:root {
  --green: #0b6e4f;
  --green-dark: #095a40;
  --blue: #1d4e89;
  --yellow: #f4c430;
  --bg: #f4f6f8;
  --card: #ffffff;
  --text: #1f2a37;
  --muted: #5b6775;
  --border: #e2e8f0;
  --ok: #15803d;
  --ok-bg: #dcfce7;
  --err: #b91c1c;
  --err-bg: #fee2e2;
  --radius: 14px;
  --shadow: 0 6px 24px rgba(15, 23, 42, 0.08);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.55;
}

.container {
  width: 100%;
  max-width: 760px;
  margin: 0 auto;
  padding: 0 18px;
}

.hidden { display: none !important; }

/* Top bar */
.topbar {
  background: linear-gradient(135deg, var(--green), var(--green-dark));
  color: #fff;
}
.topbar__inner {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 14px 18px;
}
.brand { font-size: 1.1rem; font-weight: 500; }
.brand strong { font-weight: 800; }
.brand__tag {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  background: rgba(255, 255, 255, 0.18);
  padding: 2px 8px;
  border-radius: 999px;
}

/* Cards / screens */
.card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 26px;
  margin: 24px 0;
}

h1 { font-size: 1.6rem; margin: 0 0 8px; }
h2 { font-size: 1.25rem; }
.lead { color: var(--muted); margin-top: 0; }

/* Form fields */
.field { margin: 18px 0; }
.field label { display: block; font-weight: 600; margin-bottom: 6px; font-size: 0.95rem; }
select {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
  font-size: 1rem;
  color: var(--text);
}
.checkbox {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.95rem;
  color: var(--muted);
  margin: 14px 0 20px;
  cursor: pointer;
}
.checkbox input { width: 18px; height: 18px; accent-color: var(--green); }

/* Buttons */
.btn {
  display: inline-block;
  border: none;
  border-radius: 10px;
  padding: 13px 20px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform .05s ease, background .15s ease, opacity .15s ease;
}
.btn:active { transform: translateY(1px); }
.btn--primary { background: var(--green); color: #fff; }
.btn--primary:hover { background: var(--green-dark); }
.btn--ghost { background: #eef2f6; color: var(--text); }
.btn--ghost:hover { background: #e2e8f0; }
.btn--block { width: 100%; margin-top: 6px; }
.btn:disabled { opacity: .45; cursor: not-allowed; }

.disclaimer {
  margin-top: 22px;
  font-size: 0.82rem;
  color: var(--muted);
  background: #fffbeb;
  border: 1px solid #fde68a;
  border-radius: 10px;
  padding: 12px 14px;
}

/* Quiz */
.quiz__top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 8px;
}
.quiz__timer { font-variant-numeric: tabular-nums; font-weight: 600; }
.progress {
  height: 8px;
  background: #e9eef3;
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: 18px;
}
.progress__bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--green), var(--blue));
  transition: width .25s ease;
}
.badge {
  display: inline-block;
  background: #e7f0ff;
  color: var(--blue);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 4px 10px;
  border-radius: 999px;
}
.quiz__question { margin: 12px 0 18px; line-height: 1.4; }
.quiz__image { margin: 0 0 18px; text-align: center; }
.quiz__image img {
  max-width: 100%;
  height: auto;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
}

.options { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.option {
  display: flex;
  align-items: center;
  gap: 12px;
  border: 2px solid var(--border);
  border-radius: 12px;
  padding: 14px 16px;
  cursor: pointer;
  background: #fff;
  transition: border-color .12s ease, background .12s ease;
}
.option:hover { border-color: #c3cfdd; }
.option.selected { border-color: var(--green); background: #f0fbf6; }
.option.correct { border-color: var(--ok); background: var(--ok-bg); }
.option.wrong { border-color: var(--err); background: var(--err-bg); }
.option__letter {
  flex: 0 0 28px;
  height: 28px;
  border-radius: 50%;
  background: #eef2f6;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.85rem;
}
.option.selected .option__letter { background: var(--green); color: #fff; }
.option.correct .option__letter { background: var(--ok); color: #fff; }
.option.wrong .option__letter { background: var(--err); color: #fff; }

.feedback {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: 10px;
  font-size: 0.92rem;
}
.feedback.ok { background: var(--ok-bg); color: var(--ok); }
.feedback.err { background: var(--err-bg); color: var(--err); }
.feedback strong { display: block; margin-bottom: 4px; }

.quiz__nav {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-top: 22px;
}
.quiz__nav .btn { flex: 1; }

/* Result */
.result-banner {
  text-align: center;
  font-weight: 800;
  font-size: 1.15rem;
  padding: 14px;
  border-radius: 12px;
  margin-bottom: 18px;
}
.result-banner.pass { background: var(--ok-bg); color: var(--ok); }
.result-banner.fail { background: var(--err-bg); color: var(--err); }
.result__title { text-align: center; margin: 0 0 16px; }
.result__score { text-align: center; margin-bottom: 22px; }
.result__big { font-size: 3rem; font-weight: 800; color: var(--green); line-height: 1; }
.result__total { font-size: 1.4rem; color: var(--muted); }
.result__pct { font-size: 1.1rem; color: var(--muted); margin-top: 6px; }
.result__time { font-size: 0.9rem; color: var(--muted); margin-top: 4px; }
.result__actions { display: grid; gap: 10px; }

/* Review */
.review { margin-top: 24px; display: grid; gap: 14px; }
.review__item {
  border: 1px solid var(--border);
  border-left-width: 5px;
  border-radius: 10px;
  padding: 14px 16px;
}
.review__item.ok { border-left-color: var(--ok); }
.review__item.err { border-left-color: var(--err); }
.review__q { font-weight: 600; margin: 0 0 8px; }
.review__a { font-size: 0.9rem; margin: 2px 0; }
.review__a.user-wrong { color: var(--err); }
.review__a.right { color: var(--ok); }
.review__exp { font-size: 0.86rem; color: var(--muted); margin-top: 8px; }

/* Footer */
.footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.82rem;
  padding: 24px 0 36px;
}
.footer p { margin: 0; }

@media (max-width: 480px) {
  .card { padding: 20px 16px; }
  h1 { font-size: 1.35rem; }
  .result__big { font-size: 2.4rem; }
}