/* ═══════════════════════════════════════════════════════════════
   ARCHe runtime CSS — base styles, calculator, LiveSession
   Generated by build-runtime.py — do not edit by hand.
   ═══════════════════════════════════════════════════════════════ */

/* === Base styles ===================================================== */
:root {
  --bg:       #0a0e1a;
  --bg-elev:  #141826;
  --bg-card:  #171c2e;
  --ink:      #d9cfb8;
  --txt:      #d9cfb8;
  --muted:    #7a8094;
  --brass:    #e8b830;
  --brass-l:  #f0cf5f;
  --brass-d:  #9c7a14;
  --rose:     #e88fb5;
  --sky:      #6bc4f5;
  --green:    #5ec28e;
  --red:      #f06969;
  --bdr:      #2a3247;
  --bdr-l:    #3a4668;
  --shadow-d: rgba(0,0,0,0.6);
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: 'EB Garamond', Georgia, serif;
  font-size: 17px;
  line-height: 1.5;
  min-height: 100vh;
  background-image:
    radial-gradient(ellipse at top, rgba(232,184,48,0.04) 0%, transparent 60%),
    radial-gradient(ellipse at bottom right, rgba(232,143,181,0.03) 0%, transparent 50%);
}
.disp, h1, h2, h3 {
  font-family: 'Cinzel Decorative', 'Cinzel', Georgia, serif;
  letter-spacing: 0.03em;
  color: var(--brass-l);
  font-weight: 500;
}
h1 { font-size: 2.2rem; margin: 0 0 12px; }
h2 { font-size: 1.5rem; margin: 18px 0 10px; }
h3 { font-size: 1.15rem; margin: 14px 0 8px; color: var(--brass); }
p { margin: 8px 0; }
.mono { font-family: 'IBM Plex Mono', monospace; }
.muted { color: var(--muted); }
.highlight { color: var(--brass-l); font-weight: 500; }
.eq-inline {
  font-family: 'IBM Plex Mono', monospace;
  color: var(--brass-l);
  background: rgba(232,184,48,0.08);
  padding: 1px 6px;
  border-radius: 3px;
  font-size: 0.95em;
}

.frac {
  display: inline-flex;
  flex-direction: column;
  vertical-align: -0.45em;
  text-align: center;
  margin: 0 0.15em;
  line-height: 1.05;
  font-size: 0.95em;
}
.frac > .num {
  border-bottom: 1px solid currentColor;
  padding: 0 0.3em 0.05em;
  display: block;
}
.frac > .den {
  padding: 0.05em 0.3em 0;
  display: block;
}
.screen { display: none; min-height: 100vh; padding: 24px 16px 80px; }
.screen.active { display: block; }
.wrap { max-width: 860px; margin: 0 auto; }

.home-header {
  text-align: center;
  padding: 36px 16px 28px;
  border-bottom: 1px solid var(--bdr);
  margin-bottom: 36px;
}
.home-header h1 { font-family: 'Cinzel Decorative', serif; font-size: 2.2rem; margin-bottom: 6px; }
.home-header .kicker {
  font-family: 'Cinzel', serif;
  font-size: 0.8rem;
  letter-spacing: 0.3em;
  color: var(--brass-d);
  text-transform: uppercase;
  margin-bottom: 12px;
}
.home-header .subtitle { color: var(--muted); font-style: italic; font-size: 1.05rem; }
.home-header .meta {
  margin-top: 20px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.82rem;
  color: var(--muted);
  letter-spacing: 0.08em;
}
.home-header .meta b { color: var(--brass); font-weight: 600; }

.atom-index { max-width: 820px; margin: 0 auto; }
.atom-index h2 {
  font-family: 'Cinzel', serif;
  font-size: 0.85rem;
  letter-spacing: 0.24em;
  color: var(--muted);
  text-transform: uppercase;
  text-align: center;
  margin: 32px 0 14px;
  font-weight: 500;
}

/* ─── Question-group header ───────────────────────────── */
.qgroup {
  margin-bottom: 22px;
  border: 1px solid var(--bdr);
  border-radius: 8px;
  background: rgba(20,24,38,0.45);
  overflow: hidden;
}
.qgroup-head {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  cursor: pointer;
  background: linear-gradient(180deg, rgba(232,184,48,0.08), transparent);
  border-bottom: 1px solid var(--bdr);
  transition: background 0.15s;
}
.qgroup-head:hover { background: linear-gradient(180deg, rgba(232,184,48,0.14), transparent); }
.qgroup-head .q-num {
  font-family: 'Cinzel Decorative', serif;
  color: var(--brass);
  font-size: 1.1rem;
  letter-spacing: 0.12em;
  flex-shrink: 0;
  min-width: 40px;
}
.qgroup-head .q-title {
  flex: 1;
  font-family: 'Cinzel', serif;
  color: var(--brass-l);
  font-size: 1.02rem;
  letter-spacing: 0.02em;
}
.qgroup-head .q-marks {
  font-family: 'IBM Plex Mono', monospace;
  color: var(--muted);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  margin-right: 8px;
}
.qgroup-head .q-prog {
  font-family: 'IBM Plex Mono', monospace;
  color: var(--brass-d);
  font-size: 0.82rem;
  flex-shrink: 0;
}
.qgroup-head .q-prog.done { color: var(--green); }
.qgroup-head .q-caret {
  font-family: monospace;
  color: var(--muted);
  font-size: 1rem;
  transition: transform 0.2s;
}
.qgroup.open .q-caret { transform: rotate(90deg); }
.qgroup-body { display: none; padding: 6px 10px 10px; }
.qgroup.open .qgroup-body { display: block; }

.atom-tile {
  background: var(--bg-card);
  border: 1px solid var(--bdr);
  border-radius: 6px;
  padding: 10px 14px;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  transition: all 0.16s;
}
.atom-tile:hover {
  border-color: var(--brass-d);
  transform: translateX(2px);
}
.atom-tile .atom-idx {
  font-family: 'Cinzel Decorative', serif;
  color: var(--brass-d);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  flex-shrink: 0;
  min-width: 36px;
}
.atom-tile .atom-body { flex: 1; min-width: 0; }
.atom-tile .atom-title {
  color: var(--brass-l);
  font-family: 'Cinzel', serif;
  font-size: 0.96rem;
  margin-bottom: 0;
}
.atom-tile .atom-prog {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.78rem;
  color: var(--brass-d);
  flex-shrink: 0;
}
.atom-tile .atom-prog.done { color: var(--green); }
.atom-tile.capstone {
  background: linear-gradient(180deg, rgba(232,184,48,0.07), rgba(232,184,48,0.02));
  border-color: var(--brass-d);
}
.atom-tile.capstone .atom-title { color: var(--brass); font-weight: 600; }

.begin-bar { text-align: center; margin: 28px 0 12px; }
.btn {
  font-family: 'Cinzel', serif;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  padding: 10px 22px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.88rem;
  transition: all 0.15s;
  background: transparent;
  border: 1px solid var(--bdr-l);
  color: var(--ink);
}
.btn.primary {
  background: linear-gradient(180deg, rgba(232,184,48,0.18), rgba(232,184,48,0.08));
  border-color: var(--brass);
  color: var(--brass-l);
}
.btn.primary:hover {
  background: linear-gradient(180deg, rgba(232,184,48,0.28), rgba(232,184,48,0.12));
  box-shadow: 0 0 14px rgba(232,184,48,0.2);
}
.btn:hover { border-color: var(--brass-d); color: var(--brass-l); }
.btn:disabled { opacity: 0.35; cursor: not-allowed; }

.atom-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  font-family: 'Cinzel', serif;
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
}
.atom-header a {
  color: var(--muted);
  text-decoration: none;
  cursor: pointer;
  transition: color 0.15s;
}
.atom-header a:hover { color: var(--brass-l); }

.atom-title-block {
  text-align: center;
  margin-bottom: 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--bdr);
}
.atom-title-block h2 {
  font-family: 'Cinzel Decorative', serif;
  font-size: 1.45rem;
  margin: 0 0 4px;
}
.atom-title-block .atom-ref {
  color: var(--muted);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.82rem;
}

.teaching {
  background: rgba(20,24,38,0.7);
  border-left: 3px solid var(--brass-d);
  padding: 14px 18px;
  margin-bottom: 18px;
  border-radius: 4px;
}
.teaching p:first-child { margin-top: 4px; }
.teaching p:last-child  { margin-bottom: 4px; }

.rule-box {
  background: rgba(232,184,48,0.06);
  border: 1px solid rgba(232,184,48,0.2);
  border-radius: 4px;
  padding: 10px 14px;
  margin: 12px 0;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.93rem;
  line-height: 1.55;
}
.rule-box b { color: var(--brass-l); }

.progress-bar-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: 'Cinzel', serif;
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--muted);
  text-transform: uppercase;
  margin-bottom: 18px;
}
.progress-bar {
  flex: 1; height: 6px;
  background: var(--bg-elev);
  border-radius: 3px;
  overflow: hidden;
  border: 1px solid var(--bdr);
}
.progress-bar .fill {
  height: 100%;
  background: linear-gradient(to right, var(--brass), var(--brass-l));
  transition: width 0.4s ease-out;
}

.prompt {
  background: rgba(23,28,46,0.55);
  border: 1px solid var(--bdr);
  padding: 14px 18px;
  border-radius: 4px;
  margin-bottom: 14px;
  font-size: 1.04rem;
  line-height: 1.55;
}

/* Diagram container on the atom screen — sits between prompt and answer.
   Inherits currentColor from the page so the diagram primitives pick up
   the theme automatically. */
.a-diagram {
  margin: 8px 0 14px;
  padding: 12px;
  background: rgba(23,28,46,0.35);
  border: 1px solid var(--bdr);
  border-radius: 4px;
  text-align: center;
  color: var(--ink);
}
.a-diagram svg.diagram {
  display: inline-block;
  max-width: 100%;
  height: auto;
}
.a-diagram .diagram-error {
  color: #c44;
}

.hintbox {
  background: rgba(107,196,245,0.08);
  border-left: 3px solid var(--sky);
  padding: 10px 14px;
  margin-bottom: 14px;
  border-radius: 4px;
  font-size: 0.94rem;
  color: #b8d9f3;
}
.hintbox .hl { color: var(--brass-l); font-family: 'IBM Plex Mono', monospace; }

.answer-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 14px;
}
.answer-row .label {
  font-family: 'Cinzel', serif;
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  color: var(--muted);
  text-transform: uppercase;
}
.answer-row input[type="text"] {
  background: var(--bg-elev);
  border: 1px solid var(--bdr-l);
  color: var(--brass-l);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 1.1rem;
  padding: 8px 12px;
  border-radius: 4px;
  width: 180px;
  letter-spacing: 0.04em;
  text-align: center;
  outline: none;
  transition: border-color 0.15s;
}
.answer-row input[type="text"]:focus { border-color: var(--brass); }
.answer-row input.correct { border-color: var(--green); color: var(--green); }
.answer-row input.wrong   { border-color: var(--red); color: var(--red); }

.status-line {
  min-height: 24px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.9rem;
  margin: 4px 0 12px;
}
.status-line.correct { color: var(--green); }
.status-line.wrong   { color: var(--red); }
.status-line.info    { color: var(--sky); }

.controls { display: flex; gap: 10px; justify-content: flex-end; flex-wrap: wrap; }

.done-card {
  background: var(--bg-card);
  border: 1px solid var(--brass-d);
  border-radius: 8px;
  padding: 28px 26px;
  text-align: center;
  margin-top: 28px;
}
.done-card h2 { color: var(--brass-l); }
.done-card .stat {
  font-family: 'Cinzel Decorative', serif;
  font-size: 1.4rem;
  color: var(--brass);
  margin: 10px 0;
}

.footer-nav {
  text-align: center;
  margin-top: 28px;
  color: var(--muted);
  font-size: 0.78rem;
  font-family: 'IBM Plex Mono', monospace;
  letter-spacing: 0.12em;
}

.teacher-skip-row {
  display: none;
  justify-content: flex-end;
  gap: 10px;
  margin: -4px 0 14px;
  padding: 6px 0;
  border-top: 1px dashed var(--bdr-l);
  border-bottom: 1px dashed var(--bdr-l);
}
.teacher-skip-row.on { display: flex; }
.btn-skip {
  background: transparent;
  border: 1px dashed var(--muted);
  color: var(--muted);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.78rem;
  letter-spacing: 0.05em;
  padding: 6px 12px;
  border-radius: 4px;
  cursor: pointer;
  text-transform: uppercase;
}
.btn-skip:hover { border-color: var(--brass); color: var(--brass-l); background: rgba(232,184,48,0.08); }
.btn-skip.home { border-color: var(--rose); color: var(--rose); }
.btn-skip.home:hover { background: rgba(232,143,181,0.08); }

/* === Calculator widget =============================================== */
  #calc-fab {
    position: fixed; bottom: 18px; right: 18px;
    width: 56px; height: 56px; border-radius: 50%;
    background: linear-gradient(135deg, var(--brass) 0%, var(--brass-d) 100%);
    color: var(--bg);
    display: flex; align-items: center; justify-content: center;
    box-shadow: 0 4px 16px rgba(0,0,0,0.55), 0 0 0 1px var(--brass-d);
    cursor: pointer; z-index: 9000; user-select: none;
    transition: transform 0.15s ease;
    font-family: 'Cinzel', serif; font-weight: 700; font-size: 26px;
    -webkit-tap-highlight-color: transparent;
  }
  #calc-fab:hover { transform: scale(1.06); }
  #calc-fab:active { transform: scale(0.95); }
  #calc-panel {
    position: fixed; bottom: 86px; right: 18px;
    width: 320px; max-width: calc(100vw - 24px);
    background: var(--bg-elev);
    border: 1px solid var(--brass-d);
    border-radius: 10px;
    box-shadow: 0 12px 36px rgba(0,0,0,0.7);
    z-index: 9001;
    font-family: 'IBM Plex Mono', monospace;
    overflow: hidden;
    display: flex; flex-direction: column;
    transition: opacity 0.18s ease, transform 0.18s ease;
  }
  #calc-panel.calc-collapsed {
    opacity: 0;
    transform: translateY(16px) scale(0.95);
    pointer-events: none;
  }
  .calc-header {
    display: flex; align-items: center; gap: 8px;
    padding: 8px 12px;
    background: var(--bg-card);
    border-bottom: 1px solid var(--bdr);
  }
  .calc-mode-pill {
    background: var(--brass-d); color: var(--bg);
    font-size: 10px; padding: 2px 7px; border-radius: 3px;
    font-weight: 700; letter-spacing: 0.05em;
  }
  .calc-title {
    flex: 1;
    font-family: 'Cinzel', serif; font-weight: 600;
    color: var(--brass);
    letter-spacing: 0.08em; font-size: 12px; text-transform: uppercase;
  }
  .calc-close {
    background: transparent; border: none;
    color: var(--muted); font-size: 22px;
    cursor: pointer; padding: 0; line-height: 1;
    width: 24px; height: 24px;
  }
  .calc-close:hover { color: var(--rose); }
  .calc-display {
    background: #06080f;
    padding: 12px 14px;
    text-align: right;
    border-bottom: 1px solid var(--bdr);
    min-height: 64px;
    user-select: text;
    -webkit-user-select: text;
  }
  .calc-history {
    font-size: 11px; color: var(--muted);
    height: 14px; overflow: hidden;
    margin-bottom: 4px;
  }
  .calc-screen {
    font-size: 22px; color: var(--ink);
    overflow-x: auto; overflow-y: hidden; white-space: nowrap;
    min-height: 28px;
  }
  .calc-screen::-webkit-scrollbar { height: 4px; }
  .calc-screen::-webkit-scrollbar-thumb { background: var(--bdr); }
  .calc-buttons {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 4px; padding: 8px;
  }
  .calc-buttons button {
    background: var(--bg-card); color: var(--ink);
    border: 1px solid var(--bdr);
    padding: 9px 2px;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 13px; font-weight: 500;
    cursor: pointer; border-radius: 4px;
    transition: all 0.07s ease;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
  }
  .calc-buttons button:hover {
    background: var(--bdr);
    border-color: var(--brass-d);
  }
  .calc-buttons button:active {
    transform: scale(0.96);
    background: var(--brass-d);
    color: var(--bg);
  }
  .calc-buttons button.fn { color: var(--sky); font-size: 11px; }
  .calc-buttons button.op { color: var(--brass); font-size: 14px; font-weight: 600; }
  .calc-buttons button.ctl { color: var(--rose); font-size: 12px; }
  .calc-buttons button.adv { color: var(--brass-l); font-size: 11px; font-weight: 600; }
  .calc-buttons button.eq {
    background: linear-gradient(135deg, var(--brass) 0%, var(--brass-d) 100%);
    color: var(--bg); font-weight: 700; font-size: 16px;
    border-color: var(--brass-d);
  }
  .calc-buttons button.eq:hover { background: var(--brass-l); }
  .calc-buttons button.span2 { grid-column: span 2; }
  .calc-buttons button.span3 { grid-column: span 3; }

  /* Advanced form overlay (d/dx and ∫) */
  .calc-form {
    padding: 12px;
    background: var(--bg-elev);
    display: none;
  }
  .calc-form.on { display: block; }
  .calc-form-title {
    font-family: 'Cinzel', serif; font-weight: 600;
    color: var(--brass);
    text-transform: uppercase; letter-spacing: 0.08em;
    font-size: 12px; margin-bottom: 8px; text-align: center;
  }
  .calc-form-row {
    display: flex; align-items: center; gap: 8px;
    margin-bottom: 8px;
  }
  .calc-form-row label {
    color: var(--muted); font-size: 12px; min-width: 60px;
  }
  .calc-form-row input {
    flex: 1; background: #06080f;
    border: 1px solid var(--bdr); color: var(--ink);
    padding: 6px 8px; border-radius: 4px;
    font-family: 'IBM Plex Mono', monospace; font-size: 13px;
    outline: none;
  }
  .calc-form-row input:focus { border-color: var(--brass-d); }
  .calc-form-actions {
    display: flex; gap: 6px; margin-top: 10px;
  }
  .calc-form-actions button {
    flex: 1; padding: 8px;
    background: var(--bg-card); color: var(--ink);
    border: 1px solid var(--bdr); border-radius: 4px;
    cursor: pointer;
    font-family: 'IBM Plex Mono', monospace; font-size: 12px;
  }
  .calc-form-actions button.primary {
    background: linear-gradient(135deg, var(--brass) 0%, var(--brass-d) 100%);
    color: var(--bg); font-weight: 600; border-color: var(--brass-d);
  }
  .calc-form-hint {
    font-size: 10px; color: var(--muted);
    margin-top: 6px; line-height: 1.4;
  }

  @media (max-width: 480px) {
    #calc-panel { width: calc(100vw - 24px); right: 12px; bottom: 80px; }
    #calc-fab { bottom: 14px; right: 14px; }
  }

/* === LiveSession ===================================================== */
/* ════════════════════════════════════════════════════════════════════
   LIVE SESSION — shared CSS
   Dark academia palette matching existing apps.  Scoped with `ls-`
   class prefix so nothing collides with per-app styles.
   ════════════════════════════════════════════════════════════════════ */

/* ─── Login screen ──────────────────────────────────────────── */
#ls-screen-login {
  position: fixed; inset: 0;
  background: linear-gradient(180deg, #0a0e1a 0%, #0f1220 100%);
  color: #e4dfd0;
  font-family: 'EB Garamond', Georgia, serif;
  display: flex; align-items: center; justify-content: center;
  padding: 20px; z-index: 9000;
}
#ls-screen-login.hidden { display: none; }

#ls-screen-login .ls-lbox {
  background: rgba(20, 24, 42, 0.82);
  border: 1.5px solid #2a2e44;
  border-radius: 14px;
  padding: 36px 32px 28px;
  max-width: 520px; width: 100%;
  box-shadow: 0 30px 80px rgba(0,0,0,0.45);
}

#ls-screen-login .ls-brand {
  font-family: 'Cinzel', serif;
  font-size: 0.74rem;
  letter-spacing: 0.22em;
  color: #c9941a;
  text-transform: uppercase;
  display: block;
  margin-bottom: 6px;
}
#ls-screen-login h1 {
  font-family: 'Cinzel', serif;
  color: #e8b830;
  font-size: 1.9rem;
  line-height: 1.15;
  margin: 0 0 22px;
  font-weight: 500;
}

#ls-screen-login .ls-tabs {
  display: flex; gap: 4px;
  background: rgba(10,14,26,0.5);
  padding: 4px; border-radius: 10px;
  margin-bottom: 20px;
}
#ls-screen-login .ls-tab {
  flex: 1; padding: 10px 14px;
  background: transparent; color: #a9a499;
  border: none; border-radius: 7px;
  font-family: inherit; font-size: 0.95rem;
  cursor: pointer; transition: all 0.2s;
}
#ls-screen-login .ls-tab.active {
  background: rgba(232,184,48,0.15);
  color: #e8b830;
  font-weight: 600;
}
#ls-screen-login .ls-panel { display: block; }
#ls-screen-login .ls-panel.hidden { display: none; }

#ls-screen-login .ls-desc {
  color: #a9a499;
  font-size: 0.98rem;
  margin: 0 0 16px;
  line-height: 1.45;
}
#ls-screen-login .ls-label {
  display: block;
  font-family: 'Cinzel', serif;
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: #a9a499;
  margin-top: 12px;
  margin-bottom: 6px;
  text-transform: uppercase;
}
#ls-screen-login .ls-input {
  width: 100%;
  background: rgba(10,14,26,0.7);
  border: 1.5px solid #3a3e54;
  border-radius: 7px;
  color: #e4dfd0;
  padding: 11px 14px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 1.05rem;
  outline: none;
  box-sizing: border-box;
}
#ls-screen-login .ls-input:focus { border-color: #e8b830; }
#ls-screen-login .ls-input.ls-name-input { text-transform: none; font-family: inherit; }
#ls-screen-login .ls-input.ls-code-input { text-transform: uppercase; letter-spacing: 0.15em; font-weight: 600; }

#ls-screen-login .ls-hint {
  color: #7a7a7a;
  font-size: 0.82rem;
  margin: 8px 0 0;
  line-height: 1.5;
}

#ls-screen-login .ls-btn {
  background: #e8b830; color: #1a1e2e;
  border: none; border-radius: 7px;
  padding: 12px 20px; font-size: 1rem; font-weight: 600;
  cursor: pointer; font-family: inherit;
  transition: background 0.2s;
}
#ls-screen-login .ls-btn:hover { background: #d4a020; }
#ls-screen-login .ls-btn-ghost {
  background: transparent;
  color: #e8b830;
  border: 1.5px solid #c9941a;
}
#ls-screen-login .ls-btn-ghost:hover { background: rgba(232,184,48,0.08); }
#ls-screen-login .ls-btn-block { width: 100%; margin-top: 14px; }

#ls-screen-login .ls-t-sec {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid #2a2e44;
}
#ls-screen-login .ls-t-sec-ttl {
  font-family: 'Cinzel', serif;
  font-size: 0.82rem;
  color: #e8b830;
  letter-spacing: 0.08em;
  margin-bottom: 10px;
}

#ls-screen-login .ls-err {
  color: #f87171;
  font-size: 0.9rem;
  margin-top: 14px;
  min-height: 1.2em;
  text-align: center;
}

#ls-screen-login .ls-env-banner {
  text-align: center;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  color: #7a7a7a;
  margin-top: 16px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* PIN dialog */
#ls-pin-overlay {
  position: fixed; inset: 0;
  background: rgba(10,14,26,0.85);
  display: flex; align-items: center; justify-content: center;
  z-index: 9100;
}
#ls-pin-overlay.hidden { display: none; }
#ls-pin-overlay .ls-pin-box {
  background: #1a1e2e;
  border: 1.5px solid #2a2e44;
  border-radius: 12px;
  padding: 26px 28px;
  max-width: 380px; width: 100%;
  color: #e4dfd0;
  font-family: 'EB Garamond', Georgia, serif;
}
#ls-pin-overlay h3 { color: #e8b830; font-family: 'Cinzel', serif; margin: 0 0 10px; font-size: 1.25rem; font-weight: 500; }
#ls-pin-overlay p { color: #a9a499; margin: 0 0 14px; line-height: 1.5; font-size: 0.94rem; }
#ls-pin-overlay input {
  width: 100%;
  background: rgba(10,14,26,0.7);
  border: 1.5px solid #3a3e54;
  border-radius: 7px;
  color: #e4dfd0;
  padding: 12px 14px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 1.4rem;
  letter-spacing: 0.4em;
  text-align: center;
  outline: none;
  box-sizing: border-box;
}
#ls-pin-overlay input:focus { border-color: #e8b830; }
#ls-pin-overlay .ls-pin-buttons { display: flex; gap: 10px; margin-top: 16px; }
#ls-pin-overlay button { flex: 1; }

/* ─── Session-created confirmation screen ─────────────────── */
#ls-screen-session-created {
  position: fixed; inset: 0;
  background: linear-gradient(180deg, #0a0e1a 0%, #0f1220 100%);
  color: #e4dfd0;
  font-family: 'EB Garamond', Georgia, serif;
  display: flex; align-items: center; justify-content: center;
  padding: 20px; z-index: 9000;
}
#ls-screen-session-created.hidden { display: none; }
#ls-screen-session-created .ls-sess-box {
  background: rgba(20,24,42,0.82);
  border: 1.5px solid #e8b830;
  border-radius: 14px;
  padding: 36px 32px;
  max-width: 520px; width: 100%;
  text-align: center;
}
#ls-screen-session-created h2 {
  font-family: 'Cinzel', serif; color: #e8b830; font-size: 1.3rem;
  margin: 0 0 8px; font-weight: 500;
}
#ls-screen-session-created .ls-sess-code {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 3.4rem;
  letter-spacing: 0.25em;
  color: #e8b830;
  margin: 14px 0;
  font-weight: 700;
  user-select: all;
}
#ls-screen-session-created .ls-sess-url {
  color: #a9a499;
  font-size: 0.92rem;
  margin: 6px 0 20px;
  font-family: 'IBM Plex Mono', monospace;
  word-break: break-all;
}
#ls-screen-session-created .ls-sess-actions {
  display: flex; gap: 10px; justify-content: center; flex-wrap: wrap;
}
#ls-screen-session-created button {
  background: #e8b830; color: #1a1e2e; border: none;
  padding: 11px 22px; border-radius: 7px; cursor: pointer;
  font-family: inherit; font-size: 0.98rem; font-weight: 600;
}
#ls-screen-session-created button.ls-btn-ghost {
  background: transparent; color: #e8b830; border: 1.5px solid #c9941a;
}

/* ─── Teacher banner (shows at top while logged in as teacher) ─ */
#ls-teacher-banner {
  position: fixed; top: 0; left: 0; right: 0;
  background: rgba(232,184,48,0.12);
  border-bottom: 1px solid #c9941a;
  color: #e8b830;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.84rem;
  padding: 7px 14px;
  display: flex; justify-content: space-between; align-items: center;
  z-index: 8000;
}
#ls-teacher-banner.hidden { display: none; }
#ls-teacher-banner button {
  background: transparent; color: #e8b830;
  border: 1px solid #c9941a; border-radius: 4px;
  padding: 4px 10px; font-family: inherit; font-size: 0.82rem;
  cursor: pointer; margin-left: 8px;
}
#ls-teacher-banner button:hover { background: rgba(232,184,48,0.15); }

/* Student-side "watching" indicator */
#ls-watching-indicator {
  position: fixed; top: 10px; right: 10px;
  background: rgba(239,68,68,0.9);
  color: white;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  padding: 4px 10px;
  border-radius: 4px;
  z-index: 8500;
  opacity: 0; transition: opacity 0.3s;
  pointer-events: none;
}
#ls-watching-indicator.show { opacity: 1; }
#ls-watching-indicator::before {
  content: '● ';
  animation: ls-pulse 1.2s infinite;
}
@keyframes ls-pulse {
  0%, 100% { opacity: 0.4; } 50% { opacity: 1; }
}

/* ─── Live Wall (teacher's class grid) ────────────────────── */
#ls-screen-live-wall {
  position: fixed; inset: 0;
  background: #0a0e1a;
  color: #e4dfd0;
  font-family: 'EB Garamond', Georgia, serif;
  display: flex; flex-direction: column;
  z-index: 8900;
}
#ls-screen-live-wall.hidden { display: none; }
#ls-screen-live-wall .ls-lw-head {
  display: flex; justify-content: space-between; align-items: center;
  padding: 14px 20px;
  border-bottom: 1px solid #2a2e44;
  background: rgba(20,24,42,0.6);
}
#ls-screen-live-wall .ls-lw-head h2 {
  font-family: 'Cinzel', serif; color: #e8b830;
  margin: 0; font-size: 1.25rem; font-weight: 500;
}
#ls-screen-live-wall .ls-lw-head .ls-lw-meta {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.84rem; color: #a9a499;
}
#ls-screen-live-wall .ls-lw-head button {
  background: transparent; color: #e8b830;
  border: 1.5px solid #c9941a; border-radius: 6px;
  padding: 7px 16px; font-family: inherit; font-size: 0.9rem;
  cursor: pointer;
}
#ls-wall-grid {
  flex: 1; overflow-y: auto;
  padding: 16px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 14px;
  align-content: start;
}
.ls-empty {
  grid-column: 1 / -1;
  text-align: center;
  color: #a9a499;
  padding: 60px 20px;
  font-size: 1.05rem;
}
.ls-empty strong {
  color: #e8b830;
  font-family: 'IBM Plex Mono', monospace;
  letter-spacing: 0.15em;
  font-size: 1.2rem;
}

.ls-card {
  background: #141828;
  border: 1px solid #2a2e44;
  border-radius: 8px;
  overflow: hidden;
  cursor: pointer;
  transition: transform 0.15s, border-color 0.15s;
}
.ls-card:hover {
  border-color: #e8b830;
  transform: translateY(-2px);
}
.ls-preview {
  aspect-ratio: 4 / 3;
  background: #0a0e1a;
  overflow: hidden;
  position: relative;
}
.ls-preview img {
  width: 100%; height: 100%; object-fit: cover;
  display: block;
}
.ls-preview-empty {
  display: flex; align-items: center; justify-content: center;
  width: 100%; height: 100%;
  color: #5a5a5a;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8rem;
}
.ls-card-head {
  display: flex; justify-content: space-between; align-items: center;
  padding: 8px 10px 4px;
}
.ls-card-name {
  color: #e4dfd0;
  font-family: 'EB Garamond', Georgia, serif;
  font-size: 0.98rem;
  font-weight: 600;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.ls-card-status {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  padding: 2px 6px;
  border-radius: 3px;
  white-space: nowrap;
}
.ls-card-status.ls-active { background: rgba(74,222,128,0.15); color: #4ade80; }
.ls-card-status.ls-stale  { background: rgba(232,184,48,0.12); color: #e8b830; }
.ls-card-status.ls-idle   { background: rgba(120,120,120,0.15); color: #888; }

.ls-card-row {
  display: flex; justify-content: space-between;
  padding: 0 10px 10px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.78rem;
  color: #a9a499;
}
.ls-screen { color: #c9941a; }
.ls-progress.ls-good { color: #4ade80; }
.ls-progress.ls-mid  { color: #e8b830; }
.ls-progress.ls-low  { color: #f87171; }

/* ─── Live wall detail overlay ──────────────────────────── */
.ls-detail-overlay {
  position: fixed; inset: 0;
  background: rgba(10,14,26,0.92);
  display: flex; align-items: center; justify-content: center;
  padding: 20px;
  z-index: 9500;
}
.ls-detail-inner {
  background: #141828;
  border: 1.5px solid #e8b830;
  border-radius: 12px;
  max-width: 1100px; width: 100%;
  max-height: 90vh;
  overflow: hidden;
  display: flex; flex-direction: column;
}
.ls-detail-head {
  display: flex; justify-content: space-between; align-items: flex-start;
  padding: 16px 22px;
  border-bottom: 1px solid #2a2e44;
}
.ls-detail-name {
  font-family: 'Cinzel', serif; color: #e8b830;
  font-size: 1.25rem; margin: 0; font-weight: 500;
}
.ls-detail-sub {
  font-family: 'IBM Plex Mono', monospace;
  color: #a9a499; font-size: 0.82rem;
  margin-top: 4px;
}
.ls-detail-close {
  background: transparent; color: #e8b830;
  border: 1.5px solid #c9941a; border-radius: 5px;
  padding: 7px 14px; font-family: inherit; font-size: 0.88rem;
  cursor: pointer;
}
.ls-detail-preview {
  flex: 1; min-height: 400px;
  background: #0a0e1a;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}
.ls-detail-preview img {
  max-width: 100%; max-height: 70vh; object-fit: contain;
  display: block;
}
.ls-detail-meta {
  padding: 14px 22px;
  border-top: 1px solid #2a2e44;
  display: flex; gap: 10px; flex-wrap: wrap;
  font-family: 'EB Garamond', Georgia, serif;
}

/* ────────────────────────────────────────────────────────────────
   Teacher push banner (student-side) — gold notification shown
   briefly when the teacher jumps the whole class to a new screen.
   ──────────────────────────────────────────────────────────────── */
#ls-push-banner {
  position: fixed; top: 14px; left: 50%; transform: translateX(-50%);
  background: linear-gradient(135deg, #e8b830 0%, #d4a020 100%);
  color: #1a1e2e; padding: 12px 22px; border-radius: 10px;
  font-family: 'EB Garamond', Georgia, serif; font-weight: 600; font-size: 1.02rem;
  box-shadow: 0 8px 32px rgba(0,0,0,0.4), 0 0 0 2px rgba(232,184,48,0.3);
  z-index: 10000; opacity: 0; pointer-events: none;
  transition: opacity 0.3s ease-out, transform 0.3s ease-out;
  max-width: 90vw; text-align: center;
}
#ls-push-banner.show { opacity: 1; transform: translateX(-50%) translateY(0); pointer-events: auto; }
#ls-push-banner.hide { opacity: 0; transform: translateX(-50%) translateY(-10px); }
#ls-push-banner .ls-pb-kicker {
  display: block; font-size: .72rem; letter-spacing: .12em; text-transform: uppercase;
  color: #1a1e2e; opacity: .7; font-weight: 700; margin-bottom: 2px;
}

/* ────────────────────────────────────────────────────────────────
   Teacher preview mode — login CTA + persistent banner
   ──────────────────────────────────────────────────────────────── */

/* "Preview content" button on login card: a small ghost link below the
   student/teacher panels.  Looks like a footer action, not a primary CTA. */
.ls-preview-cta {
  margin-top: 20px;
  padding-top: 14px;
  border-top: 1px solid rgba(232,184,48,0.15);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  flex-wrap: wrap;
}
.ls-btn-link {
  background: transparent;
  border: 1px dashed rgba(232,184,48,0.35);
  color: #c9941a;
  font-family: 'EB Garamond', Georgia, serif;
  font-size: 0.92rem;
  padding: 6px 14px;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.15s;
}
.ls-btn-link:hover {
  border-color: rgba(232,184,48,0.6);
  background: rgba(232,184,48,0.08);
  color: #e8b830;
}
.ls-preview-hint {
  font-size: 0.74rem;
  color: #7a8099;
  font-family: ui-monospace, monospace;
  letter-spacing: 0.04em;
}

/* Persistent top banner shown while in teacher preview mode.  Gold strip
   with the jump-to dropdown + exit button. */
#ls-preview-banner {
  position: fixed;
  top: 0; left: 0; right: 0;
  background: linear-gradient(135deg, #e8b830 0%, #d4a020 100%);
  color: #1a1e2e;
  padding: 8px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
  z-index: 9999;
  box-shadow: 0 2px 12px rgba(0,0,0,0.3);
  font-family: 'EB Garamond', Georgia, serif;
}
#ls-preview-banner.hidden { display: none; }
#ls-preview-banner .ls-preview-banner-text {
  font-weight: 500;
  font-size: 0.95rem;
}
#ls-preview-banner .ls-preview-banner-controls {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}
#ls-preview-banner .ls-preview-jump-label {
  font-family: ui-monospace, monospace;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  font-weight: 700;
  opacity: 0.75;
}
#ls-preview-banner select {
  background: rgba(26,30,46,0.15);
  color: #1a1e2e;
  border: 1px solid rgba(26,30,46,0.3);
  border-radius: 6px;
  padding: 4px 10px;
  font: inherit;
  font-size: 0.88rem;
  cursor: pointer;
  min-width: 180px;
}
#ls-preview-banner select:hover { background: rgba(26,30,46,0.22); }
#ls-preview-banner button {
  background: rgba(26,30,46,0.85);
  color: #e8b830;
  border: 1px solid rgba(26,30,46,0.9);
  border-radius: 6px;
  padding: 5px 12px;
  font-family: inherit;
  font-size: 0.88rem;
  cursor: pointer;
  transition: background 0.15s;
}
#ls-preview-banner button:hover { background: #1a1e2e; }

/* Push the app content down so it doesn't hide behind the preview banner.
   The banner is ~44px tall on desktop; mobile wraps to ~68px. */
body.ls-preview-active { padding-top: 50px; }
@media (max-width: 700px) {
  body.ls-preview-active { padding-top: 80px; }
}