/* Sổ câu sai (review.html): cùng nền giấy điệp, mực tàu và bảng màu Đông Hồ với trang chủ */
:root {
  --bg: #F5E6C8;
  --bg-fiber: #E8D5B0;
  --paper-grain: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='paperNoise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='3' stitchTiles='stitch'/%3E%3CfeColorMatrix type='matrix' values='1 0 0 0 0  0 0.9 0 0 0  0 0 0.7 0 0  0 0 0 0.28 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23paperNoise)'/%3E%3C/svg%3E");
  --ink: #1A1A1A;
  --text: #2b2620;
  --muted: #6b5f4f;
  --paper: #FFFBF0;
  --line: #dcc79f;
  --ok: #2f7d4a;
  --ok-bg: #e4f2e2;
  --bad: #C83228;
  --bad-bg: #fbe3dc;
  --gold: #E6B422;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: 'Plus Jakarta Sans', 'Segoe UI', Tahoma, sans-serif;
  color: var(--text);
  background-color: var(--bg);
  background-image: var(--paper-grain), radial-gradient(ellipse at 50% 35%, transparent 45%, var(--bg-fiber) 100%);
  background-size: 180px 180px, 100% 100%;
  background-blend-mode: multiply, normal;
  min-height: 100vh;
  line-height: 1.55;
}

.rv-wrap {
  width: min(920px, calc(100% - 32px));
  margin: 0 auto;
  padding: 24px 0 48px;
}

.rv-head {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 18px;
}

.rv-head h1 {
  margin: 0;
  font-family: 'Fraunces', Georgia, serif;
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  color: var(--ink);
  letter-spacing: -0.01em;
}

.rv-home {
  flex-shrink: 0;
  padding: 6px 14px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  background: var(--paper);
  color: var(--ink);
  font-weight: 800;
  font-size: 0.85rem;
  text-decoration: none;
  box-shadow: 0 3px 0 var(--ink);
}

.rv-home:hover { transform: translateY(-1px); }

/* Thẻ chọn deck */
.rv-decks {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 16px;
}

.rv-tab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px 6px 14px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  background: var(--paper);
  color: var(--ink);
  font: inherit;
  font-weight: 700;
  font-size: 0.86rem;
  cursor: pointer;
}

.rv-tab.is-on {
  background: var(--deck);
  color: #FFF6E3;
}

.rv-badge {
  min-width: 24px;
  padding: 0 7px;
  border-radius: 999px;
  background: var(--bad);
  color: #fff;
  font-size: 0.76rem;
  line-height: 22px;
  text-align: center;
}

.rv-badge.is-zero { background: rgba(26, 26, 26, 0.14); color: inherit; }
.rv-tab.is-on .rv-badge { background: #FFF6E3; color: var(--ink); }

/* Tổng kết tiến độ của deck */
.rv-summary {
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  gap: 10px;
  margin-bottom: 16px;
}

.rv-stat {
  flex: 1 1 110px;
  padding: 10px 14px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--paper);
}

.rv-stat b {
  display: block;
  font-size: 1.45rem;
  line-height: 1.2;
  color: var(--ink);
}

.rv-stat span {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.rv-stat.is-open b { color: var(--bad); }
.rv-stat.is-fixed b { color: var(--ok); }

.rv-open {
  flex: 0 0 auto;
  align-self: center;
  padding: 7px 16px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  background: var(--deck);
  color: #FFF6E3;
  font-weight: 800;
  font-size: 0.86rem;
  text-decoration: none;
  box-shadow: 0 3px 0 var(--ink);
}

.rv-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}

.rv-seg {
  display: inline-flex;
  border: 2px solid var(--ink);
  border-radius: 999px;
  overflow: hidden;
  background: var(--paper);
}

.rv-seg button {
  padding: 6px 14px;
  border: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-weight: 700;
  font-size: 0.86rem;
  cursor: pointer;
}

.rv-seg button + button { border-left: 2px solid var(--ink); }
.rv-seg button[aria-pressed="true"] { background: var(--ink); color: #FFF6E3; }

.rv-clear, .rv-more {
  padding: 6px 14px;
  border: 2px dashed var(--muted);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-weight: 700;
  font-size: 0.84rem;
  cursor: pointer;
}

.rv-clear { margin-left: auto; }
.rv-more { display: block; margin: 18px auto 0; }

/* Thẻ câu hỏi */
.rv-list {
  display: grid;
  gap: 14px;
}

.rv-card {
  padding: 14px 18px 12px 20px;
  border: 2px solid var(--ink);
  border-left: 8px solid var(--deck);
  border-radius: 6px;
  background: var(--paper);
  box-shadow: 0 6px 14px rgba(96, 65, 18, 0.12);
}

.rv-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 10px;
  margin-bottom: 8px;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--muted);
}

.rv-deck { color: var(--deck); }

.rv-tag {
  padding: 1px 9px;
  border: 1.5px solid currentColor;
  border-radius: 999px;
}

.rv-miss { color: var(--bad); }
.rv-fixed { color: var(--ok); }

.rv-q {
  margin-bottom: 10px;
  font-size: 1.02rem;
  font-weight: 600;
  color: var(--ink);
  white-space: pre-line;
}

.rv-q u, .rv-otext u { text-decoration-thickness: 2px; text-underline-offset: 3px; }

.rv-ctx {
  margin-bottom: 10px;
  border: 1.5px dashed var(--line);
  border-radius: 6px;
  background: rgba(245, 230, 200, 0.35);
}

.rv-ctx summary {
  padding: 6px 12px;
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--muted);
  cursor: pointer;
}

.rv-ctx h3 {
  margin: 4px 14px 6px;
  font-size: 0.95rem;
  color: var(--ink);
}

.rv-ctx-text {
  max-height: 340px;
  overflow: auto;
  padding: 0 14px 12px;
  font-size: 0.92rem;
  white-space: pre-line;
}

.rv-opts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 8px;
  margin: 0 0 10px;
  padding: 0;
  list-style: none;
}

.rv-opt {
  display: flex;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px;
  width: 100%;
  height: 100%;
  padding: 8px 12px;
  border: 1.5px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: var(--text);
  font: inherit;
  font-size: 0.93rem;
  text-align: left;
  cursor: pointer;
}

.rv-opt:not(:disabled):hover { border-color: var(--ink); }
.rv-opt:disabled { cursor: default; }

.rv-letter {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  border: 1.5px solid currentColor;
  border-radius: 50%;
  font-size: 0.78rem;
  font-weight: 800;
  line-height: 21px;
  text-align: center;
}

.rv-otext { flex: 1; min-width: 0; padding-top: 1px; }

.rv-note {
  flex-basis: 100%;
  padding-left: 32px;
  font-size: 0.74rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.rv-opt.is-correct { border: 2px solid var(--ok); background: var(--ok-bg); color: #1d4d2e; }
.rv-opt.is-picked { border: 2px solid var(--bad); background: var(--bad-bg); color: #7c1d16; }
.rv-opt.is-dim { opacity: 0.55; }

.rv-gapans {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 8px;
  margin-bottom: 10px;
}

.rv-gapans .rv-note { padding-left: 0; }

.rv-gapform {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 10px;
}

.rv-input {
  flex: 1 1 200px;
  min-width: 0;
  padding: 8px 12px;
  border: 1.5px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: var(--text);
  font: inherit;
  font-size: 0.95rem;
}

.rv-input:focus { outline: 2px solid var(--ink); outline-offset: 1px; }

.rv-check {
  padding: 8px 18px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  background: var(--ink);
  color: #FFF6E3;
  font: inherit;
  font-weight: 800;
  font-size: 0.86rem;
  cursor: pointer;
}

.rv-link {
  color: var(--deck);
  font-size: 0.84rem;
  font-weight: 800;
  text-decoration: none;
}

.rv-link:hover { text-decoration: underline; }

.rv-why {
  margin-bottom: 8px;
  padding: 9px 13px;
  border-left: 4px solid var(--gold);
  border-radius: 4px;
  background: rgba(230, 180, 34, 0.12);
  font-size: 0.9rem;
  white-space: pre-line;
}

.rv-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.rv-result { font-size: 0.86rem; font-weight: 800; }
.rv-result.is-ok { color: var(--ok); }
.rv-result.is-bad { color: var(--bad); }

.rv-remove {
  margin-left: auto;
  padding: 3px 10px;
  border: 0;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.8rem;
  font-weight: 700;
  text-decoration: underline;
  cursor: pointer;
}

.rv-empty {
  padding: 36px 16px;
  text-align: center;
  color: var(--muted);
  font-weight: 700;
}

.rv-empty img { width: 110px; height: auto; }
.rv-empty p { margin: 8px 0 0; }

@media (max-width: 560px) {
  .rv-head { flex-direction: column; align-items: flex-start; gap: 10px; }
  .rv-clear { margin-left: 0; }
  .rv-card { padding: 12px 12px 10px 14px; }
}