:root {
  --ink: #1c1917;
  --paper: #faf7f2;
  --card: #fffef9;
  --line: #e7e0d4;
  --accent: #9a3412;
  --soft: #fff1e6;
  --ok: #14532d;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font: 17px/1.65 "Noto Sans Devanagari", "Nirmala UI", "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
}
header {
  padding: 1.4rem 1.25rem 1.15rem;
  border-bottom: 3px solid var(--accent);
  background: var(--card);
}
header .tag { margin: 0 0 .3rem; color: var(--accent); font-size: .88rem; }
header h1 { margin: 0 0 .35rem; font-size: 1.45rem; }
header .sub { margin: 0; max-width: 52rem; }
main { max-width: 820px; margin: 0 auto; padding: 1.1rem 1.1rem 5rem; }
.bar {
  position: sticky; top: 0; z-index: 6;
  display: flex; flex-wrap: wrap; gap: .5rem; align-items: center;
  justify-content: space-between;
  background: var(--card);
  border-bottom: 1px solid var(--line);
  padding: .55rem .9rem;
}
.timer {
  font-weight: 750;
  font-variant-numeric: tabular-nums;
  color: var(--accent);
  font-size: 1.15rem;
}
.timer.warn { color: #b45309; }
.timer.dead { color: #991b1b; }
.block {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1rem 1.15rem;
  margin: .85rem 0;
}
.tip { background: #ecfdf5; border-left: 4px solid #047857; padding: .7rem 1rem; margin: .85rem 0; border-radius: 0 10px 10px 0; }
.ex { background: #fff7ed; border: 1px dashed #fdba74; padding: .7rem 1rem; margin: .7rem 0; border-radius: 10px; }
.btn {
  cursor: pointer;
  border: 2px solid var(--accent);
  background: var(--accent);
  color: #fff;
  border-radius: 10px;
  padding: .45rem .9rem;
  font: inherit;
  font-weight: 650;
}
.btn.ghost { background: #fff; color: var(--accent); }
.btn:disabled { opacity: .45; cursor: default; }
.qa {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: .9rem 1rem;
  margin: .75rem 0;
  background: #fff;
}
.qa.flagged { outline: 2px solid #d97706; }
.qa .meta { font-size: .82rem; color: #78716c; margin: 0 0 .35rem; }
.pill { display: inline-block; font-size: .72rem; font-weight: 700; padding: .12rem .45rem; border-radius: 999px; margin-right: .3rem; }
.e { background: #dcfce7; color: #14532d; }
.m { background: #fef3c7; color: #92400e; }
.h { background: #fee2e2; color: #991b1b; }
.opts { list-style: none; padding: 0; margin: .45rem 0; }
.opt {
  display: block;
  cursor: pointer;
  margin: .3rem 0;
  padding: .5rem .7rem;
  background: var(--paper);
  border-radius: 8px;
  border: 2px solid #e7e0d4;
}
.opt:hover { border-color: var(--accent); }
.opt input { margin-right: .45rem; }
.hintbox {
  display: none;
  margin-top: .5rem;
  padding: .55rem .7rem;
  background: #eff6ff;
  border-radius: 8px;
  border: 1px solid #bfdbfe;
}
.hintbox.on { display: block; }
.row { display: flex; flex-wrap: wrap; gap: .4rem; margin-top: .45rem; }
.sol {
  margin-top: .55rem;
  padding: .65rem .75rem;
  background: #f0fdf4;
  border-radius: 8px;
  border: 1px solid #bbf7d0;
}
.qa.wrong .sol { background: #fef2f2; border-color: #fecaca; }
.qa.ok-row { border-color: #86efac; }
.qa.bad-row { border-color: #fca5a5; }
table { width: 100%; border-collapse: collapse; font-size: .95rem; margin: .6rem 0; }
th, td { border: 1px solid var(--line); padding: .4rem .5rem; text-align: left; }
th { background: var(--soft); }
.score { font-size: 1.6rem; font-weight: 750; color: var(--accent); margin: .3rem 0; }
footer { text-align: center; color: #78716c; font-size: .85rem; padding: 1.2rem; }
a.back { color: var(--accent); }