/* ============================================
   JAPANESE QUIZ — SHARED STYLES
   Dùng chung cho tất cả bài quiz N5 → N1
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+JP:wght@300;400;600;700&family=Noto+Sans+JP:wght@300;400;500&family=Shippori+Mincho:wght@400;600;800&display=swap');

:root {
  --ink: #1a1208;
  --paper: #faf6ef;
  --paper2: #f3ede2;
  --red: #c0392b;
  --red-light: #e74c3c;
  --gold: #c9960c;
  --green: #1a6b3c;
  --green-light: #27ae60;
  --border: #d4c5a9;
  --shadow: rgba(26,18,8,0.12);
  --muted: #7a6a52;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: 'Noto Sans JP', sans-serif;
  background: var(--paper);
  color: var(--ink);
  min-height: 100vh;
  background-image:
    radial-gradient(ellipse at 20% 0%, rgba(201,150,12,0.07) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 100%, rgba(192,57,43,0.05) 0%, transparent 50%);
}

/* ── HEADER ── */
header {
  text-align: center;
  padding: 2.5rem 1rem 1.5rem;
  border-bottom: 2px solid var(--border);
  position: relative;
  overflow: hidden;
}
header::before {
  content: attr(data-bg-char);
  position: absolute;
  font-family: 'Shippori Mincho', serif;
  font-size: 18rem;
  color: rgba(192,57,43,0.04);
  top: -4rem;
  left: 50%;
  transform: translateX(-50%);
  pointer-events: none;
  line-height: 1;
}
.header-badge {
  display: inline-block;
  background: var(--red);
  color: white;
  font-family: 'Noto Serif JP', serif;
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  padding: 0.25rem 0.8rem;
  border-radius: 2px;
  margin-bottom: 0.8rem;
}
header h1 {
  font-family: 'Shippori Mincho', serif;
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.02em;
  line-height: 1.1;
}
header h1 span { color: var(--red); }
header p.sub {
  font-family: 'Noto Sans JP', sans-serif;
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 0.5rem;
  letter-spacing: 0.05em;
}

/* ── BACK LINK ── */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  color: var(--muted);
  text-decoration: none;
  font-size: 0.8rem;
  padding: 0.8rem 1.5rem 0;
  max-width: 720px;
  margin: 0 auto;
  transition: color 0.2s;
}
.back-link:hover { color: var(--red); }
.back-link svg { width: 14px; height: 14px; }

/* ── PROGRESS ── */
.progress-wrap {
  max-width: 720px;
  margin: 1rem auto 0;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}
.progress-bar-bg {
  flex: 1;
  height: 6px;
  background: var(--border);
  border-radius: 999px;
  overflow: hidden;
}
.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--red), var(--gold));
  border-radius: 999px;
  transition: width 0.6s cubic-bezier(.4,0,.2,1);
}
.progress-text {
  font-size: 0.8rem;
  color: var(--muted);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}
.score-badge {
  background: var(--paper2);
  border: 1px solid var(--border);
  border-radius: 99px;
  padding: 0.2rem 0.8rem;
  font-size: 0.78rem;
  color: var(--ink);
  font-weight: 500;
}

/* ── MAIN CARD ── */
main {
  max-width: 720px;
  margin: 0 auto;
  padding: 1.5rem 1.5rem 4rem;
}
.quiz-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: 4px;
  box-shadow: 0 4px 32px var(--shadow);
  overflow: hidden;
  animation: slideUp 0.4s cubic-bezier(.4,0,.2,1);
}

/* ── ANIMATIONS ── */
@keyframes slideUp {
  from { opacity:0; transform: translateY(16px); }
  to   { opacity:1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity:0; transform:translateY(6px); }
  to   { opacity:1; transform:none; }
}
@keyframes popIn {
  from { opacity:0; transform: scale(0.9); }
  to   { opacity:1; transform: scale(1); }
}

/* ── QUESTION HEADER ── */
.q-header {
  background: var(--paper2);
  border-bottom: 1px solid var(--border);
  padding: 1.5rem 1.8rem 1.3rem;
  display: flex;
  gap: 1.2rem;
  align-items: flex-start;
}
.q-num {
  flex-shrink: 0;
  font-family: 'Shippori Mincho', serif;
  font-size: 0.7rem;
  color: var(--red);
  letter-spacing: 0.1em;
  background: rgba(192,57,43,0.08);
  border: 1px solid rgba(192,57,43,0.2);
  border-radius: 2px;
  padding: 0.15rem 0.5rem;
  margin-top: 0.3rem;
}
.q-body { flex: 1; }
.q-tag {
  font-size: 0.68rem;
  color: var(--muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.6rem;
  display: block;
}
.q-text {
  font-family: 'Noto Serif JP', serif;
  font-size: clamp(1.1rem, 2.5vw, 1.4rem);
  font-weight: 600;
  line-height: 1.7;
  color: var(--ink);
}

/* ── VOCAB STRIP ── */
.vocab-strip {
  padding: 0.6rem 1.8rem;
  background: rgba(201,150,12,0.06);
  border-bottom: 1px solid rgba(201,150,12,0.2);
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  align-items: center;
}
.vocab-label {
  font-size: 0.68rem;
  color: var(--gold);
  letter-spacing: 0.1em;
  font-weight: 500;
  margin-right: 0.2rem;
}
.vocab-chip {
  font-family: 'Noto Serif JP', serif;
  font-size: 0.82rem;
  background: white;
  border: 1px solid rgba(201,150,12,0.35);
  border-radius: 3px;
  padding: 0.15rem 0.6rem;
  cursor: pointer;
  transition: all 0.2s;
  color: var(--ink);
}
.vocab-chip:hover {
  background: var(--gold);
  color: white;
  border-color: var(--gold);
}

/* ── VOCAB POPUP ── */
.vocab-popup {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 100;
  align-items: center;
  justify-content: center;
  background: rgba(26,18,8,0.45);
  backdrop-filter: blur(3px);
}
.vocab-popup.open { display: flex; }
.vocab-popup-box {
  background: white;
  border: 1px solid var(--border);
  border-radius: 4px;
  box-shadow: 0 20px 60px rgba(26,18,8,0.25);
  max-width: 380px;
  width: 90%;
  overflow: hidden;
  animation: popIn 0.25s cubic-bezier(.4,0,.2,1);
}
.vp-top {
  background: var(--ink);
  color: white;
  padding: 1.2rem 1.5rem;
  display: flex;
  align-items: baseline;
  gap: 1rem;
  justify-content: space-between;
}
.vp-word {
  font-family: 'Shippori Mincho', serif;
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: 0.02em;
}
.vp-reading {
  font-size: 0.9rem;
  color: var(--gold);
  font-family: 'Noto Serif JP', serif;
}
.vp-close {
  background: none;
  border: none;
  color: rgba(255,255,255,0.5);
  font-size: 1.4rem;
  cursor: pointer;
  line-height: 1;
  padding: 0.2rem;
  transition: color 0.2s;
}
.vp-close:hover { color: white; }
.vp-body { padding: 1.2rem 1.5rem; }
.vp-type {
  font-size: 0.68rem;
  color: var(--red);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  font-weight: 600;
  margin-bottom: 0.5rem;
}
.vp-meaning {
  font-size: 1rem;
  color: var(--ink);
  font-weight: 500;
  margin-bottom: 0.8rem;
  line-height: 1.5;
}
.vp-example {
  background: var(--paper2);
  border-left: 3px solid var(--red);
  padding: 0.6rem 0.8rem;
  border-radius: 0 3px 3px 0;
  font-family: 'Noto Serif JP', serif;
  font-size: 0.88rem;
  color: var(--muted);
  line-height: 1.8;
}
.vp-example em {
  display: block;
  font-style: normal;
  font-size: 0.78rem;
  color: #aaa;
  margin-top: 0.3rem;
}

/* ── CHOICES ── */
.choices {
  padding: 1.4rem 1.8rem 1.2rem;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.7rem;
}
@media (max-width: 600px) {
  .choices { grid-template-columns: 1fr; }
}
.choice-btn {
  background: white;
  border: 1.5px solid var(--border);
  border-radius: 3px;
  padding: 0.85rem 1rem;
  cursor: pointer;
  text-align: left;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: 'Noto Serif JP', serif;
  font-size: 1rem;
  color: var(--ink);
  line-height: 1.4;
}
.choice-btn:hover:not(:disabled) {
  border-color: var(--ink);
  background: var(--paper2);
  transform: translateY(-1px);
  box-shadow: 0 3px 10px var(--shadow);
}
.choice-letter {
  flex-shrink: 0;
  width: 1.6rem;
  height: 1.6rem;
  border-radius: 50%;
  border: 1.5px solid currentColor;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.72rem;
  font-family: 'Noto Sans JP', sans-serif;
  font-weight: 600;
  color: var(--muted);
  transition: all 0.2s;
}
.choice-btn:hover:not(:disabled) .choice-letter { color: var(--ink); }
.choice-btn.correct {
  border-color: var(--green);
  background: rgba(26,107,60,0.06);
  color: var(--green);
}
.choice-btn.correct .choice-letter {
  background: var(--green);
  border-color: var(--green);
  color: white;
}
.choice-btn.wrong {
  border-color: var(--red);
  background: rgba(192,57,43,0.06);
  color: var(--red);
}
.choice-btn.wrong .choice-letter {
  background: var(--red);
  border-color: var(--red);
  color: white;
}
.choice-btn:disabled { cursor: default; }

/* ── EXPLANATION ── */
.explanation {
  display: none;
  margin: 0 1.8rem 1.4rem;
  border: 1px solid var(--border);
  border-radius: 3px;
  overflow: hidden;
}
.explanation.show { display: block; animation: fadeIn 0.35s ease; }
.exp-head {
  background: var(--paper2);
  padding: 0.6rem 1rem;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--muted);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.exp-head::before {
  content: '解説';
  font-family: 'Noto Serif JP', serif;
  font-weight: 600;
  color: var(--gold);
  font-size: 0.85rem;
  letter-spacing: 0.05em;
}
.exp-body {
  padding: 0.9rem 1rem;
  font-size: 0.9rem;
  line-height: 1.9;
  color: var(--ink);
}
.exp-body strong { color: var(--red); }
.exp-body .tip {
  margin-top: 0.7rem;
  padding: 0.5rem 0.8rem;
  background: rgba(201,150,12,0.08);
  border-left: 2px solid var(--gold);
  font-size: 0.82rem;
  color: var(--muted);
  border-radius: 0 2px 2px 0;
}

/* ── FOOTER ACTIONS ── */
.card-footer {
  padding: 1rem 1.8rem 1.4rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--border);
  flex-wrap: wrap;
  gap: 0.6rem;
}
.exp-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 0.45rem 0.9rem;
  font-size: 0.8rem;
  color: var(--muted);
  cursor: pointer;
  font-family: 'Noto Sans JP', sans-serif;
  transition: all 0.2s;
  display: none;
}
.exp-toggle.show { display: inline-flex; align-items: center; gap: 0.4rem; }
.exp-toggle:hover { border-color: var(--gold); color: var(--gold); }

.next-btn {
  background: var(--ink);
  color: white;
  border: none;
  border-radius: 3px;
  padding: 0.55rem 1.4rem;
  font-size: 0.88rem;
  font-family: 'Noto Sans JP', sans-serif;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  display: none;
  align-items: center;
  gap: 0.5rem;
  letter-spacing: 0.03em;
}
.next-btn.show { display: inline-flex; }
.next-btn:hover { background: var(--red); }
.next-btn svg { width: 14px; height: 14px; }

/* ── RESULT SCREEN ── */
.result-screen {
  display: none;
  text-align: center;
  padding: 3rem 1.5rem;
  animation: slideUp 0.5s cubic-bezier(.4,0,.2,1);
}
.result-screen.show { display: block; }
.result-kanji {
  font-family: 'Shippori Mincho', serif;
  font-size: 5rem;
  font-weight: 800;
  color: var(--red);
  line-height: 1;
  margin-bottom: 0.5rem;
}
.result-title {
  font-family: 'Noto Serif JP', serif;
  font-size: 1.4rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}
.result-sub {
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}
.result-score-big {
  font-family: 'Shippori Mincho', serif;
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--ink);
  line-height: 1;
}
.result-score-big span { color: var(--red); }
.result-label {
  font-size: 0.8rem;
  color: var(--muted);
  margin-bottom: 2rem;
  letter-spacing: 0.1em;
}
.restart-btn {
  background: var(--red);
  color: white;
  border: none;
  border-radius: 3px;
  padding: 0.7rem 2rem;
  font-size: 0.95rem;
  font-family: 'Noto Sans JP', sans-serif;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  letter-spacing: 0.05em;
}
.restart-btn:hover {
  background: #a93226;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(192,57,43,0.3);
}

/* ── VOCAB BLANK ── */
.blank {
  display: inline-block;
  border-bottom: 2px solid var(--red);
  min-width: 64px;
  text-align: center;
  color: var(--red);
  font-weight: 700;
  vertical-align: bottom;
}

/* ── MOBILE RESPONSIVE ── */
@media (max-width: 900px) {
  main { padding: 0.8rem 0.4rem 3rem; }
  .back-link { padding: 0.6rem 0.6rem 0; }
  .progress-wrap { padding: 0 0.6rem; }
  .q-header { padding: 0.9rem 0.9rem 0.8rem; gap: 0.4rem; flex-direction: column; }
  .vocab-strip { padding: 0.5rem 0.9rem; }
  .choices { padding: 0.9rem 0.9rem 0.7rem; }
  .card-footer { padding: 0.7rem 0.9rem 1rem; }
  .explanation { margin: 0 0.9rem 0; }
}

/* ── TOAST ── */
.toast {
  position: fixed;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: var(--ink);
  color: white;
  border-radius: 99px;
  padding: 0.6rem 1.4rem;
  font-size: 0.85rem;
  font-family: 'Noto Sans JP', sans-serif;
  transition: transform 0.35s cubic-bezier(.4,0,.2,1);
  z-index: 200;
  white-space: nowrap;
}
.toast.show { transform: translateX(-50%) translateY(0); }
.toast.ok { background: var(--green); }
.toast.ng { background: var(--red); }