:root {
  --ink: #16202f;
  --muted: #5d6878;
  --line: #d9e0e9;
  --paper: #ffffff;
  --surface: #f4f7f9;
  --teal: #0f766e;
  --teal-dark: #0b514d;
  --teal-soft: #e8f5f2;
  --amber-soft: #fdf6e3;
  --amber-line: #e0c887;
  --mono: "JetBrains Mono", Consolas, monospace;
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--surface); color: var(--ink);
  font-family: var(--sans); line-height: 1.6;
}
a { color: var(--teal); }
.skip-link {
  position: fixed; z-index: 100; top: 10px; left: 10px; padding: 10px 14px;
  color: #fff; background: var(--ink); border-radius: 7px; transform: translateY(-150%);
}
.skip-link:focus { transform: translateY(0); }

.topbar {
  display: flex; flex-wrap: wrap; gap: 14px; align-items: center;
  padding: 14px 22px; background: var(--paper); border-bottom: 1px solid var(--line);
}
.topbar .brand { display: flex; gap: 11px; align-items: center; text-decoration: none; color: inherit; }
.brand-mark {
  width: 38px; height: 38px; border-radius: 10px; background: var(--teal); color: #fff;
  display: grid; place-items: center; font-weight: 800;
}
.topbar strong { display: block; font-size: .95rem; }
.topbar small { color: var(--muted); font-size: .78rem; }
.topbar nav { margin-left: auto; display: flex; flex-wrap: wrap; gap: 16px; }
.topbar nav a { text-decoration: none; color: var(--muted); font-weight: 600; font-size: .88rem; }
.topbar nav a:hover { color: var(--teal); }

.sheet {
  max-width: 900px; margin: 26px auto 60px; background: var(--paper);
  border: 1px solid var(--line); border-radius: 12px; padding: 40px 46px;
}
.exam-head { text-align: center; border-bottom: 2px solid var(--ink); padding-bottom: 18px; }
.exam-head .univ { font-size: 1.28rem; font-weight: 800; letter-spacing: .01em; margin: 0; }
.exam-head .dept { color: var(--muted); font-size: .9rem; margin: 5px 0 14px; }
.exam-head .paper-title { font-size: 1.05rem; font-weight: 700; margin: 0; }
.exam-head .subject { margin: 6px 0 0; font-size: .97rem; }
.exam-meta {
  display: flex; flex-wrap: wrap; gap: 10px 30px; justify-content: space-between;
  margin: 16px 0 0; font-size: .9rem; font-weight: 600;
}
.exam-meta span { color: var(--muted); font-weight: 500; }
.exam-meta b { color: var(--ink); }

.instructions {
  margin: 24px 0 30px; padding: 16px 20px; background: var(--teal-soft);
  border-left: 4px solid var(--teal); border-radius: 0 8px 8px 0;
}
.instructions h2 { margin: 0 0 8px; font-size: .8rem; letter-spacing: .12em; text-transform: uppercase; color: var(--teal-dark); }
.instructions ol { margin: 0; padding-left: 20px; font-size: .92rem; }
.instructions li + li { margin-top: 5px; }

.part-head {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: 10px;
  margin: 34px 0 6px; padding-bottom: 8px; border-bottom: 1px solid var(--line);
}
.part-head h2 { margin: 0; font-size: 1.02rem; letter-spacing: .04em; text-transform: uppercase; }
.part-head .part-marks { margin-left: auto; font-size: .88rem; font-weight: 700; color: var(--teal-dark); }
.part-note { margin: 0 0 18px; font-size: .87rem; color: var(--muted); font-style: italic; }

.q { display: grid; grid-template-columns: 34px 1fr 58px; gap: 4px 12px; padding: 16px 0; border-bottom: 1px dashed var(--line); }
.q:last-child { border-bottom: 0; }
.q .qno { font-weight: 700; }
.q .qmarks { text-align: right; font-weight: 700; color: var(--teal-dark); white-space: nowrap; }
.q .qbody { min-width: 0; }
.q .qbody > :first-child { margin-top: 0; }
.q .qbody > :last-child { margin-bottom: 0; }
.q p { margin: 0 0 10px; }
.q ol, .q ul { margin: 8px 0 10px; padding-left: 22px; }
.q li + li { margin-top: 4px; }

.tags { grid-column: 2 / -1; display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; }
.tag {
  font-size: .7rem; font-weight: 700; letter-spacing: .04em; text-transform: uppercase;
  padding: 3px 8px; border-radius: 999px; background: var(--surface);
  border: 1px solid var(--line); color: var(--muted);
}
.tag-co { background: var(--teal-soft); border-color: #b9ded6; color: var(--teal-dark); }

.orbar {
  grid-column: 2 / -1; display: flex; align-items: center; gap: 12px;
  margin: 14px 0 4px; color: var(--muted); font-weight: 700; font-size: .8rem; letter-spacing: .12em;
}
.orbar::before, .orbar::after { content: ""; flex: 1; height: 1px; background: var(--line); }

pre {
  background: #10202b; color: #e6f1f5; border-radius: 9px; padding: 14px 16px;
  overflow-x: auto; font-family: var(--mono); font-size: .84rem; line-height: 1.5; margin: 10px 0;
}
code { font-family: var(--mono); font-size: .88em; background: var(--teal-soft); padding: 1px 5px; border-radius: 4px; }
pre code { background: none; padding: 0; color: inherit; font-size: 1em; }

.table-wrap { overflow-x: auto; margin: 18px 0; }
table { border-collapse: collapse; width: 100%; font-size: .89rem; }
th, td { border: 1px solid var(--line); padding: 8px 11px; text-align: left; vertical-align: top; }
th { background: var(--surface); font-weight: 700; }
td.num, th.num { text-align: center; white-space: nowrap; }
tfoot td { font-weight: 700; background: var(--teal-soft); }

.section-title { margin: 40px 0 4px; font-size: 1.05rem; }
.section-sub { margin: 0 0 16px; color: var(--muted); font-size: .9rem; }

.answer { border-left: 3px solid var(--teal); padding-left: 18px; margin: 0 0 6px; }
.scheme {
  margin: 12px 0 0; padding: 12px 16px; background: var(--amber-soft);
  border: 1px solid var(--amber-line); border-radius: 8px; font-size: .87rem;
}
.scheme b { display: block; font-size: .72rem; letter-spacing: .1em; text-transform: uppercase; color: #8a6d1f; margin-bottom: 6px; }
.scheme ul { margin: 0; padding-left: 20px; }
.scheme li + li { margin-top: 3px; }

.cards { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); margin: 22px 0 0; }
.card {
  display: block; padding: 18px 20px; background: var(--paper); border: 1px solid var(--line);
  border-radius: 11px; text-decoration: none; color: inherit;
}
.card:hover { border-color: var(--teal); }
.card h3 { margin: 0 0 5px; font-size: 1rem; }
.card p { margin: 0; color: var(--muted); font-size: .88rem; }
.card .chip { display: inline-block; margin-top: 10px; font-size: .74rem; font-weight: 700; color: var(--teal-dark); }

.footnote { margin: 34px 0 0; padding-top: 18px; border-top: 1px solid var(--line); color: var(--muted); font-size: .84rem; }
.endline { text-align: center; letter-spacing: .3em; color: var(--muted); font-size: .8rem; margin: 30px 0 0; }

@media (max-width: 640px) {
  .sheet { padding: 26px 20px; margin: 14px; border-radius: 10px; }
  .q { grid-template-columns: 26px 1fr; }
  .q .qmarks { grid-column: 2; text-align: left; margin-top: -6px; }
  .tags, .orbar { grid-column: 1 / -1; }
}

@media print {
  body { background: #fff; }
  .topbar, .skip-link, .no-print { display: none !important; }
  .sheet { max-width: none; margin: 0; border: 0; border-radius: 0; padding: 0; }
  .q { break-inside: avoid; }
  .instructions { background: none; border-left: 2px solid #000; }
  pre { background: #f4f4f4; color: #000; border: 1px solid #bbb; }
  a { color: #000; text-decoration: none; }
}

.q.no-rule { border-bottom: 0; padding-bottom: 4px; }
.q + .orbar { margin: 0 0 4px; }
.sample-ribbon {
  display: inline-block; margin-bottom: 12px; padding: 5px 14px; border-radius: 999px;
  background: var(--amber-soft); border: 1px solid var(--amber-line);
  font-size: .74rem; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; color: #8a6d1f;
}
.blank { display: inline-block; min-width: 130px; border-bottom: 1px solid var(--muted); }