/* VidyaGloss — mobile-first. */
:root {
  --bg: #fdfaf6;
  --fg: #1f1a17;
  --muted: #7a6f66;
  --card: #ffffff;
  --line: #e8e0d6;
  --accent: #c2410c;
  --accent-soft: #fde7da;
  --good: #15803d;
  --good-soft: #dcfce7;
  --bad: #b91c1c;
  --bad-soft: #fee2e2;
  /* SRS grades: Again red, Hard amber, Good green, Easy blue. */
  --g-again: #b91c1c; --g-again-bg: #fee2e2;
  --g-hard: #92400e; --g-hard-bg: #fef3c7;
  --g-good: #166534; --g-good-bg: #dcfce7;
  --g-easy: #1e40af; --g-easy-bg: #dbeafe;
  /* Noun gender: masculine blue-green, feminine rose. */
  --m-bg: #e3f1f6; --m-card: #f2f9fc; --m-fg: #0e4a5c;
  --f-bg: #fbe6ee; --f-card: #fdf3f7; --f-fg: #7a1840;
  --radius: 14px;
  --deva-font: "Noto Sans Devanagari", "Kohinoor Devanagari", "Devanagari Sangam MN", "Mangal", system-ui, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #171412;
    --fg: #f3ede7;
    --muted: #a99e94;
    --card: #221e1b;
    --line: #3a332d;
    --accent: #fb923c;
    --accent-soft: #3b2417;
    --good: #4ade80;
    --good-soft: #14321f;
    --bad: #f87171;
    --bad-soft: #3a1a1a;
    --g-again: #fca5a5; --g-again-bg: #451a1a;
    --g-hard: #fcd34d; --g-hard-bg: #42300d;
    --g-good: #86efac; --g-good-bg: #12331f;
    --g-easy: #93c5fd; --g-easy-bg: #172a4d;
    --m-bg: #12303a; --m-card: #173b47; --m-fg: #a5dcef;
    --f-bg: #3a1a28; --f-card: #472131; --f-fg: #f5b3cf;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 18px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
  -webkit-tap-highlight-color: transparent;
}
.loading { padding: 40px 16px; text-align: center; color: var(--muted); }
.shell { max-width: 560px; margin: 0 auto; min-height: 100vh; display: flex; flex-direction: column; }
.main { flex: 1; padding: 0 16px 24px; }
h1 { font-size: 1.5rem; margin: 16px 0 12px; line-height: 1.3; }
h2 { font-size: 1.15rem; margin: 20px 0 8px; color: var(--muted); }
h3 { font-size: 1.05rem; margin: 18px 0 8px; }
p { margin: 8px 0; }
a { color: var(--accent); }

/* Top bar */
.topbar {
  position: sticky; top: 0; z-index: 10;
  display: flex; gap: 4px; align-items: center;
  padding: 8px 8px; padding-top: max(8px, env(safe-area-inset-top));
  background: var(--bg); border-bottom: 1px solid var(--line);
}
.tabs { display: flex; gap: 4px; flex: 1; overflow-x: auto; }
.tab {
  font: inherit; font-size: 0.95rem; border: 0; background: none; color: var(--muted);
  padding: 10px 10px; min-height: 44px; border-radius: 10px; cursor: pointer; white-space: nowrap;
}
.tab.active { color: var(--accent); background: var(--accent-soft); font-weight: 600; }
.iast-toggle { font-family: var(--deva-font); border: 1px solid var(--line); }
.iast-toggle.on { background: var(--accent); color: #fff; border-color: var(--accent); }
.footer { padding: 16px; text-align: center; color: var(--muted); font-size: 0.9rem; padding-bottom: max(16px, env(safe-area-inset-bottom)); }
.link { font: inherit; background: none; border: 0; color: var(--muted); text-decoration: underline; padding: 8px; cursor: pointer; }

/* Buttons */
.btn {
  font: inherit; color: var(--fg); background: var(--card);
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 12px 16px; min-height: 48px; cursor: pointer;
  touch-action: manipulation;
}
.btn:disabled { opacity: 0.5; cursor: default; }
.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); font-weight: 600; }
.btn.danger { color: var(--bad); border-color: var(--bad); }
.btn.wide { display: block; width: 100%; margin: 12px 0; }
.btn.back { border: 0; background: none; padding: 8px 0; color: var(--accent); min-height: 40px; }
.list { display: flex; flex-direction: column; gap: 8px; }
.btn.row { display: flex; justify-content: space-between; align-items: center; text-align: left; gap: 12px; width: 100%; }
.btn.row.locked { opacity: 0.55; }
.row-meta { color: var(--muted); white-space: nowrap; }
.notice { background: var(--accent-soft); border-radius: 10px; padding: 10px 12px; margin: 12px 0; font-size: 0.9rem; }
.save-error { margin: 8px 16px 0; padding: 10px 12px; border-radius: 10px; background: var(--bad-soft); color: var(--bad); font-size: 0.9rem; }
.tip { color: var(--muted); font-size: 0.85rem; margin: 12px 0; }

/* Hindi text: Devanagari, IAST on hover (real hover only) or tap. */
.hi { position: relative; display: inline-block; font-family: var(--deva-font); cursor: pointer; }
.hi .deva { border-bottom: 1px dotted var(--muted); }
.btn .hi .deva, .tab .hi .deva { border-bottom: 0; }
.hi .iast {
  position: absolute; left: 50%; bottom: 100%; transform: translateX(-50%);
  margin-bottom: 4px; padding: 3px 8px; border-radius: 8px;
  background: var(--fg); color: var(--bg);
  font: 0.85rem/1.3 system-ui, sans-serif; white-space: nowrap;
  visibility: hidden; opacity: 0; transition: opacity 0.12s; pointer-events: none; z-index: 20;
}
.hi.show .iast { visibility: visible; opacity: 1; }
@media (hover: hover) { .hi:hover .iast { visibility: visible; opacity: 1; } }
/* Global "अ/a" toggle: IAST always shown under the Devanagari. */
body.show-iast .hi { display: inline-flex; flex-direction: column; align-items: center; vertical-align: top; }
body.show-iast .hi .iast {
  position: static; transform: none; visibility: visible; opacity: 1; margin: 0; padding: 0;
  background: none; color: var(--muted); font-size: 0.7em;
}
.hi.big { font-size: 2.2rem; line-height: 1.4; }

/* Home */
.home-grid { display: grid; gap: 12px; margin-top: 12px; }
.tile-big { text-align: left; padding: 16px; display: grid; grid-template-columns: auto 1fr; column-gap: 14px; align-items: center; }
.tile-hi { grid-row: span 2; font-size: 1.8rem; min-width: 3.5em; text-align: center; }
.tile-title { font-weight: 600; font-size: 1.15rem; }
.tile-detail { color: var(--muted); font-size: 0.95rem; }
.home-stats { color: var(--muted); font-size: 0.9rem; margin-top: 16px; text-align: center; }

/* Home decks and "learn more" */
.deck { display: flex; flex-direction: column; gap: 6px; }
.deck .tile-big { width: 100%; }
.btn.more { align-self: stretch; min-height: 44px; padding: 8px 14px; font-size: 0.95rem; color: var(--accent); background: var(--accent-soft); border-color: transparent; text-align: center; }
.learn-more { margin: 16px 0; }
.topics { display: flex; flex-wrap: wrap; gap: 6px; justify-content: center; margin-top: 8px; }
.topics-label { width: 100%; color: var(--muted); font-size: 0.9rem; }
.btn.chip-btn { min-height: 40px; padding: 6px 12px; border-radius: 999px; font-size: 0.9rem; }
.segmented { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; }
.btn.seg.on { background: var(--accent); color: #fff; border-color: var(--accent); font-weight: 600; }

/* Flashcards */
.progress { color: var(--muted); font-size: 0.9rem; margin-bottom: 8px; }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: 18px;
  padding: 16px; min-height: 280px; display: flex; flex-direction: column; justify-content: center;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}
.card.tappable { cursor: pointer; }
.card-images { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; }
.card-img { max-width: 100%; max-height: 240px; border-radius: 10px; object-fit: contain; }
.card-images .card-img { flex: 1 1 45%; min-width: 120px; }
.card-images .card-img:only-child { flex-basis: 100%; }
.card-prompt { text-align: center; font-size: 2rem; font-weight: 600; padding: 24px 8px; }
.card.flipped .card-prompt { font-size: 1.3rem; padding: 4px; color: var(--muted); }
.card-hint { text-align: center; margin-top: 10px; font-size: 1.2rem; }
.tap-hint { text-align: center; color: var(--muted); font-size: 0.85rem; margin-top: 12px; }
.card-back { border-top: 1px solid var(--line); margin-top: 14px; padding-top: 14px; }
.card.flipped .card-img { max-height: 140px; }
.word-row { display: flex; align-items: center; justify-content: center; gap: 12px; }
.english { text-align: center; font-size: 1.3rem; margin-top: 6px; }
.meta { display: flex; gap: 6px; justify-content: center; margin-top: 8px; flex-wrap: wrap; }
.badge { font-family: system-ui, var(--deva-font); font-size: 0.8rem; padding: 2px 10px; border-radius: 999px; background: var(--line); }
.btn.audio { min-width: 48px; padding: 8px 12px; font-size: 1.2rem; }
.letter { font-family: var(--deva-font); font-size: 6rem; text-align: center; line-height: 1.3; }
.iast-big { font-size: 2rem; font-weight: 600; }
.matra, .note { text-align: center; color: var(--muted); margin-top: 6px; }
.script-back .example { text-align: center; margin-top: 10px; font-size: 1.15rem; }
.grades { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; margin-top: 14px; }
.btn.grade { padding: 8px 4px; text-align: center; }
.grade-name { font-weight: 600; font-size: 0.95rem; }
.grade-when { font-size: 0.75rem; color: var(--muted); }
.btn.grade-again { background: var(--g-again-bg); color: var(--g-again); border-color: var(--g-again); }
.btn.grade-hard { background: var(--g-hard-bg); color: var(--g-hard); border-color: var(--g-hard); }
.btn.grade-good { background: var(--g-good-bg); color: var(--g-good); border-color: var(--g-good); }
.btn.grade-easy { background: var(--g-easy-bg); color: var(--g-easy); border-color: var(--g-easy); }
.btn.grade .grade-when { color: inherit; opacity: 0.8; }
.btn.small { min-height: 40px; padding: 6px 14px; font-size: 0.95rem; }

/* Noun gender tones: the whole review screen, the card, chips and badges. */
.review { margin: 0 -16px; padding: 1px 16px 16px; border-radius: 0 0 18px 18px; }
.review.gender-m { background: var(--m-bg); }
.review.gender-f { background: var(--f-bg); }
.review.gender-m .card { background: var(--m-card); border-color: var(--m-fg); }
.review.gender-f .card { background: var(--f-card); border-color: var(--f-fg); }
.card-front { position: relative; }
.card-front > .badge { display: table; margin: 0 auto 8px; }
.badge.gender-m, .chip.gender-m { background: var(--m-bg); color: var(--m-fg); border-color: var(--m-fg); }
.badge.gender-f, .chip.gender-f { background: var(--f-bg); color: var(--f-fg); border-color: var(--f-fg); }
.done { text-align: center; margin-top: 32px; }
.done .btn { margin: 8px auto; }
.card-missing { text-align: center; font-size: 3rem; color: var(--muted); }

/* Script lesson */
.letters { display: flex; flex-direction: column; gap: 8px; margin: 12px 0; }
.letter-row { display: flex; align-items: center; gap: 12px; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 10px 12px; }
.letter-char { font-size: 2rem; min-width: 2.6em; text-align: center; }
.matra-inline { font-family: var(--deva-font); color: var(--muted); font-size: 1.2rem; margin-left: 6px; }
.letter-info { flex: 1; font-size: 0.95rem; }
.letter-info .note { text-align: left; margin: 0; }
.iast-small { font-weight: 600; }
.example .en { color: var(--muted); }

/* Grammar */
.explanation p { margin: 10px 0; }
.examples { display: flex; flex-direction: column; gap: 8px; }
.gexample { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 12px; }
.gex-hi { font-size: 1.3rem; }
.gloss { color: var(--muted); font-size: 0.85rem; font-style: italic; }
.gexample .en { font-size: 0.95rem; }
.vocab-strip { margin: 12px 0; }
.chip { display: inline-block; background: var(--card); border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px; margin: 0 6px 6px 0; font-size: 0.95rem; }
.ex-image { text-align: center; margin: 8px 0; }
.ex-prompt { text-align: center; margin: 24px 0 6px; font-size: 1.2rem; }
.ex-prompt .hi.big { font-size: 1.8rem; }
.ex-en { text-align: center; color: var(--muted); margin-bottom: 16px; }
.options { display: grid; gap: 8px; }
.btn.option { font-size: 1.4rem; }
.btn.option.selected { border-color: var(--accent); background: var(--accent-soft); }
.btn.option.right { border-color: var(--good); background: var(--good-soft); opacity: 1; }
.btn.option.wrong { border-color: var(--bad); background: var(--bad-soft); opacity: 1; }
.tile-answer, .tile-bank { display: flex; flex-wrap: wrap; gap: 8px; min-height: 64px; padding: 8px; border-radius: var(--radius); }
.tile-answer { border: 2px dashed var(--line); margin-bottom: 12px; }
.btn.tile { font-size: 1.35rem; padding: 8px 14px; }
.text-input { width: 100%; font: inherit; font-size: 1.2rem; padding: 12px; border-radius: var(--radius); border: 1px solid var(--line); background: var(--card); color: var(--fg); }
.text-input[lang="hi"] { font-family: var(--deva-font); }
.text-input.area { min-height: 120px; font-size: 0.9rem; font-family: ui-monospace, monospace; margin-bottom: 8px; }
.feedback { border-radius: var(--radius); padding: 12px; margin-top: 16px; font-size: 1.1rem; }
.feedback.good { background: var(--good-soft); color: var(--good); }
.feedback.bad { background: var(--bad-soft); color: var(--bad); }
.feedback .hi { color: var(--fg); }

/* Credits */
.credits { display: flex; flex-direction: column; gap: 10px; }
.credit { display: flex; gap: 12px; align-items: center; font-size: 0.85rem; }
.credit-thumb { width: 56px; height: 56px; object-fit: cover; border-radius: 8px; flex: none; display: flex; align-items: center; justify-content: center; background: var(--line); }
.credit-path { font-weight: 600; word-break: break-all; }