:root {
  --ink: #172b3a;
  --muted: #71818b;
  --cream: #fffaf1;
  --orange: #f2764b;
  --blue: #75b8d8;
  --green: #82b79c;
  --line: #e8e1d6;
  --white: #fff;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--cream);
  color: var(--ink);
  font-family: 'DM Sans', 'Noto Sans SC', sans-serif;
}
a { color: inherit; text-decoration: none; }

.topbar {
  height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1000px;
  margin: auto;
  padding: 0 28px;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 11px;
  background: var(--orange);
  color: #fff;
  font-size: 21px;
  font-weight: 800;
  transform: rotate(-5deg);
}
.brand strong, .brand small { display: block; }
.brand strong { font-size: 15px; }
.brand small { font-size: 10px; color: var(--muted); letter-spacing: 1.1px; margin-top: 2px; }
.paper-tag {
  border: 1px solid var(--line);
  background: transparent;
  border-radius: 22px;
  padding: 10px 15px;
  color: var(--ink);
  font-weight: 700;
  font-size: 13px;
}

main { max-width: 1000px; margin: auto; padding: 0 28px; }

.banner { padding: 56px 0 30px; }
.eyebrow {
  text-transform: uppercase;
  color: var(--orange);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 2px;
  margin: 0 0 14px;
}
.banner h1 { font-size: 40px; line-height: 1.2; letter-spacing: -1px; margin: 0 0 12px; }
.intro { color: var(--muted); font-size: 14px; margin: 0; }

.practice-layout {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 22px;
  align-items: start;
}

.quiz-card {
  background: #fff;
  border-radius: 14px;
  box-shadow: 0 12px 35px #44505c0d;
  overflow: hidden;
}
.quiz-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
  border-bottom: 1px solid #f0ede8;
  font-size: 11px;
  color: var(--muted);
}
.quiz-top span:first-child { color: var(--orange); font-weight: 700; font-size: 12px; }

.live-stats {
  display: flex;
  align-items: center;
  gap: 22px;
  padding: 12px 24px;
  border-bottom: 1px solid #f0ede8;
  font-size: 12px;
  color: var(--muted);
}
.live-stats strong { font-size: 15px; color: var(--ink); margin-left: 4px; }
.stat-correct strong { color: #43875e; }
.stat-wrong strong { color: #d0604c; }
.stat-rate strong { color: var(--orange); }
.q-badge {
  margin-left: auto;
  font-size: 11px;
  color: #b45309;
  background: #fff4e0;
  border: 1px solid #f6d8a8;
  border-radius: 20px;
  padding: 4px 10px;
  font-weight: 700;
}

.quiz-body { padding: 26px 24px; }
.question-image {
  display: block;
  max-width: 100%;
  max-height: 380px;
  margin: 0 auto 18px;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px;
  background: #fff;
}
.question-text {
  font-family: 'Noto Sans SC', sans-serif;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.7;
  margin: 0 0 16px;
  white-space: pre-line;
}
.options { display: grid; grid-template-columns: 1fr 1fr; gap: 9px; }
.options.letter-options { grid-template-columns: repeat(5, 1fr); }
.option {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  text-align: left;
  padding: 13px 15px;
  cursor: pointer;
  font: inherit;
  font-size: 14px;
  color: var(--ink);
  line-height: 1.5;
}
.options.letter-options .option { text-align: center; font-weight: 800; }
.option:hover { border-color: var(--orange); background: #fffaf5; }
.option.correct { border-color: #6fb28a; background: #edfaef; color: #3a8056; }
.option.wrong { border-color: #e58a76; background: #fff1ed; }
.feedback { font-size: 13px; min-height: 20px; margin-top: 14px; }
.feedback.good { color: #43875e; }
.feedback.bad { color: #d0604c; }

.quiz-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
  border-top: 1px solid #f0ede8;
}
.progress-track {
  flex: 1;
  height: 6px;
  border-radius: 6px;
  background: #edf0ea;
  margin-right: 18px;
}
.progress-track i {
  display: block;
  height: 100%;
  width: 0;
  background: var(--orange);
  border-radius: 6px;
  transition: width .3s;
}
.button {
  border: 0;
  cursor: pointer;
  font: inherit;
  font-weight: 700;
  border-radius: 8px;
  padding: 12px 16px;
  display: inline-flex;
  gap: 14px;
  align-items: center;
}
.button span { font-size: 16px; }
.dark { background: var(--ink); color: #fff; font-size: 13px; }
#prevButton { margin-right: 8px; background: #fff; color: var(--ink); border: 1px solid var(--line); }
.primary { background: var(--ink); color: #fff; box-shadow: 0 7px 18px #172b3a20; }

.side-note {
  background: #f7e7d8;
  border-radius: 14px;
  padding: 28px 26px;
  position: sticky;
  top: 20px;
}
.note-star { color: var(--orange); font-size: 28px; }
.side-note h3 { margin: 20px 0 12px; font-size: 17px; }
.side-note p { font-size: 13px; line-height: 1.9; color: #806f64; }
.note-line { height: 1px; background: #d9bd9f; margin-top: 30px; }
.note-caption { display: block; color: #c38a67; font-size: 10px; letter-spacing: 2px; margin-top: 12px; }

.modal-overlay {
  position: fixed;
  inset: 0;
  background: #172b3a66;
  display: grid;
  place-items: center;
  padding: 20px;
  z-index: 50;
  backdrop-filter: blur(3px);
}
.result-card {
  background: #fff;
  border-radius: 16px;
  padding: 34px 30px;
  box-shadow: 0 24px 60px #172b3a40;
  text-align: center;
  width: min(100%, 560px);
  max-height: 88vh;
  overflow: auto;
  position: relative;
}
.modal-close {
  position: absolute;
  top: 14px;
  right: 16px;
  border: 0;
  background: transparent;
  font-size: 26px;
  color: var(--muted);
  cursor: pointer;
  line-height: 1;
}
.modal-close:hover { color: var(--orange); }
.result-card h2 { font-size: 26px; margin: 0 0 18px; }
.result-stats { display: flex; justify-content: center; gap: 14px; margin-bottom: 20px; }
.rs { flex: 1; max-width: 130px; background: #faf7f1; border-radius: 12px; padding: 14px 10px; }
.rs strong { display: block; font-size: 26px; }
.rs span { font-size: 12px; color: var(--muted); }
.rs.correct strong { color: #43875e; }
.rs.wrong strong { color: #d0604c; }
.rs.rate strong { color: var(--orange); }
.result-sub {
  font-size: 13px;
  color: var(--muted);
  text-align: left;
  margin: 22px 0 12px;
  font-weight: 700;
}
.result-list { text-align: left; }
.wrong-item { border: 1px solid var(--line); border-radius: 9px; padding: 13px 16px; margin-bottom: 9px; }
.wrong-no {
  display: inline-block;
  font-size: 11px;
  color: #fff;
  background: var(--orange);
  border-radius: 20px;
  padding: 4px 10px;
  margin-bottom: 8px;
}
.wrong-item p { font-size: 13px; line-height: 1.6; margin: 0 0 4px; }
.wrong-answer { color: #3a8056; font-weight: 700; }

footer {
  border-top: 1px solid var(--line);
  max-width: 1000px;
  margin: auto;
  padding: 25px 28px;
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  color: var(--muted);
}
footer span:first-child { color: var(--ink); font-weight: 700; }

@media (max-width: 760px) {
  .topbar { height: 66px; padding: 0 18px; }
  main { padding: 0 18px; }
  .banner { padding: 38px 0 24px; }
  .banner h1 { font-size: 30px; }
  .practice-layout { grid-template-columns: 1fr; }
  .side-note { display: none; }
  .quiz-body { padding: 20px 16px; }
  .options { grid-template-columns: 1fr; }
  .options.letter-options { grid-template-columns: repeat(5, 1fr); }
  .quiz-bottom { gap: 12px; }
  .result-card { padding: 28px 18px; }
  footer { padding: 22px 18px; gap: 15px; flex-direction: column; }
}