:root {
  --bg: #f6f5fb;
  --surface: #ffffff;
  --ink: #1b1730;
  --muted: #5c5674;
  --line: #e4e0f0;
  --indigo: #312e81;
  --indigo-2: #3c388f;
  --purple: #6d28d9;
  --soft: #efeaff;
  --good: #166534;
  --bad: #9f1239;
  --shadow: 0 18px 40px rgba(32, 24, 72, 0.08);
  --radius: 18px;
  --font: "Figtree", "Avenir Next", "Segoe UI", sans-serif;
  --display: "Fraunces", "Iowan Old Style", Palatino, serif;
  --chalk-font: "Caveat", "Segoe Print", cursive;
  --board: #143528;
  --board-2: #1c4a38;
  --chalk: #f4f0e2;
  --wood-a: #6b3f28;
  --wood-b: #4a2a1b;
  color: var(--ink);
  background: var(--bg);
  font-family: var(--font);
  font-size: 16.5px;
  line-height: 1.5;
}

* { box-sizing: border-box; }
html, body { margin: 0; min-height: 100%; }
body { background: var(--bg); }
img, svg { display: block; max-width: 100%; }
button, input, textarea { font: inherit; color: inherit; }
button, [role="button"] { cursor: pointer; }
button:disabled { cursor: not-allowed; opacity: 0.6; }
:focus-visible { outline: 2px solid var(--purple); outline-offset: 2px; }
[hidden] { display: none !important; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

h1, h2, h3 {
  font-family: var(--display);
  font-weight: 560;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin: 0;
}
h1 { font-size: clamp(2.2rem, 4vw, 3.6rem); }
h2 { font-size: clamp(1.5rem, 2vw, 2rem); }
h3 { font-size: 1.25rem; }
p { margin: 0; }

.screen { min-height: 100vh; }
.wrap { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.muted { color: var(--muted); }
.eyebrow {
  margin: 0 0 6px;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--purple);
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px;
}

.btn {
  min-height: 44px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid transparent;
  background: var(--surface);
  font-weight: 650;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}
.btn.primary { background: var(--indigo); color: #fff; }
.btn.primary:hover { background: var(--indigo-2); }
.btn.secondary { background: var(--soft); color: var(--indigo); }
.btn.live { background: var(--purple); color: #fff; }
.btn.live:hover { filter: brightness(1.05); }
.btn.ghost { background: transparent; border-color: var(--line); color: var(--ink); }
.btn.icon { width: 44px; padding: 0; border-color: var(--line); font-family: var(--display); font-size: 1.15rem; }

.auth-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(280px, 420px);
  gap: 40px;
  align-items: center;
  width: min(1080px, calc(100% - 40px));
  margin: 0 auto;
  padding: 48px 0 64px;
}
.story-list { list-style: none; padding: 0; margin: 28px 0 0; display: grid; gap: 14px; }
.story-list li { display: grid; gap: 2px; padding-left: 14px; border-left: 3px solid var(--indigo); }
.story-list span { color: var(--muted); }
.lede { margin-top: 16px; font-size: 1.08rem; color: var(--muted); max-width: 40rem; }
.auth-card { display: grid; gap: 14px; }
.tabs { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; background: var(--bg); padding: 4px; border-radius: 999px; }
.tabs button { min-height: 40px; border: 0; background: transparent; border-radius: 999px; font-weight: 700; }
.tabs button[aria-selected="true"] { background: var(--surface); color: var(--indigo); box-shadow: 0 1px 2px rgba(27, 23, 48, 0.08); }

form { display: grid; gap: 12px; }
label { display: grid; gap: 6px; font-weight: 600; font-size: 0.92rem; }
input, textarea, select {
  width: 100%;
  min-height: 44px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #fff;
}
textarea { min-height: 76px; resize: vertical; line-height: 1.45; }

.brand-lockup { display: inline-flex; align-items: center; gap: 10px; font-family: var(--display); font-weight: 680; font-size: 1.25rem; margin: 0 0 18px; }
.brand-btn { border: 0; background: transparent; padding: 0; margin: 0; min-height: 44px; }
.mark { width: 32px; height: 32px; flex: none; }
.mark svg { width: 32px; height: 32px; }
.mark rect { fill: var(--board); }
.mark path, .mark circle { fill: none; stroke: var(--chalk); stroke-width: 1.7; stroke-linecap: round; }
.mark circle { stroke: #ddd6fe; }

.profile-card { width: min(720px, calc(100% - 32px)); margin: 32px auto; display: grid; gap: 14px; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.span-2 { grid-column: span 2; }
.subjects { border: 1px solid var(--line); border-radius: 14px; margin: 0; padding: 12px; }
.subjects legend { font-weight: 700; padding: 0 6px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; min-height: 8px; }
.chip { display: inline-flex; align-items: center; gap: 6px; background: var(--soft); color: var(--indigo); border-radius: 999px; padding: 6px 8px 6px 12px; font-weight: 650; }
.chip button { border: 0; background: transparent; min-height: 32px; width: 32px; border-radius: 999px; color: var(--indigo); }
.chip-add { display: flex; gap: 8px; margin-top: 10px; }
.chip-add input { flex: 1; }
.row-actions { display: flex; flex-wrap: wrap; gap: 8px; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  background: rgba(246, 245, 251, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; gap: 4px; }
.nav button, .lang button {
  min-height: 40px;
  padding: 0 12px;
  border: 0;
  background: transparent;
  border-radius: 999px;
  font-weight: 700;
  color: var(--muted);
}
.nav button[aria-current="page"], .lang button[aria-pressed="true"] { background: var(--soft); color: var(--indigo); }
.top-actions { display: flex; align-items: center; gap: 8px; margin-left: auto; }
.lang { display: flex; background: #fff; border: 1px solid var(--line); border-radius: 999px; padding: 2px; }

.banner {
  background: #fff7ed;
  color: #7c2d12;
  border: 1px solid #fed7aa;
  border-radius: 12px;
  padding: 10px 12px;
  font-size: 0.95rem;
}
.banner.wrap { width: min(1120px, calc(100% - 32px)); margin: 12px auto 0; }
.guest-note { margin: 12px auto 0; color: var(--muted); }

main.wrap { padding: 22px 0 64px; }
.section-head { display: flex; justify-content: space-between; gap: 12px; align-items: end; margin-bottom: 14px; }
.desk { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 18px; align-items: start; }
.thread {
  min-height: 280px;
  max-height: min(58vh, 640px);
  overflow: auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-right: 4px;
}
.bubble { max-width: min(100%, 46rem); padding: 12px 14px; border-radius: 16px; }
.bubble.user { margin-left: auto; background: var(--indigo); color: #fff; border-bottom-right-radius: 6px; white-space: pre-wrap; }
.bubble.assistant { background: var(--bg); border: 1px solid var(--line); border-bottom-left-radius: 6px; }
.composer { display: grid; grid-template-columns: 1fr auto; gap: 8px; align-items: end; margin-top: 12px; }
.materials { position: sticky; top: 84px; }
.material-list, .plain-list { list-style: none; padding: 0; margin: 12px 0 0; display: grid; gap: 10px; }
.material { border-top: 1px solid var(--line); padding-top: 10px; }
.material h3 { font-family: var(--font); font-size: 1rem; }
.material p, .subtopics { color: var(--muted); font-size: 0.92rem; margin-top: 4px; }
.file-btn input { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0, 0, 0, 0); }
.file-btn span {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  border-radius: 12px;
  border: 1px dashed var(--indigo);
  color: var(--indigo);
  font-weight: 700;
}
.upload { margin-bottom: 8px; }

.week { display: grid; grid-template-columns: repeat(7, minmax(0, 1fr)); gap: 10px; }
.day { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 10px; min-height: 140px; }
.day h3 { font-family: var(--font); font-size: 0.95rem; margin-bottom: 8px; }
.block { background: var(--soft); border-radius: 10px; padding: 8px; margin-top: 8px; }
.block strong { display: block; font-size: 0.82rem; color: var(--indigo); }
.block span { display: block; font-size: 0.85rem; }

.vision-grid { display: grid; grid-template-columns: 240px minmax(0, 1fr) minmax(0, 1fr); gap: 16px; align-items: start; }
.countdown { font-family: var(--display); font-size: clamp(2.4rem, 4vw, 3.4rem); line-height: 1; margin: 8px 0; }
.countdown-card { display: grid; gap: 8px; align-content: start; }
.next-class { margin-top: 16px; padding-top: 12px; border-top: 1px solid var(--line); display: grid; gap: 10px; }

.inline-form { display: grid; grid-template-columns: 1fr 1.4fr auto; gap: 12px; align-items: end; margin-bottom: 16px; }
.stack { display: grid; gap: 12px; }
.question { background: var(--surface); border: 1px solid var(--line); border-radius: 16px; padding: 14px; display: grid; gap: 8px; }
.choice { display: flex; gap: 10px; align-items: flex-start; font-weight: 550; background: var(--bg); border-radius: 12px; padding: 10px 12px; }
.choice input { width: 18px; min-height: 18px; margin-top: 3px; }
.grade-line { padding-top: 8px; border-top: 1px solid var(--line); }

.board-frame {
  background:
    linear-gradient(90deg, rgba(255, 255, 255, 0.18), transparent 10% 90%, rgba(0, 0, 0, 0.25)),
    repeating-linear-gradient(90deg, var(--wood-a) 0 12px, var(--wood-b) 12px 22px, #7d4b31 22px 34px);
  padding: 16px;
  border-radius: 18px;
  box-shadow: 0 22px 40px rgba(48, 24, 12, 0.22), inset 0 0 0 2px #3a2014;
}
.board {
  position: relative;
  min-height: 420px;
  border-radius: 8px;
  background:
    radial-gradient(900px 240px at 50% 0%, rgba(255, 255, 255, 0.06), transparent 55%),
    linear-gradient(180deg, var(--board-2), var(--board) 42%, #0e291e);
  color: var(--chalk);
  box-shadow: inset 0 0 70px rgba(0, 0, 0, 0.35);
  overflow: hidden;
}
.board::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: radial-gradient(rgba(255, 255, 255, 0.16) 0.6px, transparent 0.7px);
  background-size: 3px 3px;
  opacity: 0.25;
}
.board-stage {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 16px;
  padding: 28px 26px 36px;
  min-height: 420px;
  align-content: start;
}
.board-stage[data-layout="two"] { grid-template-columns: 1fr 1fr; }
.board-stage[data-layout="three"] { grid-template-columns: 1fr 1fr 1fr; }
.chalk-title, .chalk-text { font-family: var(--chalk-font); color: var(--chalk); text-shadow: 0 0 1px rgba(244, 240, 226, 0.4); }
.chalk-title { font-size: clamp(2rem, 4vw, 3.1rem); line-height: 1.05; margin: 0; }
.chalk-text { font-size: 1.55rem; line-height: 1.25; }
.chalk-text p { margin: 0 0 8px; }
.chalk-draw { width: 100%; height: 220px; }
.chalk-draw text { font-family: var(--chalk-font); }
.ledge { height: 14px; margin: 8px 18px 0; border-radius: 0 0 8px 8px; background: linear-gradient(#8a5a3b, #3d2418); }
.class-meta, .class-tools { display: flex; justify-content: space-between; gap: 12px; align-items: end; margin: 8px 0 12px; }
.class-tools { align-items: center; flex-wrap: wrap; }
.progress-label { color: var(--muted); font-weight: 700; }
.class-setup { margin-bottom: 16px; display: grid; gap: 8px; }
.hand-panel { margin-top: 14px; display: grid; gap: 10px; }
.chalk-answer { background: #10281e; color: var(--chalk); border-radius: 12px; padding: 12px 14px; }
.chalk-answer a { color: #ddd6fe; }

.prose h1, .prose h2, .prose h3 { font-family: var(--font); font-size: 1.05rem; margin: 0 0 6px; }
.prose p, .prose ul, .prose ol { margin: 0 0 8px; }
.prose ul, .prose ol { padding-left: 1.2rem; }
.prose code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.9em; background: var(--soft); padding: 0 4px; border-radius: 4px; }
.bubble.assistant .prose code { background: #fff; }
.prose pre { overflow: auto; padding: 10px; background: #1b1730; color: #f6f5fb; border-radius: 10px; }
.prose pre code { background: transparent; color: inherit; padding: 0; }

#info-modal { border: 0; padding: 0; background: transparent; width: min(640px, calc(100% - 24px)); }
#info-modal::backdrop { background: rgba(27, 23, 48, 0.46); }
.info-card { background: var(--surface); border-radius: var(--radius); padding: 20px; border: 1px solid var(--line); }

#toast-root { position: fixed; right: 16px; bottom: 16px; display: grid; gap: 8px; z-index: 20; width: min(360px, calc(100% - 32px)); }
.toast { background: var(--ink); color: #fff; border-radius: 12px; padding: 12px 14px; box-shadow: var(--shadow); }

.empty { color: var(--muted); margin: 8px 0 0; }

@media (max-width: 980px) {
  .auth-layout, .desk, .vision-grid, .week, .inline-form, .form-grid { grid-template-columns: 1fr; }
  .span-2 { grid-column: auto; }
  .materials { position: static; }
  .topbar { flex-wrap: wrap; }
  .nav { order: 3; width: 100%; overflow-x: auto; }
  .board-stage[data-layout="two"], .board-stage[data-layout="three"] { grid-template-columns: 1fr; }
  .auth-layout { padding: 18px 0 40px; gap: 18px; width: min(1080px, calc(100% - 28px)); }
  .story .lede, .story-list { display: none; }
  .brand-lockup { margin-bottom: 8px; }
}

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

/* ---------- teacher-led home, quota, queue ---------- */
.small { font-size: 0.86rem; }
.sub-h { font-family: var(--font); font-size: 1rem; margin-top: 16px; }
.quota-pill { font-size: 0.85rem; font-weight: 700; color: var(--indigo); background: var(--soft); border-radius: 999px; padding: 6px 12px; white-space: nowrap; }
.quota-pill[data-low="true"] { background: #fff1f2; color: var(--bad); }
.today-grid { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); gap: 16px; align-items: start; }
.today-main { display: grid; gap: 12px; grid-row: span 3; align-content: start; }
.today-main h2 { font-size: clamp(1.7rem, 3vw, 2.4rem); }
.today-reason { color: var(--muted); font-size: 1.05rem; max-width: 42rem; }
.today-blocks { display: grid; gap: 4px; margin-top: 8px; }
.meter { height: 10px; border-radius: 999px; background: var(--soft); overflow: hidden; margin: 8px 0; }
.meter span { display: block; height: 100%; width: 0; background: linear-gradient(90deg, var(--indigo), var(--purple)); border-radius: 999px; transition: width 0.4s ease; }
.block em { display: inline-block; font-style: normal; font-size: 0.72rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: var(--purple); margin-bottom: 2px; }
.block.act-class { background: #ede9fe; }
.block.act-exercise { background: #fef3c7; }
.block.act-exercise em { color: #92400e; }
.block.act-revision { background: #dcfce7; }
.block.act-revision em { color: var(--good); }
.block.act-reading { background: var(--soft); }
.day.is-today { border-color: var(--purple); box-shadow: 0 0 0 2px rgba(109, 40, 217, 0.15); }
.ask-exercise { display: grid; gap: 12px; margin-bottom: 12px; }
.queue-box { border: 1px dashed var(--purple); border-radius: 14px; background: var(--soft); padding: 16px; display: grid; gap: 12px; }
.queue-text { font-weight: 600; color: var(--indigo); }
.queue-dots { display: flex; gap: 6px; }
.queue-dots i { width: 10px; height: 10px; border-radius: 50%; background: var(--purple); opacity: 0.25; animation: pulse-dot 1.2s infinite ease-in-out; }
.queue-dots i:nth-child(2) { animation-delay: 0.2s; }
.queue-dots i:nth-child(3) { animation-delay: 0.4s; }
@keyframes pulse-dot { 0%, 100% { opacity: 0.25; } 50% { opacity: 1; } }
.brand-btn span:last-child, .nav button, .top-actions .btn, .quota-pill { white-space: nowrap; }
.topbar { flex-wrap: wrap; row-gap: 4px; }
.nav button { padding: 0 10px; }
@media (max-width: 980px) {
  .today-grid { grid-template-columns: 1fr; }
  .today-main { grid-row: auto; }
  .quota-pill { order: 2; }
}