center; margin-top: 12px; font-size: .88rem; color: var(--chalk-soft); }

/* ── Archiv: Drag & Drop + Mehrfach-Upload ───────────────────────────────── */
#view-archiv { position: relative; }
#view-archiv.drop-over::after {
  content: 'Dateien hier ablegen — sie landen im Kurs-Archiv';
  position: absolute; inset: 10px; z-index: 8;
  display: flex; align-items: center; justify-content: center; text-align: center;
  font-size: 1rem; font-weight: 700; letter-spacing: .02em; color: var(--accent);
  background: rgba(18,32,26,0.8); border: 2px dashed var(--accent); border-radius: 6px;
  pointer-events: none;
}
.archiv-upload-hint { font-size: .78rem; color: var(--chalk-faint); }