/* PPL(A) Practice — bright, plain, phone-first. No build step, no network. */

:root {
  --ink: #10202c;
  --ink-soft: #4a5c6b;
  --line: #d7e2ea;
  --bg: #f7fbfe;
  --surface: #ffffff;
  --accent: #0b6bcb;
  --accent-dark: #08529d;
  --accent-wash: #eaf3fd;
  --good: #0d7a4f;
  --good-wash: #e8f7ef;
  --bad: #bd2c2c;
  --bad-wash: #fdecec;
  --radius: 12px;
  --max: 44rem;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 400 1.0625rem/1.55 ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  overflow-x: hidden;
}

h1, h2, p, fieldset, legend { margin: 0; }

h1 {
  font-size: clamp(1.5rem, 5.5vw, 2rem);
  line-height: 1.2;
  letter-spacing: -0.01em;
  overflow-wrap: break-word;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  padding: 0.6rem 1rem;
  background: var(--accent);
  color: #fff;
  z-index: 10;
}
.skip-link:focus { left: 0.5rem; top: 0.5rem; border-radius: 8px; }

.site-head, .site-foot, .wrap {
  width: 100%;
  max-width: var(--max);
  margin-inline: auto;
  padding-inline: 1.15rem;
}

.site-head { padding-top: 1.6rem; }

.brand {
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--accent);
}
.brand span { color: var(--ink); }

.tagline {
  font-size: 0.875rem;
  color: var(--ink-soft);
  margin-top: 0.15rem;
}

.wrap { padding-block: 1.6rem 3rem; }

.screen { max-width: 100%; }

.lede {
  color: var(--ink-soft);
  margin-top: 0.6rem;
  max-width: 38rem;
}

/* ---------- start form ---------- */

#start-form { margin-top: 1.75rem; display: grid; gap: 1.5rem; }

.field { border: 0; padding: 0; min-width: 0; }

legend {
  font-weight: 650;
  padding: 0;
  margin-bottom: 0.7rem;
}

.hint { font-weight: 400; color: var(--ink-soft); }

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  min-width: 0;
}

.chip {
  position: relative;
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  min-width: 0;
  max-width: 100%;
}

.chip span {
  display: block;
  padding: 0.5rem 0.95rem;
  font-size: 0.9375rem;
  line-height: 1.3;
  overflow-wrap: break-word;
  color: var(--ink-soft);
  cursor: pointer;
}

.chip input {
  position: absolute;
  inset: 0;
  margin: 0;
  opacity: 0;
  cursor: pointer;
}

.chip:has(input:checked) {
  background: var(--accent-wash);
  box-shadow: inset 0 0 0 1.5px var(--accent);
}
.chip:has(input:checked) span { color: var(--accent-dark); font-weight: 600; }

.chip:has(input:focus-visible) { outline: 3px solid var(--accent); outline-offset: 2px; }

.chips-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1rem;
  margin-top: 0.7rem;
}

.switch {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.9375rem;
  color: var(--ink-soft);
  cursor: pointer;
}
.switch input { width: 1.15rem; height: 1.15rem; accent-color: var(--accent); }

button { font: inherit; cursor: pointer; }

.primary {
  display: block;
  width: 100%;
  padding: 0.85rem 1.25rem;
  border: 0;
  border-radius: var(--radius);
  background: var(--accent);
  color: #fff;
  font-weight: 650;
  box-shadow: 0 1px 0 var(--accent-dark);
}
.primary:hover { background: var(--accent-dark); }

.link {
  background: none;
  border: 0;
  padding: 0.4rem 0.6rem;
  margin-inline: -0.6rem;
  border-radius: 8px;
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  font-size: 0.9375rem;
}

button:focus-visible, .chip input:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }

.error {
  color: var(--bad);
  background: var(--bad-wash);
  border-radius: var(--radius);
  padding: 0.7rem 0.9rem;
  font-size: 0.9375rem;
}

.chips-count .chip span {
  min-width: 3.4rem;
  text-align: center;
  padding-inline: 0.75rem;
}

/* ---------- quiz ---------- */

.bar { margin-top: 0.2rem; }
.bar-row {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--ink-soft);
  font-variant-numeric: tabular-nums;
}

.track {
  height: 6px;
  margin-top: 0.45rem;
  border-radius: 999px;
  background: var(--line);
  overflow: hidden;
}
.fill {
  height: 100%;
  width: 0;
  background: var(--accent);
  transition: width 0.2s ease;
}

.subject-tag {
  margin-top: 1.6rem;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}

.question {
  margin-top: 0.4rem;
  font-size: clamp(1.15rem, 4.6vw, 1.35rem);
  line-height: 1.35;
  overflow-wrap: break-word;
}

/* headings get focus only for screen-reader landing, so no ring */
.question:focus,
#res-h:focus,
#start-h:focus { outline: none; }

.options {
  display: grid;
  gap: 0.6rem;
  margin-top: 1.3rem;
}

.opt {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
  width: 100%;
  padding: 0.85rem 0.95rem;
  text-align: left;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--ink);
  line-height: 1.4;
  overflow-wrap: break-word;
  min-width: 0;
}
.opt:hover:not(:disabled) { border-color: var(--accent); background: var(--accent-wash); }
.opt:disabled { cursor: default; opacity: 1; }

.opt .letter {
  flex: 0 0 1.55rem;
  height: 1.55rem;
  border-radius: 50%;
  background: var(--bg);
  border: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 0.8125rem;
  font-weight: 700;
  display: grid;
  place-items: center;
}
.opt .text { min-width: 0; }

.opt[data-state="correct"] {
  border-color: var(--good);
  background: var(--good-wash);
}
.opt[data-state="correct"] .letter { background: var(--good); border-color: var(--good); color: #fff; }
.opt[data-state="wrong"] {
  border-color: var(--bad);
  background: var(--bad-wash);
}
.opt[data-state="wrong"] .letter { background: var(--bad); border-color: var(--bad); color: #fff; }
.opt[data-state="muted"] { color: var(--ink-soft); opacity: 0.6; }

.feedback { margin-top: 1.2rem; }

.verdict { font-weight: 700; }
.verdict.is-good { color: var(--good); }
.verdict.is-bad { color: var(--bad); }

.explain { margin-top: 0.35rem; color: var(--ink); }

.source {
  margin-top: 0.5rem;
  font-size: 0.8125rem;
  color: var(--ink-soft);
}

#next-btn { margin-top: 1.4rem; }

.quit { margin-top: 1rem; }

/* ---------- results ---------- */

.score-big {
  margin-top: 1rem;
  font-size: clamp(2.2rem, 9vw, 3rem);
  font-weight: 750;
  line-height: 1.1;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

.score-big[data-pass="yes"] { color: var(--good); }
.score-big[data-pass="no"] { color: var(--bad); }

.sub-h {
  margin-top: 2rem;
  font-size: 1.05rem;
  letter-spacing: 0.01em;
}

#review { display: grid; gap: 1.4rem; margin-top: 1rem; }

.review-item { border-top: 1px solid var(--line); padding-top: 1rem; }
.review-q { font-weight: 600; }
.review-row { margin-top: 0.45rem; font-size: 0.9375rem; }
.review-row .lbl { font-weight: 700; }
.review-row.is-bad .lbl { color: var(--bad); }
.review-row.is-good .lbl { color: var(--good); }
.review-exp { margin-top: 0.6rem; font-size: 0.9375rem; color: var(--ink-soft); }

#again-btn { margin-top: 1.5rem; }
#again-btn-2 { margin-top: 2.5rem; }

.site-foot {
  padding-bottom: 2rem;
  font-size: 0.8125rem;
  color: var(--ink-soft);
}

.site-foot .build-stamp {
  margin-top: 0.15rem;
  font-size: 0.75rem;
  letter-spacing: 0.01em;
  color: var(--ink-soft);
  font-variant-numeric: tabular-nums;
}

@media (min-width: 40rem) {
  .primary { width: auto; min-width: 14rem; }
  .site-head { padding-top: 2.2rem; }
}

@media (prefers-reduced-motion: reduce) {
  .fill { transition: none; }
  .card { transition: none; }
}

/* ---------- flashcards ---------- */

.cards-entry {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
}

.small { font-size: 0.9375rem; }

.cards-summary {
  margin-top: 0.75rem;
  font-size: 0.875rem;
  color: var(--ink-soft);
  font-variant-numeric: tabular-nums;
}

.secondary {
  display: block;
  width: 100%;
  margin-top: 0.9rem;
  padding: 0.85rem 1.25rem;
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--accent-dark);
  font-weight: 650;
}
.secondary:hover { background: var(--accent-wash); }

#reset-cards { margin-top: 0.6rem; }

.card-shell { margin-top: 1rem; }

.card {
  display: block;
  width: 100%;
  min-height: 15rem;
  padding: 1.1rem 1.15rem;
  text-align: left;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--ink);
  box-shadow: 0 1px 2px rgba(16, 32, 44, 0.06);
}

.card-side { display: block; }

.card-hint {
  display: block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.card-question {
  display: block;
  margin-top: 0.6rem;
  font-weight: 600;
}

.card-back { border-top: 0; }

.card-back .card-hint { color: var(--accent); }

.card-answer {
  display: block;
  margin-top: 0.55rem;
  font-weight: 650;
  color: var(--good);
  overflow-wrap: break-word;
}

.card-back .explain { display: block; margin-top: 0.7rem; font-size: 1rem; }
.card-back .source { display: block; }

.cards-status {
  min-height: 1.4rem;
  margin-top: 0.85rem;
  font-size: 0.875rem;
  color: var(--ink-soft);
}

.grade-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.6rem;
  margin-top: 0.4rem;
}

.again, .know {
  padding: 0.85rem 1rem;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--ink);
  font-weight: 650;
}
.again:disabled, .know:disabled { opacity: 0.5; cursor: default; }
.again:not(:disabled):hover { border-color: var(--bad); background: var(--bad-wash); }
.know:not(:disabled):hover { border-color: var(--good); background: var(--good-wash); }

.grade-key {
  display: inline-grid;
  place-items: center;
  min-width: 1.35rem;
  height: 1.35rem;
  margin-right: 0.3rem;
  border-radius: 6px;
  background: var(--bg);
  border: 1px solid var(--line);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--ink-soft);
}

.kbd-note { margin-top: 1.25rem; font-size: 0.8125rem; }
kbd {
  font: inherit;
  font-size: 0.75rem;
  padding: 0.05rem 0.3rem;
  border: 1px solid var(--line);
  border-bottom-width: 2px;
  border-radius: 5px;
  background: var(--surface);
}