@import url('https://fonts.googleapis.com/css2?family=Source+Serif+4:wght@600;700&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@500;600&display=swap');

:root {
  /* base surfaces — warm ivory, like washi paper */
  --bg: #f5efe1;
  --surface: #fffdf8;
  --surface-sunken: #efe6d1;
  --border: #e1d4b3;
  --border-strong: #cbb98f;

  /* text — warm ink, not cool gray */
  --ink: #241d14;
  --ink-soft: #5c5240;
  --ink-faint: #8f8368;

  /* accents */
  --accent: #a6332b;          /* vermillion — primary action, lessons */
  --accent-dark: #872822;
  --accent-tint: #f3e0dc;
  --secondary: #8a6d2e;       /* ochre gold — reviews, secondary accent */
  --secondary-dark: #715a25;
  --secondary-tint: #f1e8d2;

  /* belts — kept for reference; actual per-badge colors come from js/srs.js */
  --belt-white: #ffffff;
  --belt-yellow: #e3ac0f;
  --belt-orange: #d9781f;
  --belt-red: #a6332b;
  --belt-green: #1f8a5f;
  --belt-purple: #7c3aed;
  --belt-blue: #3355c9;
  --belt-brown: #8a5a34;
  --belt-black: #22262b;

  --ok: #2e7d4f;
  --bad: #b8541d;

  --font-serif: 'Source Serif 4', Georgia, 'Times New Roman', serif;   /* headlines, brand */
  --font-body: 'Inter', 'Segoe UI', sans-serif;                       /* everything else */
  --font-mono: 'JetBrains Mono', monospace;

  --radius: 10px;
  --sidebar-w: 240px;
  --shadow-sm: 0 1px 2px rgba(36,29,20,0.06);
  --shadow-md: 0 8px 22px rgba(36,29,20,0.08);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

h1, h2, h3 {
  font-family: var(--font-serif);
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 0.3em;
  color: var(--ink);
}

.muted { color: var(--ink-faint); font-size: 0.9em; }

/* ---------- buttons ---------- */
.btn {
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 0.7em 1.5em;
  border-radius: 8px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.12s ease, opacity 0.12s ease, background 0.12s ease, border-color 0.12s ease;
}
.btn:active { transform: scale(0.98); }
.btn:disabled { opacity: 0.4; cursor: not-allowed; }
.btn-primary { background: var(--accent); color: #ffffff; box-shadow: var(--shadow-sm); }
.btn-primary:hover:not(:disabled) { background: var(--accent-dark); }
.btn-ghost { background: transparent; color: var(--ink-soft); border-color: var(--border-strong); }
.btn-ghost:hover { color: var(--ink); border-color: var(--ink-faint); background: var(--surface-sunken); }
.btn-lg { font-size: 1rem; padding: 0.85em 1.9em; display: inline-flex; align-items: center; justify-content: center; gap: 9px; }
.btn-lg .icon { width: 17px; height: 17px; margin: 0; }

/* ---------- seal mark (logo) ---------- */
.belt-knot {
  width: 38px; height: 38px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: var(--shadow-sm), inset 0 0 0 3px rgba(253, 246, 236, 0.35);
  flex-shrink: 0;
}
.belt-knot.small { width: 26px; height: 26px; box-shadow: var(--shadow-sm), inset 0 0 0 2px rgba(253, 246, 236, 0.35); }

/* ---------- icons ---------- */
.icon { width: 18px; height: 18px; stroke: currentColor; fill: none; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; vertical-align: -4px; flex-shrink: 0; }
.icon.lg { width: 26px; height: 26px; }

/* ---------- shared decorative illustration ---------- */
/* Fixed, non-interactive, sits behind everything. Hidden below 900px so it
   never crowds smaller viewports. Assets live in assets/decor/. The sun is
   a plain image keeping its own red. The mountain uses background-image
   (NOT a CSS mask) and deliberately keeps its original ink-wash grays
   rather than theme-tinting — that was a deliberate fix, don't convert it
   back to a mask. Note its sizing pattern too: explicit width +
   height:auto + aspect-ratio. Using left+right to imply the width instead
   silently computes a wrong height. */
.page-decor {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}
.page-decor img,
.page-decor > div {
  position: absolute;
}
.decor-mountain {
  position: absolute;
  bottom: 0;
  left: var(--sidebar-w);
  width: calc(100vw - var(--sidebar-w));
  height: auto;
  aspect-ratio: 1376 / 768;
  background-image: url('../assets/decor/mountains.png?v=3');
  background-size: 100% 100%;
  background-position: bottom left;
  background-repeat: no-repeat;
  opacity: 0.18;
  /* Keep the original colors */
}
.decor-sun {
  top: -70px; right: -70px;
  width: 320px; height: 316px;
  opacity: 0.3;
}
@media (max-width: 900px) {
  .page-decor { display: none; }
}

/* ---------- auth screen ---------- */
.auth-screen {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 24px;
  position: relative;
  background:
    radial-gradient(circle at 12% 8%, rgba(166,51,43,0.07), transparent 42%),
    radial-gradient(circle at 88% 92%, rgba(138,109,46,0.08), transparent 42%),
    var(--bg);
  /* no sidebar exists on this screen, so the decor shouldn't leave room for one */
  --sidebar-w: 0px;
}
.auth-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  padding: 40px;
  width: 100%; max-width: 380px;
  position: relative;
  z-index: 1;
}
.auth-brand { text-align: center; margin-bottom: 28px; }
.auth-brand .belt-knot { margin: 0 auto 14px; width: 50px; height: 50px; box-shadow: var(--shadow-sm), inset 0 0 0 4px rgba(253, 246, 236, 0.35); }
.auth-brand h1 { font-size: 2rem; margin-bottom: 0.15em; }
.auth-brand-sub { display: block; font-size: 0.42em; font-weight: 500; color: var(--ink-faint); letter-spacing: 0.1em; text-transform: uppercase; margin-top: 4px; }
.auth-tagline { color: var(--ink-faint); margin: 0; font-size: 0.92rem; }
.auth-form { display: flex; flex-direction: column; gap: 14px; }
.auth-form label { display: flex; flex-direction: column; gap: 6px; font-size: 0.83rem; color: var(--ink-soft); font-weight: 500; }
.name-fields { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 14px; }
.auth-form input {
  font-family: var(--font-body);
  background: var(--surface);
  border: 1px solid var(--border-strong);
  color: var(--ink);
  padding: 0.65em 0.85em;
  border-radius: 7px;
  font-size: 1rem;
}
.auth-form input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-tint); }
.auth-error { min-height: 1.2em; font-size: 0.85rem; margin: 0; }

.config-warning { max-width: 560px; margin: 80px auto; padding: 24px; background: var(--surface); border: 1px solid var(--bad); border-radius: var(--radius); box-shadow: var(--shadow-md); }
.config-warning code { background: var(--surface-sunken); padding: 2px 6px; border-radius: 4px; }

/* ---------- shell / sidebar ---------- */
.shell { min-height: 100vh; display: flex; }
.sidebar {
  width: var(--sidebar-w); flex-shrink: 0;
  display: flex; flex-direction: column;
  padding: 26px 18px;
  border-right: 1px solid var(--border);
  background: var(--surface);
  position: sticky; top: 0; height: 100vh;
  overflow-y: auto;
  z-index: 2;
}
.brand { display: flex; align-items: center; gap: 10px; margin-bottom: 32px; padding: 0 6px; }
.brand-title { font-family: var(--font-serif); font-size: 1.02rem; font-weight: 700; line-height: 1.2; }
.brand-sub { font-family: var(--font-mono); font-size: 0.66rem; color: var(--ink-faint); letter-spacing: 0.08em; text-transform: uppercase; margin-top: 1px; }

.sidebar nav { display: flex; flex-direction: column; gap: 3px; flex: 1; min-width: 0; }
.nav-label-short { display: none; }
.sidebar nav a {
  display: flex; align-items: center; gap: 11px;
  text-decoration: none; color: var(--ink-soft); font-family: var(--font-body);
  font-weight: 600; font-size: 0.92rem; padding: 10px 12px; border-radius: 8px;
}
.sidebar nav a.active { color: var(--accent); background: var(--accent-tint); }
.sidebar nav a:hover:not(.active) { color: var(--ink); background: var(--surface-sunken); }

.sidebar-footer { display: flex; flex-direction: column; gap: 8px; padding-top: 14px; margin-top: 14px; border-top: 1px solid var(--border); }
.sidebar-footer .btn { width: 100%; justify-content: center; display: flex; align-items: center; gap: 8px; }

.content { flex: 1; min-width: 0; padding: 40px 32px 60px; max-width: 980px; width: 100%; margin: 0 auto; position: relative; z-index: 1; }

.loading { padding: 100px 0; text-align: center; color: var(--ink-faint); font-family: var(--font-body); font-weight: 500; font-size: 1.1rem; }

/* ---------- dashboard ---------- */
.hero-row { display: grid; grid-template-columns: 1.3fr 1fr; gap: 20px; margin-bottom: 44px; }
.hero-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 30px; box-shadow: var(--shadow-sm); display: flex; flex-direction: column; justify-content: center;
}
.hero-eyebrow {
  display: inline-flex; align-items: center; gap: 6px; width: fit-content;
  font-family: var(--font-mono); color: var(--accent); background: var(--accent-tint);
  font-size: 0.75rem; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase;
  padding: 4px 10px; border-radius: 20px; margin-bottom: 12px;
}
.hero-card h1 { font-size: 1.8rem; }
.hero-card p { color: var(--ink-soft); margin: 0; }

.action-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-bottom: 44px; }
.action-card {
  display: flex; align-items: center; gap: 16px;
  text-decoration: none; border-radius: var(--radius); padding: 20px;
  border: 1px solid var(--border); background: var(--surface); box-shadow: var(--shadow-sm);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}
.action-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.action-card.disabled { opacity: 0.5; pointer-events: none; }
.action-icon { width: 44px; height: 44px; border-radius: 10px; display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.action-card.lessons .action-icon { background: var(--accent-tint); color: var(--accent); }
.action-card.reviews .action-icon { background: var(--secondary-tint); color: var(--secondary); }
.action-count { font-family: var(--font-body); font-size: 1.9rem; font-weight: 700; line-height: 1; }
.action-label { color: var(--ink-faint); font-size: 0.85rem; margin-top: 2px; }

.forecast-section { margin: -20px 0 44px; }
.forecast-section h2 { font-size: 1.2rem; margin-bottom: 14px; }

/* the next unlock gets its own block — it's the one bit of the forecast a
   student actually plans around, so it shouldn't be a chip among chips */
.forecast-next {
  display: flex; align-items: center; gap: 16px; min-width: 0;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); padding: 16px 20px; margin-bottom: 12px;
}
.forecast-next-count {
  flex-shrink: 0; min-width: 54px; height: 54px; padding: 0 10px;
  display: flex; align-items: center; justify-content: center; border-radius: 12px;
  background: var(--secondary-tint); color: var(--secondary-dark);
  font-family: var(--font-mono); font-size: 1.5rem; font-weight: 600;
}
.forecast-next-body { min-width: 0; }
.forecast-next-label {
  font-size: 0.7rem; font-weight: 700; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--ink-faint);
}
.forecast-next-time {
  display: flex; align-items: baseline; flex-wrap: wrap; gap: 10px; margin-top: 3px;
  font-family: var(--font-body); font-size: 1.35rem; font-weight: 700; color: var(--ink);
}
.forecast-next-gap { font-family: var(--font-mono); font-size: 0.8rem; font-weight: 500; color: var(--ink-faint); }

.forecast-row { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; font-size: 0.85rem; }
.forecast-chip {
  font-family: var(--font-mono); font-size: 0.76rem; font-weight: 600;
  background: var(--surface-sunken); border: 1px solid var(--border); color: var(--ink-soft);
  padding: 4px 11px; border-radius: 20px;
}

.levelup-banner, .levelup-inline {
  background: #f6ecd3; color: #6b5410; border: 1px solid #e4d19c;
  padding: 12px 18px; border-radius: 8px; font-family: var(--font-body); font-weight: 600;
  margin-bottom: 20px; text-align: center;
}

.belt-rack h2 { font-size: 1.2rem; margin-bottom: 16px; }

.activity-section { margin-top: 40px; }
.activity-section h2 { font-size: 1.2rem; margin-bottom: 16px; display: flex; align-items: center; gap: 10px; }
.streak-pill {
  display: inline-flex; align-items: center; gap: 5px;
  font-family: var(--font-mono); font-size: 0.72rem; font-weight: 600;
  color: var(--secondary-dark); background: var(--secondary-tint);
  padding: 3px 10px; border-radius: 20px;
}
.streak-pill .icon { width: 13px; height: 13px; }
.heatmap-wrap {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); padding: 18px 20px;
}
.heatmap-row { display: flex; gap: 4px; }
.heatmap-cell {
  flex: 1; aspect-ratio: 1; min-width: 6px; border-radius: 3px;
  background: var(--surface-sunken); border: 1px solid var(--border);
}
.heatmap-cell.active { background: var(--accent); border-color: var(--accent); }
/* rest day — nothing was due, so it held the streak. Visibly distinct from
   both a studied day and a missed one. */
.heatmap-cell.rest {
  background: transparent;
  border-color: var(--secondary);
  border-style: dashed;
}
.heatmap-cell.today { box-shadow: 0 0 0 2px var(--secondary); }
.heatmap-caption { margin-top: 10px; font-size: 0.78rem; }
/* Grid rather than wrapping flex. A flex row of fixed 88px cards left-huddles
   and leaves a ragged gap on the right, which reads as broken next to the
   full-width cards above and below it. auto-fit + minmax lets the cards
   stretch to fill whatever width is available, so the rack lines up flush
   with every other section at any screen size. */
.belt-row {
  display: grid;
  /* 9 belts, so only 3 and 9 columns divide evenly — anything else orphans a
     card on a short final row, which is the ragged look being fixed here.
     3 by default, 9 once there's genuinely room for them. */
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}
@media (min-width: 1150px) {
  .belt-row { grid-template-columns: repeat(9, minmax(0, 1fr)); }
}
.belt-col {
  text-align: center; min-width: 0; background: var(--surface); border: 1px solid var(--border);
  border-radius: 9px; padding: 10px 6px; box-shadow: var(--shadow-sm);
}
/* a belt with nothing in it shouldn't compete for attention with one that has
   terms in it — the eye should land on where the student actually is */
.belt-col.is-empty { opacity: 0.55; box-shadow: none; }
.belt-col.is-empty .belt-count { color: var(--ink-faint); font-weight: 500; }

.belt-count { font-family: var(--font-mono); font-size: 1.05rem; font-weight: 600; color: var(--ink); }
.belt-swatch { height: 8px; border-radius: 4px; margin: 8px 0 6px; background: var(--belt-color); box-shadow: inset 0 0 0 1px rgba(0,0,0,0.08); }
.belt-label { font-size: 0.66rem; color: var(--ink-faint); line-height: 1.2; }

/* ---------- belt badges ---------- */
.belt-badge {
  display: inline-flex; align-items: center; gap: 5px;
  font-family: var(--font-mono); font-size: 0.72rem; font-weight: 600;
  padding: 3px 10px 3px 8px; border-radius: 12px; color: var(--ink-soft);
  background: var(--surface-sunken); border: 1px solid var(--border);
}
.belt-badge::before { content: ''; width: 8px; height: 8px; border-radius: 50%; background: var(--belt-color); box-shadow: inset 0 0 0 1px rgba(0,0,0,0.12); }
.belt-badge.small { padding: 2px 9px 2px 7px; font-size: 0.68rem; }

/* ---------- term list ---------- */
.level-section { margin-bottom: 30px; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 8px 20px 4px; box-shadow: var(--shadow-sm); overflow-x: auto; }
.level-section h3 { font-size: 1.1rem; margin: 14px 0 8px; display: flex; align-items: center; gap: 10px; }
.level-section h3 .muted { font-family: var(--font-body); font-weight: 400; font-size: 0.72em; }
.term-table { width: 100%; min-width: 480px; border-collapse: collapse; }
.term-table td { padding: 11px 6px; border-top: 1px solid var(--border); vertical-align: middle; }
.term-table tr.locked { opacity: 0.4; }
.term-cell { font-family: var(--font-body); font-weight: 700; font-size: 1.02rem; width: 34%; }
.term-search-input {
  display: block; width: 100%; max-width: 360px; margin: 18px 0 22px;
  font-family: var(--font-body); font-size: 0.95rem;
  background: var(--surface); border: 1px solid var(--border-strong); color: var(--ink);
  padding: 0.6em 0.85em; border-radius: 8px;
}
.term-search-input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-tint); }
.term-search-empty { margin-top: 20px; }

/* ============ LESSON / REVIEW SESSIONS ============ */
/* Both flows share one visual language. The only difference is the accent:
   lessons run on vermillion (--accent), reviews on ochre (--secondary),
   switched by the data-tone attribute so nothing has to be duplicated. */
.session-wrap { max-width: 620px; margin: 4px auto 0; }

/* ---------- session header: kicker, streak, count, progress track ---------- */
.session-bar {
  --tone: var(--accent);
  --tone-tint: var(--accent-tint);
  margin-bottom: 20px;
}
.session-bar[data-tone="secondary"] { --tone: var(--secondary); --tone-tint: var(--secondary-tint); }
.session-bar-top {
  display: flex; align-items: center; justify-content: space-between;
  gap: 10px; margin-bottom: 10px; min-width: 0;
}
.session-kicker {
  min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
  font-weight: 700; font-size: 0.72rem; letter-spacing: 0.15em;
  text-transform: uppercase; color: var(--tone);
}
.session-bar-right { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.session-count { font-family: var(--font-mono); font-size: 0.82rem; font-weight: 600; color: var(--ink-soft); }
.session-count-sep { color: var(--ink-faint); margin: 0 3px; }
.session-streak { padding: 2px 9px; font-size: 0.72rem; }
.session-exit {
  display: inline-flex; align-items: center; justify-content: center;
  width: 30px; height: 30px; padding: 0; border-radius: 8px; cursor: pointer;
  background: transparent; border: 1px solid var(--border-strong); color: var(--ink-faint);
  transition: color 0.12s ease, border-color 0.12s ease, background 0.12s ease;
}
.session-exit:hover { color: var(--bad); border-color: var(--bad); background: var(--surface); }
.session-exit .icon { width: 15px; height: 15px; margin: 0; }
.session-track {
  height: 6px; border-radius: 99px; overflow: hidden;
  background: var(--surface-sunken); border: 1px solid var(--border);
}
.session-track-fill {
  height: 100%; border-radius: 99px; background: var(--tone);
  transition: width 0.45s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---------- teaching card (one per new term in a lesson) ---------- */
.term-card {
  position: relative; overflow: hidden;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 32px 30px 30px; text-align: center; margin-bottom: 20px;
  box-shadow: var(--shadow-md); color: var(--ink);
}
.term-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--secondary));
}

.chip {
  display: inline-block; padding: 3px 10px; border-radius: 99px;
  font-size: 0.7rem; font-weight: 600; letter-spacing: 0.03em;
  background: var(--surface-sunken); border: 1px solid var(--border); color: var(--ink-soft);
}
.chip-new { background: var(--accent-tint); border-color: transparent; color: var(--accent); }
.term-chips { display: flex; flex-wrap: wrap; justify-content: center; gap: 6px; margin-bottom: 22px; }

.term-big-row { display: flex; align-items: center; justify-content: center; gap: 12px; flex-wrap: wrap; }
.term-big {
  font-family: var(--font-serif); font-weight: 700; font-size: 2.7rem;
  line-height: 1.1; letter-spacing: -0.015em; margin: 0; overflow-wrap: anywhere;
}
.term-kana { margin-top: 8px; font-size: 1.15rem; letter-spacing: 0.06em; color: var(--ink-soft); }
.term-pron { margin-top: 6px; font-size: 0.95rem; font-style: italic; color: var(--ink-faint); }

/* thin rule with a small ink diamond in the middle — quiet seal motif */
.term-rule { position: relative; height: 1px; max-width: 220px; margin: 26px auto; background: var(--border); }
.term-rule::after {
  content: ''; position: absolute; left: 50%; top: 50%;
  width: 7px; height: 7px; transform: translate(-50%, -50%) rotate(45deg);
  background: var(--surface); border: 1px solid var(--border-strong);
}

.term-label {
  font-size: 0.67rem; font-weight: 700; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: 8px;
}
.term-meaning {
  font-family: var(--font-serif); font-weight: 600; font-size: 1.5rem;
  line-height: 1.3; color: var(--ink);
}

.term-alts { margin-top: 24px; padding-top: 18px; border-top: 1px dashed var(--border); }
.term-alts-label {
  font-size: 0.65rem; font-weight: 700; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: 10px;
}
.term-alt-group { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 6px; margin-bottom: 6px; }
.term-alt-key { font-size: 0.7rem; font-weight: 600; color: var(--ink-faint); }
.alt-chip {
  display: inline-block; padding: 2px 9px; border-radius: 99px; font-size: 0.75rem;
  background: var(--surface-sunken); border: 1px solid var(--border); color: var(--ink-soft);
}

.term-notes {
  margin-top: 22px; padding: 14px 16px; text-align: left;
  background: var(--surface-sunken); border-left: 3px solid var(--secondary);
  border-radius: 0 8px 8px 0; color: var(--ink-soft); font-size: 0.9rem; line-height: 1.55;
}
.term-notes-label {
  display: block; font-size: 0.63rem; font-weight: 700; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: 4px;
}

.session-actions { display: flex; justify-content: center; }
.session-actions .btn { min-width: 220px; }

/* ---------- speaker button (also used in the term list) ---------- */
.speak-btn {
  display: inline-flex; align-items: center; justify-content: center; flex-shrink: 0;
  width: 34px; height: 34px; border-radius: 50%;
  background: var(--surface-sunken); border: 1px solid var(--border); color: var(--ink-soft);
  cursor: pointer; padding: 0;
}
.speak-btn:hover { background: var(--accent-tint); color: var(--accent); border-color: var(--accent); }
.speak-btn .icon { width: 16px; height: 16px; margin: 0; }
.term-cell-row { display: inline-flex; align-items: center; gap: 8px; }
.term-cell-row .speak-btn { width: 26px; height: 26px; }
.term-cell-row .speak-btn .icon { width: 13px; height: 13px; }

/* ---------- quiz card ---------- */
.quiz-card {
  position: relative; overflow: hidden;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px 30px 28px; text-align: center; margin-bottom: 22px;
  box-shadow: var(--shadow-md); color: var(--ink);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.quiz-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: var(--accent); transition: background 0.2s ease;
}
.quiz-card.review::before { background: var(--secondary); }

.quiz-card-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; min-width: 0; margin-bottom: 20px; }
.quiz-tag {
  display: inline-block; padding: 4px 11px; border-radius: 99px;
  font-size: 0.67rem; font-weight: 700; letter-spacing: 0.13em; text-transform: uppercase;
}
.quiz-tag.is-meaning { background: var(--accent-tint); color: var(--accent); }
.quiz-tag.is-term { background: var(--secondary-tint); color: var(--secondary-dark); }

.quiz-lead { font-size: 0.95rem; color: var(--ink-soft); margin: 0 0 14px; }
.quiz-subject-row { display: flex; align-items: center; justify-content: center; gap: 12px; flex-wrap: wrap; }
.quiz-subject {
  font-family: var(--font-serif); font-weight: 700; font-size: 2.15rem;
  line-height: 1.15; letter-spacing: -0.015em; color: var(--ink); overflow-wrap: anywhere;
}
.quiz-subject.is-english { font-size: 1.75rem; }
.quiz-subject-kana { margin-top: 8px; font-size: 1rem; letter-spacing: 0.06em; color: var(--ink-faint); }

.quiz-answer { display: flex; align-items: stretch; gap: 10px; margin-top: 26px; }
.quiz-input {
  flex: 1; min-width: 0; /* without this the input refuses to shrink on narrow screens */
  font-family: var(--font-body); font-size: 1.1rem; font-weight: 500; text-align: center;
  background: var(--surface-sunken); border: 1.5px solid var(--border-strong); color: var(--ink);
  padding: 0.72em 0.9em; border-radius: 9px;
  transition: background 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}
.quiz-input::placeholder { color: var(--ink-faint); font-weight: 400; font-size: 0.92rem; }
.quiz-input:focus { outline: none; background: var(--surface); border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-tint); }
.quiz-card.review .quiz-input:focus { border-color: var(--secondary); box-shadow: 0 0 0 3px var(--secondary-tint); }
.quiz-input:disabled { opacity: 1; }
.quiz-input.shake { animation: input-shake 0.32s ease; border-color: var(--bad); }
@keyframes input-shake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-7px); }
  40% { transform: translateX(6px); }
  60% { transform: translateX(-4px); }
  80% { transform: translateX(3px); }
}
.quiz-submit { flex-shrink: 0; display: inline-flex; align-items: center; gap: 7px; padding: 0.7em 1.3em; }
.quiz-submit .icon { width: 16px; height: 16px; margin: 0; }
.quiz-card.review .quiz-submit { background: var(--secondary); }
.quiz-card.review .quiz-submit:hover:not(:disabled) { background: var(--secondary-dark); }

.quiz-feedback {
  min-height: 1.8em; margin-top: 14px; font-size: 0.92rem; font-weight: 600;
  display: flex; align-items: center; justify-content: center; gap: 7px;
}
.quiz-feedback .ok, .quiz-feedback .bad { display: inline-flex; align-items: center; gap: 7px; animation: fb-in 0.22s ease; }
.quiz-feedback .icon { width: 16px; height: 16px; stroke-width: 2.4; margin: 0; }
.quiz-feedback .ok { color: var(--ok); }
.quiz-feedback .bad { color: var(--bad); }
.quiz-enter-hint { font-size: 0.76rem; font-weight: 500; color: var(--ink-faint); }
@keyframes fb-in { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }

/* answered states — the card itself reacts, no answer is ever revealed */
.quiz-card.is-correct { border-color: var(--ok); box-shadow: var(--shadow-md), 0 0 0 3px rgba(46, 125, 79, 0.15); }
.quiz-card.is-correct::before { background: var(--ok); }
.quiz-card.is-wrong {
  border-color: var(--bad); box-shadow: var(--shadow-md), 0 0 0 3px rgba(184, 84, 29, 0.15);
  animation: card-nudge 0.34s ease;
}
.quiz-card.is-wrong::before { background: var(--bad); }
@keyframes card-nudge {
  0%, 100% { transform: translateX(0); }
  22% { transform: translateX(-6px); }
  48% { transform: translateX(5px); }
  74% { transform: translateX(-3px); }
}

/* ---------- session intro (before you start) ---------- */
.session-intro {
  --tone: var(--accent); --tone-tint: var(--accent-tint);
  max-width: 520px; margin: 44px auto; text-align: center;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-md); padding: 38px 32px 34px;
}
.session-intro[data-tone="secondary"] { --tone: var(--secondary); --tone-tint: var(--secondary-tint); }
.intro-icon {
  width: 54px; height: 54px; border-radius: 50%; margin: 0 auto 18px;
  display: flex; align-items: center; justify-content: center;
  background: var(--tone-tint); color: var(--tone);
}
.intro-icon .icon { width: 26px; height: 26px; margin: 0; }
.session-intro h1 { font-size: 1.8rem; margin-bottom: 8px; }
.session-intro p { color: var(--ink-soft); margin: 0 0 20px; line-height: 1.55; }
.session-intro .intro-note { font-size: 0.86rem; color: var(--ink-faint); margin-bottom: 24px; }

.intro-steps { display: grid; gap: 11px; text-align: left; margin: 24px 0 28px; }
.intro-step { display: flex; align-items: center; gap: 12px; font-size: 0.92rem; color: var(--ink-soft); }
.intro-step-num {
  flex-shrink: 0; width: 26px; height: 26px; border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--tone-tint); color: var(--tone);
  font-family: var(--font-mono); font-size: 0.78rem; font-weight: 600;
}
.intro-stats { display: flex; justify-content: center; gap: 12px; margin: 24px 0 18px; }
.intro-stat {
  flex: 1; min-width: 0; max-width: 150px; padding: 14px 10px; border-radius: 9px;
  background: var(--surface-sunken); border: 1px solid var(--border);
}
.intro-stat-num { display: block; font-family: var(--font-mono); font-size: 1.6rem; font-weight: 600; color: var(--ink); }
.intro-stat-label { display: block; margin-top: 2px; font-size: 0.68rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-faint); }

/* ---------- session summary (after you finish) ---------- */
.session-summary {
  max-width: 520px; margin: 44px auto; text-align: center;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-md); padding: 34px 30px 30px;
}
.summary-ring-wrap { display: flex; justify-content: center; margin-bottom: 16px; }
.summary-ring { width: 132px; height: 132px; }
.summary-ring-wrap[data-tone="great"] .ring-fill { stroke: var(--ok); }
.summary-ring-wrap[data-tone="good"] .ring-fill { stroke: var(--secondary); }
.summary-ring-wrap[data-tone="okay"] .ring-fill { stroke: var(--accent); }
.summary-seal {
  width: 60px; height: 60px; border-radius: 50%; margin: 0 auto 16px;
  display: flex; align-items: center; justify-content: center;
  background: var(--accent-tint); color: var(--accent);
}
.summary-seal .icon { width: 28px; height: 28px; margin: 0; }
.session-summary h1 { font-size: 1.85rem; margin-bottom: 8px; }
.summary-blurb { color: var(--ink-soft); margin: 0 0 18px; line-height: 1.55; }
.summary-note { margin: 10px 0; }
.summary-belt-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 6px; margin-bottom: 4px; }
.summary-term-chip {
  padding: 4px 11px; border-radius: 99px; font-size: 0.82rem; font-weight: 500;
  background: var(--surface-sunken); border: 1px solid var(--border); color: var(--ink-soft);
}
.summary-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin-top: 22px; }

/* briefly marks the admin table row that just changed, so a save/approve
   lands visibly instead of silently refreshing the list underneath you */
@keyframes row-flash {
  0%   { background: var(--accent-tint); }
  70%  { background: var(--accent-tint); }
  100% { background: transparent; }
}
.row-flash > td { animation: row-flash 1.8s ease-out; }
@media (prefers-reduced-motion: reduce) {
  .row-flash > td { animation: none; background: var(--accent-tint); }
}

/* ---------- term disambiguation label ---------- */
/* Shown beside a quiz prompt when two terms can't be told apart from the
   prompt alone. Deliberately quiet: it's context, not part of the question. */
.quiz-context {
  display: inline-block; padding: 3px 10px; border-radius: 99px;
  font-size: 0.78rem; font-weight: 600; letter-spacing: 0.02em;
  background: var(--surface-sunken); border: 1px dashed var(--border-strong);
  color: var(--ink-faint); vertical-align: middle;
}
.chip-context { background: var(--secondary-tint); border-color: transparent; color: var(--secondary-dark); }

.field-hint {
  display: block; margin-top: 5px; font-size: 0.78rem;
  line-height: 1.45; color: var(--ink-faint); font-weight: 400;
}

/* ---------- sticking points (per-student trouble terms) ---------- */
.trouble-section { margin-top: 40px; }
.trouble-section h2 { font-size: 1.2rem; margin-bottom: 6px; }
.trouble-intro { font-size: 0.85rem; margin-bottom: 14px; line-height: 1.5; }
.trouble-empty { font-size: 0.88rem; margin: 6px 0 0; }

.trouble-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.trouble-item {
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 12px; min-width: 0;
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px;
  box-shadow: var(--shadow-sm); padding: 13px 16px;
  border-left: 3px solid var(--secondary);
}
.trouble-main { min-width: 0; flex: 1 1 200px; }
.trouble-term-row { display: flex; align-items: center; gap: 9px; flex-wrap: wrap; min-width: 0; }
.trouble-term { font-family: var(--font-body); font-weight: 700; font-size: 1.02rem; color: var(--ink); }
.trouble-term-row .speak-btn { width: 26px; height: 26px; }
.trouble-term-row .speak-btn .icon { width: 13px; height: 13px; }
.trouble-meaning { font-size: 0.86rem; color: var(--ink-soft); margin-top: 2px; }
.trouble-stats { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; flex-shrink: 0; }
.trouble-misses {
  font-family: var(--font-mono); font-size: 0.72rem; font-weight: 600;
  padding: 3px 9px; border-radius: 20px;
  background: var(--accent-tint); color: var(--accent);
}
.trouble-dir { font-size: 0.72rem; color: var(--ink-faint); }
.trouble-acc { font-family: var(--font-mono); font-size: 0.72rem; color: var(--ink-faint); }

.user-detail-trouble { margin-top: 22px; padding-top: 18px; border-top: 1px solid var(--border); }
.user-detail-trouble h4 { font-size: 1rem; margin: 0 0 4px; }

@media (max-width: 560px) {
  .trouble-item { flex-direction: column; align-items: flex-start; }
  .trouble-stats { width: 100%; }
}

/* ---------- admin: content data health ---------- */
.health-panel {
  margin-bottom: 14px; padding: 14px 16px; border-radius: 10px;
  background: var(--surface); border: 1px solid var(--border);
}
.health-panel.has-blocking { border-color: var(--bad); }
.health-panel.is-clean {
  display: flex; align-items: center; gap: 10px;
  font-size: 0.88rem; color: var(--ok); border-color: var(--ok);
}
.health-panel.is-clean .icon { width: 17px; height: 17px; flex-shrink: 0; margin: 0; }
.health-panel > summary {
  cursor: pointer; font-weight: 600; font-size: 0.92rem; color: var(--ink); list-style: none;
}
.health-panel > summary::-webkit-details-marker { display: none; }
.health-panel > summary::before { content: '\25B8'; display: inline-block; margin-right: 8px; transition: transform 0.15s ease; }
.health-panel[open] > summary::before { transform: rotate(90deg); }
.health-list { list-style: none; padding: 0; margin: 14px 0 0; display: grid; gap: 10px; }
.health-item {
  padding: 10px 12px; border-radius: 8px;
  background: var(--surface-sunken); border: 1px solid var(--border);
  border-left: 3px solid var(--border-strong);
}
.health-item.sev-bad { border-left-color: var(--bad); }
.health-item.sev-warn { border-left-color: var(--secondary); }
.health-item.sev-info { border-left-color: var(--border-strong); }
.health-head { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; }
.health-label { font-weight: 700; font-size: 0.9rem; }
.health-count { font-family: var(--font-mono); font-size: 0.74rem; color: var(--ink-faint); flex-shrink: 0; }
.health-why { font-size: 0.8rem; color: var(--ink-faint); margin: 4px 0 9px; line-height: 1.45; }
.health-terms { display: flex; flex-wrap: wrap; gap: 6px; }
.health-term {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 2px 4px 2px 6px; border-radius: 7px; font-size: 0.82rem;
  background: var(--surface); border: 1px solid var(--border); color: var(--ink-soft);
}
.health-term .icon-btn-sm { padding: 3px 5px; border: none; }
.health-more { align-self: center; font-size: 0.78rem; color: var(--ink-faint); }

.chart-note { font-size: 0.78rem; color: var(--ink-faint); line-height: 1.5; margin: -8px 0 14px; }

/* ---------- admin: term collision warnings ---------- */
.collision-panel {
  margin-bottom: 18px; padding: 14px 16px; border-radius: 10px;
  background: var(--surface); border: 1px solid var(--border);
}
.collision-panel.has-unresolved { border-color: var(--secondary); background: var(--secondary-tint); }
.collision-panel > summary {
  cursor: pointer; font-weight: 600; font-size: 0.92rem; color: var(--ink);
  list-style: none;
}
.collision-panel > summary::-webkit-details-marker { display: none; }
.collision-panel > summary::before { content: '\25B8'; display: inline-block; margin-right: 8px; transition: transform 0.15s ease; }
.collision-panel[open] > summary::before { transform: rotate(90deg); }
.collision-note { font-size: 0.84rem; margin: 10px 0 14px; }
.collision-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; }
.collision-item { padding: 10px 12px; border-radius: 8px; background: var(--surface); border: 1px solid var(--border); }
.collision-item.is-resolved { opacity: 0.72; }
.collision-head { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 8px; }
.collision-word { font-weight: 700; }
.collision-kind { font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-faint); }
.collision-warn {
  font-size: 0.72rem; font-weight: 700; padding: 2px 8px; border-radius: 99px;
  background: var(--bad); color: #fff;
}
.collision-ok { display: inline-flex; align-items: center; gap: 4px; font-size: 0.72rem; font-weight: 600; color: var(--ok); }
.collision-ok .icon { width: 13px; height: 13px; margin: 0; }
.collision-terms { display: grid; gap: 6px; }
.collision-term {
  display: flex; flex-wrap: wrap; align-items: center; gap: 8px;
  font-size: 0.86rem; color: var(--ink-soft); min-width: 0;
}
.collision-lvl {
  flex-shrink: 0; font-family: var(--font-mono); font-size: 0.72rem;
  padding: 1px 6px; border-radius: 5px;
  background: var(--surface-sunken); border: 1px solid var(--border); color: var(--ink-faint);
}
.collision-ctx { font-style: normal; font-size: 0.76rem; padding: 1px 8px; border-radius: 99px; background: var(--secondary-tint); color: var(--secondary-dark); }
.collision-ctx.missing { background: transparent; border: 1px dashed var(--border-strong); color: var(--ink-faint); }
.collision-term .icon-btn-sm { margin-left: auto; flex-shrink: 0; }

.empty-state { max-width: 480px; margin: 70px auto; text-align: center; }
.empty-state h1 { font-size: 2rem; }
.empty-state p { color: var(--ink-soft); margin-bottom: 22px; }

@media (max-width: 900px) {
  .shell { flex-direction: column; }
  .sidebar {
    width: 100%; max-width: 100%; height: auto; position: sticky; top: 0;
    flex-direction: row; align-items: center; justify-content: space-between;
    padding: 12px 16px;
    border-right: none; border-bottom: 1px solid var(--border);
    overflow-x: hidden;
  }
  .sidebar .brand { margin-bottom: 0; padding: 0; flex-shrink: 0; }

  /* Nav becomes a fixed bottom tab bar — a proven, thumb-friendly mobile
     pattern — instead of squeezing icons into the same row as the brand
     and account controls, which left it a barely-usable sliver. Being
     `position: fixed`, it lifts clean out of the sidebar's row layout
     regardless of where it sits in the HTML. */
  .sidebar nav {
    position: fixed; left: 0; right: 0; bottom: 0;
    flex-direction: row; justify-content: space-around; align-items: stretch;
    gap: 0; min-width: 0;
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 6px 4px calc(6px + env(safe-area-inset-bottom, 0px));
    z-index: 5;
    overflow-x: auto;
  }
  .sidebar nav a {
    flex-direction: column; justify-content: center; gap: 3px;
    padding: 6px 2px; border-radius: 8px;
    font-size: 0.6rem; letter-spacing: -0.01em; text-align: center;
    flex: 1 1 0; min-width: 0; max-width: 84px;
  }
  /* short labels only on mobile — 7 tabs (admin) leaves ~48px each, and
     "Leaderboard" at that width runs straight into its neighbours */
  .sidebar nav a span.nav-label { display: none; }
  .sidebar nav a span.nav-label-short {
    display: block; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
    max-width: 100%;
  }
  .sidebar nav a .icon { width: 21px; height: 21px; margin: 0 auto; }

  .sidebar-footer { flex-direction: row; margin-top: 0; padding-top: 0; border-top: none; flex-shrink: 0; }
  .sidebar-footer .btn { width: auto; }

  /* extra bottom padding so page content never sits underneath the fixed tab bar */
  .content { padding: 28px 20px calc(84px + env(safe-area-inset-bottom, 0px)); }
}

@media (max-width: 720px) {
  .hero-row { grid-template-columns: 1fr; }
  .action-cards { grid-template-columns: 1fr; }
  .chart-grid { grid-template-columns: minmax(0, 1fr); }
  .form-grid { grid-template-columns: minmax(0, 1fr); }
  .admin-subnav { flex-wrap: wrap; }
}

/* The 3x3 belt grid works on a wide screen but reads badly on a phone: nine
   near-identical cards, most of them zero, in a block that doesn't match the
   full-width sections above and below it. Centering wouldn't help — the
   mismatch is the grid itself. So on narrow screens it becomes one card of
   nine rows: swatch, belt name, count. Same information, scannable in one
   vertical pass, and consistent with the "tables become rows" pattern used
   everywhere else on mobile. */
@media (max-width: 640px) {
  .belt-row {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
  }
  .belt-col {
    display: flex; align-items: center; gap: 13px;
    text-align: left; padding: 11px 15px;
    background: none; border: none; border-radius: 0; box-shadow: none;
    border-bottom: 1px solid var(--border);
  }
  .belt-col:last-child { border-bottom: none; }
  /* dimming the whole row would read as "disabled" rather than "empty", so
     only the swatch softens */
  .belt-col.is-empty { opacity: 1; }
  .belt-col.is-empty .belt-swatch { opacity: 0.3; }

  /* markup order is count → swatch → label, so reorder rather than rewrite it */
  .belt-swatch { order: 1; flex-shrink: 0; width: 6px; height: 22px; border-radius: 3px; margin: 0; }
  .belt-label { order: 2; flex: 1 1 auto; min-width: 0; font-size: 0.9rem; color: var(--ink); }
  .belt-count { order: 3; flex-shrink: 0; font-size: 1rem; }

  /* the admin per-student rack is already inside a card — nesting card chrome
     inside card chrome looks like a mistake */
  .user-detail-card .belt-row {
    background: none; border: none; box-shadow: none; border-radius: 0;
  }
  .belt-col.mini { width: auto; padding: 9px 2px; }
  .belt-col.mini .belt-label { font-size: 0.85rem; }
  .belt-col.mini .belt-count { font-size: 0.95rem; }
}

/* stack the answer row before the input gets squashed */
@media (max-width: 560px) {
  .quiz-answer { flex-direction: column; }
  .quiz-submit { width: 100%; justify-content: center; }
  .session-actions .btn { min-width: 0; width: 100%; }
  .summary-actions .btn { width: 100%; }
}

@media (max-width: 480px) {
  .content { padding: 20px 14px calc(84px + env(safe-area-inset-bottom, 0px)); }
  .brand-title { font-size: 0.92rem; }
  .brand-sub { font-size: 0.6rem; }
  .sidebar-footer .btn { padding: 0.5em 0.9em; font-size: 0.85rem; }
  .auth-card { padding: 28px 22px; }
  .auth-brand h1 { font-size: 1.7rem; }
  .term-card { padding: 26px 18px 24px; }
  .quiz-card { padding: 20px 18px 24px; }
  .term-big { font-size: 2rem; }
  .term-meaning { font-size: 1.3rem; }
  .quiz-subject { font-size: 1.8rem; }
  .quiz-subject.is-english { font-size: 1.5rem; }
  .session-intro, .session-summary { margin: 26px auto; padding: 28px 20px 26px; }
  .session-intro h1, .session-summary h1 { font-size: 1.55rem; }
  .empty-state { margin: 44px auto; }
  .empty-state h1 { font-size: 1.6rem; }
  .chart-card { padding: 14px; }
  .chart-canvas-wrap { height: 190px; }
  .hero-card h1 { font-size: 1.5rem; }
}

@media (prefers-reduced-motion: reduce) {
  .btn, .action-card { transition: none; }
  .quiz-input.shake { animation: none; }
  .quiz-card.is-wrong { animation: none; }
  .quiz-feedback .ok, .quiz-feedback .bad { animation: none; }
  .session-track-fill { transition: none; }
}

/* ================= DARK MODE ================= */
:root[data-theme="dark"] {
  --bg: #15110c;
  --surface: #1e1811;
  --surface-sunken: #261e15;
  --border: #362b1d;
  --border-strong: #493a26;

  --ink: #f3ecdc;
  --ink-soft: #c9bda3;
  --ink-faint: #8f8368;

  --accent: #e0564a;
  --accent-dark: #c24438;
  --accent-tint: rgba(224, 86, 74, 0.15);
  --secondary: #c9a227;
  --secondary-dark: #a9871f;
  --secondary-tint: rgba(201, 162, 39, 0.15);

  --belt-white: #ede6d3;
  --belt-black: #d7cbb0;

  --ok: #5fbe7c;
  --bad: #e98a6a;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.35);
  --shadow-md: 0 10px 28px rgba(0,0,0,0.45);
}
:root[data-theme="dark"] .auth-screen {
  background: radial-gradient(circle at 12% 8%, rgba(224,86,74,0.09), transparent 42%), radial-gradient(circle at 88% 92%, rgba(201,162,39,0.09), transparent 42%), var(--bg);
}
:root[data-theme="dark"] .levelup-banner,
:root[data-theme="dark"] .levelup-inline { background: #3a2f10; color: #f1cf6a; border-color: #574a17; }
:root[data-theme="dark"] .badge-pill.admin { background: #3a2f10; color: #f1cf6a; }
:root[data-theme="dark"] .badge-pill.active { background: #163a2a; color: #63d99a; }
:root[data-theme="dark"] .badge-pill.inactive { background: #3a1e1a; color: #f2836a; }

/* the teaching/quiz cards stay warm parchment even in dark mode — a small
   nod to the flashcard-on-black look, and it keeps the "no hint" quiz
   feedback colors legible without a second set of rules */
:root[data-theme="dark"] .term-card,
:root[data-theme="dark"] .quiz-card {
  --surface: #fffdf8;
  --surface-sunken: #efe6d1;
  --border: #e1d4b3;
  --border-strong: #cbb98f;
  --ink: #241d14;
  --ink-soft: #5c5240;
  --ink-faint: #8f8368;
  --accent: #a6332b;
  --accent-dark: #872822;
  --accent-tint: #f3e0dc;
  /* reviews run on ochre, so these need the light-theme values too or the
     review stripe / tag / submit button go neon against the parchment */
  --secondary: #8a6d2e;
  --secondary-dark: #715a25;
  --secondary-tint: #f1e8d2;
  --ok: #2e7d4f;
  --bad: #b8541d;
}

html { transition: background 0.15s ease; }
.shell, .auth-card, .term-card, .quiz-card, .hero-card, .progress-card, .action-card, .belt-col, .level-section, .settings-section, .stat-card {
  transition: background 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}

/* ---------- icon button (theme toggle etc) ---------- */
.icon-btn { padding: 0.6em 0.75em; }
.icon-btn-sm { background: transparent; border: 1px solid var(--border); border-radius: 6px; padding: 7px 9px; cursor: pointer; color: var(--ink-soft); }
.icon-btn-sm:hover { background: var(--surface-sunken); color: var(--ink); }
.icon-btn-sm.danger:hover { color: var(--bad); border-color: var(--bad); }
.icon-btn-sm .icon, .icon-btn .icon { margin: 0; }

/* ---------- progress ring (dashboard) ---------- */
.progress-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); display: flex; flex-direction: column; align-items: center;
  justify-content: center; padding: 18px;
}
.progress-ring { width: 130px; height: 130px; }
.ring-track { fill: none; stroke: var(--surface-sunken); stroke-width: 9; }
.ring-fill { fill: none; stroke: var(--accent); stroke-width: 9; stroke-linecap: round; transform: rotate(-90deg); transform-origin: 55px 55px; transition: stroke-dashoffset 0.5s ease; }
.ring-pct { font-family: var(--font-body); font-size: 20px; font-weight: 700; fill: var(--ink); text-anchor: middle; }
.ring-sub { font-family: var(--font-mono); font-size: 9px; fill: var(--ink-faint); text-anchor: middle; }
.progress-caption { margin-top: 10px; font-size: 0.8rem; color: var(--ink-faint); font-weight: 500; }

.hero-row { grid-template-columns: 1.3fr 0.8fr; }

/* ---------- settings ---------- */
.settings-section {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); padding: 24px 26px; margin-bottom: 20px; max-width: 620px;
}
.settings-section h2 { font-size: 1.1rem; margin-bottom: 14px; }
.settings-form { display: flex; flex-direction: column; gap: 14px; }
.settings-form label { display: flex; flex-direction: column; gap: 6px; font-size: 0.83rem; color: var(--ink-soft); font-weight: 500; }
.settings-form input, .settings-form select, .settings-form textarea {
  font-family: var(--font-body); background: var(--surface); border: 1px solid var(--border-strong);
  color: var(--ink); padding: 0.6em 0.8em; border-radius: 7px; font-size: 0.95rem;
}
.settings-form input:focus, .settings-form select:focus, .settings-form textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-tint); }
.settings-form textarea { font-family: var(--font-mono); font-size: 0.85rem; resize: vertical; }
.settings-form input[type="file"] { border: 1px dashed var(--border-strong); background: var(--surface-sunken); padding: 0.5em 0.7em; }
.bulk-import-form code { background: var(--surface); border: 1px solid var(--border); padding: 1px 5px; border-radius: 4px; font-family: var(--font-mono); font-size: 0.85em; }
.form-actions { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.save-msg { font-size: 0.85rem; }
.save-msg.ok { color: var(--ok); }
.save-msg.bad { color: var(--bad); }

.theme-radio-row { display: flex; gap: 18px; }
.theme-radio { display: flex; align-items: center; gap: 7px; font-size: 0.9rem; color: var(--ink-soft); cursor: pointer; }

.warning-zone { border-color: var(--secondary); }
.btn-warning { background: var(--secondary); color: #fff; }
.btn-warning:hover:not(:disabled) { background: var(--secondary-dark); }

.danger-zone { border-color: var(--bad); }
.btn-danger { background: var(--bad); color: #fff; }
.btn-danger:hover:not(:disabled) { opacity: 0.9; }

/* ---------- admin ---------- */
.admin-subnav { display: flex; gap: 8px; margin: 18px 0 22px; }
.admin-tab-btn {
  display: flex; align-items: center; gap: 7px; background: var(--surface); border: 1px solid var(--border);
  color: var(--ink-soft); font-family: var(--font-body); font-weight: 600; padding: 8px 16px;
  border-radius: 8px; cursor: pointer; font-size: 0.9rem;
}
.admin-tab-btn.active { color: var(--accent); border-color: var(--accent); background: var(--accent-tint); }
.admin-toolbar { margin-bottom: 16px; display: flex; gap: 10px; flex-wrap: wrap; }
.admin-toolbar .btn { display: inline-flex; align-items: center; gap: 6px; }
.admin-table { min-width: 640px; }
.admin-table th { text-align: left; font-family: var(--font-mono); font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--ink-faint); padding: 8px 6px; }
.table-actions { display: flex; gap: 6px; white-space: nowrap; }
.btn-xs { font-size: 0.78rem; padding: 0.5em 0.9em; }

/* On mobile, tables restack as cards (one per row) instead of needing
   horizontal scrolling — each cell becomes a labeled line using its
   data-label attribute. */
@media (max-width: 640px) {
  .level-section { overflow-x: visible; padding: 4px; }
  .term-table, .admin-table { min-width: 0; width: 100%; }
  .term-table thead, .admin-table thead { display: none; }
  .term-table tr, .admin-table tr {
    display: block;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 9px;
    padding: 10px 12px;
    margin: 8px 0;
  }
  .term-table tr.locked { opacity: 0.5; }
  .term-table td, .admin-table td {
    display: flex; align-items: center; justify-content: space-between; gap: 12px;
    padding: 7px 0; border-top: 1px solid var(--border); text-align: right;
  }
  .term-table td:first-child, .admin-table td:first-child { border-top: none; }
  .term-table td::before, .admin-table td::before {
    content: attr(data-label);
    font-family: var(--font-mono); font-size: 0.66rem; text-transform: uppercase;
    letter-spacing: 0.05em; color: var(--ink-faint); text-align: left; flex-shrink: 0;
  }
  .term-cell { width: auto; }
  .table-actions { justify-content: flex-end; flex-wrap: wrap; }
}

.term-form { background: var(--surface-sunken); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; margin-bottom: 20px; min-width: 0; }
.form-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 14px; }
.form-grid label { display: flex; flex-direction: column; gap: 6px; font-size: 0.83rem; color: var(--ink-soft); font-weight: 500; min-width: 0; }
.form-grid input { font-family: var(--font-body); background: var(--surface); border: 1px solid var(--border-strong); color: var(--ink); padding: 0.55em 0.75em; border-radius: 7px; width: 100%; max-width: 100%; }

.badge-pill { display: inline-block; font-size: 0.72rem; font-weight: 600; padding: 3px 10px; border-radius: 12px; }
.badge-pill.admin { background: #f6ecd3; color: #6b5410; }
.badge-pill.active { background: #e3f0e6; color: #187a4c; }
.badge-pill.inactive { background: #f6e2d8; color: #a63b1f; }

.link-btn {
  background: none; border: none; padding: 0; margin: 0; cursor: pointer;
  color: inherit; font: inherit; text-decoration: underline; text-decoration-color: var(--border-strong);
}
.link-btn:hover { color: var(--accent); text-decoration-color: var(--accent); }

.pending-section { border-color: var(--secondary); }
.pending-section h3 { display: flex; align-items: center; gap: 8px; }
.pending-section h3 .muted {
  font-family: var(--font-mono); font-size: 0.7rem; background: var(--secondary-tint);
  color: var(--secondary-dark); padding: 1px 8px; border-radius: 10px;
}

.user-detail-card { border-color: var(--accent); }
.user-detail-header { display: flex; align-items: center; justify-content: space-between; margin: 14px 0 10px; }
.user-detail-header h3 { margin: 0; }
.user-detail-meta { margin: 14px 0; font-size: 0.85rem; }
.belt-col.mini { width: 76px; padding: 8px 4px; }
.belt-col.mini .belt-count { font-size: 0.9rem; }
.belt-col.mini .belt-label { font-size: 0.6rem; }

.stat-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 14px; }
.stat-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow-sm); padding: 20px; text-align: center; }
.stat-num { font-family: var(--font-body); font-size: 2rem; font-weight: 700; color: var(--accent); }
.stat-label { font-size: 0.78rem; color: var(--ink-faint); margin-top: 4px; }

/* ---------- admin stats charts ---------- */
.chart-toolbar { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 10px; margin: 26px 0 14px; }
.range-switch { display: flex; gap: 6px; }
.range-switch button {
  background: var(--surface); border: 1px solid var(--border); color: var(--ink-soft);
  font-family: var(--font-body); font-weight: 600; font-size: 0.82rem;
  padding: 6px 14px; border-radius: 7px; cursor: pointer;
}
.range-switch button.active { color: var(--accent); border-color: var(--accent); background: var(--accent-tint); }
.range-switch button:hover:not(.active) { background: var(--surface-sunken); }

.chart-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 16px; margin-bottom: 30px; }
.chart-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow-sm); padding: 18px 20px; min-width: 0; }
.chart-card.wide { grid-column: 1 / -1; }
.chart-card h3 { font-size: 0.92rem; margin-bottom: 14px; color: var(--ink-soft); }
.chart-canvas-wrap { position: relative; height: 220px; min-width: 0; }
.chart-card.wide .chart-canvas-wrap { height: 280px; }

/* ---------- gamification: points, leaderboard, achievements ---------- */
.hero-points {
  display: inline-flex; align-items: center; gap: 8px; width: fit-content;
  margin-top: 16px; padding: 6px 14px; border-radius: 20px;
  background: var(--secondary-tint); color: var(--secondary-dark);
  font-family: var(--font-body); font-weight: 700; font-size: 0.95rem;
}
.hero-points .icon { color: var(--secondary); }

.lb-rank { font-family: var(--font-mono); font-size: 1.1rem; width: 40px; text-align: center; }
.lb-points { font-family: var(--font-mono); font-weight: 700; color: var(--secondary-dark); }
.admin-table tr.me { background: var(--accent-tint); }
.admin-table tr.me .term-cell { color: var(--accent); }

.achievement-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 12px; margin: 12px 0 20px; }
.achievement-card {
  background: var(--surface-sunken); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 16px; text-align: center; opacity: 0.55;
}
.achievement-card.unlocked { opacity: 1; background: var(--surface); box-shadow: var(--shadow-sm); border-color: var(--secondary); }
.achievement-icon { color: var(--ink-faint); margin-bottom: 6px; }
.achievement-card.unlocked .achievement-icon { color: var(--secondary); }
.achievement-name { font-family: var(--font-body); font-weight: 700; font-size: 0.95rem; }
.achievement-desc { font-size: 0.78rem; margin: 6px 0; min-height: 2.2em; }
.achievement-progress { font-family: var(--font-mono); font-size: 0.75rem; color: var(--ink-faint); }
.achievement-card.unlocked .achievement-progress { color: var(--secondary-dark); font-weight: 600; }

.achievement-banner {
  display: flex; align-items: center; gap: 10px; text-align: left;
  background: var(--secondary-tint); color: var(--secondary-dark); border: 1px solid var(--secondary);
  border-radius: 8px; padding: 12px 16px; margin: 0 0 14px;
}
.achievement-banner .icon { flex-shrink: 0; color: var(--secondary); }

/* ---------- install prompt banner ---------- */
.install-banner {
  position: fixed; left: 16px; right: 16px; bottom: 16px;
  z-index: 50; max-width: 480px; margin: 0 auto;
  display: flex; align-items: center; gap: 12px;
  background: var(--surface); border: 1px solid var(--border); border-radius: 12px;
  box-shadow: var(--shadow-md); padding: 14px 16px;
}
.install-banner > .icon { flex-shrink: 0; color: var(--accent); width: 24px; height: 24px; }
.install-text { display: flex; flex-direction: column; gap: 2px; flex: 1; min-width: 0; }
.install-text strong { font-family: var(--font-body); font-size: 0.92rem; }
.install-text span { font-size: 0.8rem; color: var(--ink-faint); }
.install-banner .install-go { flex-shrink: 0; }
.install-banner .install-dismiss {
  flex-shrink: 0; padding: 4px 8px; font-size: 1.1rem; line-height: 1; border: none;
}
@media (max-width: 900px) {
  .install-banner { bottom: calc(78px + env(safe-area-inset-bottom, 0px)); }
}