:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --ink: #1f2430;
  --muted: #6b7280;
  --line: #e3e6ea;
  --brand: #b21f2d;
  --brand-ink: #ffffff;
  --ok: #1d7a46;
  --ok-bg: #e7f4ec;
  --err: #b21f2d;
  --err-bg: #fbeaec;
  --sel: #eef2ff;
  --sel-line: #6b78d6;
}

* { box-sizing: border-box; }

html, body { margin: 0; }

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.5;
  padding-bottom: env(safe-area-inset-bottom);
}

.hidden { display: none !important; }
.muted { color: var(--muted); }
.center { text-align: center; }
.spacer { flex: 1; }
.subtle { opacity: 0.7; font-size: 0.9rem; }

.topbar {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.7rem 1rem;
  background: var(--brand);
  color: var(--brand-ink);
  position: sticky;
  top: 0;
  z-index: 5;
}

.badge {
  font-size: 0.75rem;
  background: rgba(255, 255, 255, 0.18);
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
}

main {
  max-width: 640px;
  margin: 0 auto;
  padding: 1rem;
  display: grid;
  gap: 1rem;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1.1rem;
}

h2 { font-size: 1.25rem; margin: 0 0 0.3rem; }
h3 { font-size: 1.05rem; margin: 0 0 0.3rem; }

.row { display: flex; gap: 0.6rem; align-items: center; }
.row.between { justify-content: space-between; }
.nav { margin-top: 1rem; }

button {
  cursor: pointer;
  border-radius: 10px;
  border: 1px solid transparent;
  padding: 0.6rem 1rem;
  font: inherit;
  font-weight: 500;
}
button.primary { background: var(--brand); color: var(--brand-ink); }
button.ghost { background: transparent; border-color: var(--line); color: var(--ink); }
button.big { width: 100%; padding: 0.9rem; font-size: 1.05rem; margin-top: 0.5rem; }
button:disabled { opacity: 0.5; cursor: default; }

/* Sign-in form. */
.login-card { max-width: 420px; margin: 1.5rem auto; }
.staff-link { margin-top: 1.2rem; padding-top: 0.8rem; border-top: 1px solid var(--line); font-size: 0.85rem; }
label { display: block; font-size: 0.85rem; margin: 0.7rem 0 0.25rem; font-weight: 500; }
input[type="text"], input[type="password"] {
  width: 100%;
  padding: 0.65rem 0.7rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  font: inherit;
  background: #fff;
  color: inherit;
}
.error { color: var(--err); font-size: 0.9rem; margin: 0.6rem 0 0; }

.progress { height: 6px; background: var(--line); border-radius: 999px; margin: 0.5rem 0 1rem; overflow: hidden; }
.progress-fill { height: 100%; background: var(--brand); width: 0%; transition: width 0.2s; }

.qimage { display: block; max-width: 100%; max-height: 220px; margin: 0 auto 1rem; }
.prompt { font-size: 1.1rem; font-weight: 500; margin: 0 0 1rem; }

.options { display: grid; gap: 0.5rem; }
.option {
  text-align: left;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.75rem 0.9rem;
  width: 100%;
  font-weight: 400;
}
.option.selected { background: var(--sel); border-color: var(--sel-line); }
.option.correct { background: var(--ok-bg); border-color: var(--ok); }
.option.wrong { background: var(--err-bg); border-color: var(--err); }

table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 0.45rem 0.4rem; border-bottom: 1px solid var(--line); font-size: 0.92rem; }

.attempts { list-style: none; padding: 0; margin: 0.5rem 0 0; }
.attempts li {
  display: flex; justify-content: space-between; align-items: center;
  padding: 0.55rem 0; border-bottom: 1px solid var(--line);
}
.pill { font-size: 0.8rem; padding: 0.15rem 0.6rem; border-radius: 999px; font-weight: 500; }
.pill.pass { background: var(--ok-bg); color: var(--ok); }
.pill.fail { background: var(--err-bg); color: var(--err); }

.result-pass { color: var(--ok); }
.result-fail { color: var(--err); }
.big-verdict { font-size: 1.6rem; font-weight: 600; margin: 0.2rem 0; }

.review-q { border: 1px solid var(--line); border-radius: 10px; padding: 0.7rem 0.8rem; margin-bottom: 0.6rem; }
.review-q .qp { font-weight: 500; margin: 0 0 0.4rem; }
.review-q .opt { padding: 0.15rem 0; font-size: 0.92rem; }
.review-q .opt.correct { color: var(--ok); font-weight: 500; }
.review-q .opt.wrong { color: var(--err); }
.review-q .exp { margin-top: 0.4rem; font-size: 0.88rem; color: var(--muted); }