:root {
  --bg: #f3f6fb;
  --ink: #0f172a;
  --muted: #4b5563;
  --brand: #005fcc;
  --brand-2: #0a84ff;
  --line: #d7e0ee;
  --good: #128a3c;
  --bad: #c12f2f;
  --card: #ffffff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 10% 10%, #d9e8ff 0, #d9e8ff 18%, transparent 18%),
    radial-gradient(circle at 90% 85%, #e6f4ff 0, #e6f4ff 22%, transparent 22%),
    var(--bg);
  min-height: 100vh;
}

.app {
  max-width: 920px;
  margin: 0 auto;
  padding: 24px 16px 32px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  box-shadow: 0 8px 28px rgba(0, 61, 138, 0.08);
  padding: 18px;
}

.hidden {
  display: none;
}

h1, h2 {
  margin: 0 0 10px;
}

p {
  margin: 0 0 12px;
  color: var(--muted);
}

label {
  display: block;
  margin-bottom: 6px;
  font-weight: 600;
}

input[type="text"] {
  width: 100%;
  border: 1px solid #b8c7de;
  border-radius: 10px;
  padding: 10px 12px;
  font-size: 16px;
  margin-bottom: 12px;
}

.row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.row-spread {
  justify-content: space-between;
  margin-top: 14px;
}

button {
  border: 1px solid var(--brand);
  background: linear-gradient(180deg, var(--brand-2), var(--brand));
  color: #fff;
  border-radius: 10px;
  padding: 10px 14px;
  font-weight: 700;
  cursor: pointer;
}

button.secondary {
  background: #fff;
  color: var(--brand);
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.hint {
  margin-top: 10px;
  font-size: 13px;
}

.divider {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 16px 0;
}

.subhead {
  margin: 0 0 8px;
  font-size: 18px;
}

.test-picker {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 10px;
  margin-top: 10px;
}

.test-card {
  border: 1px solid #d3def0;
  border-radius: 12px;
  padding: 10px;
  background: #fbfdff;
}

.test-title {
  font-weight: 700;
  margin-bottom: 8px;
  color: #173251;
}

.module-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.module-btn {
  border-radius: 8px;
  padding: 7px 9px;
  font-size: 12px;
  font-weight: 700;
}

.test-main-btn {
  margin-bottom: 8px;
  width: 100%;
}

.error {
  color: var(--bad);
  font-weight: 700;
}

.quiz-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
}

.question-tracker {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 14px;
}

.tracker-item {
  appearance: none;
  min-width: 44px;
  border: 1px solid #c8d8f0;
  background: #f8fbff;
  color: #31455f;
  border-radius: 999px;
  padding: 5px 10px;
  font-size: 12px;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  transition: background 120ms ease, border-color 120ms ease;
}

.tracker-item:hover {
  background: #f0f7ff;
  border-color: #98bbef;
}

.tracker-item.current {
  border-color: #2e7dfb;
  box-shadow: 0 0 0 2px rgba(46, 125, 251, 0.15);
}

.tracker-status {
  display: inline-flex;
  align-items: center;
  gap: 3px;
}

.tracker-status.reveal {
  opacity: 0;
  animation: tracker-fade-in 240ms ease-out forwards;
}

@keyframes tracker-fade-in {
  from {
    opacity: 0;
    transform: translateY(-2px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.tracker-mark.good {
  color: var(--good);
}

.tracker-mark.bad {
  color: var(--bad);
}

.tracker-answer {
  color: #4a5f79;
}

.pill {
  background: #e7f0ff;
  color: #003f91;
  border: 1px solid #bdd4fb;
  border-radius: 999px;
  font-size: 13px;
  padding: 6px 10px;
}

.article {
  border: 1px solid #dbe6f6;
  border-left: 4px solid #8bb5ff;
  border-radius: 10px;
  padding: 10px 12px;
  margin-bottom: 12px;
  color: #1e2a3b;
}

.question {
  margin: 0 0 12px;
  font-size: 20px;
}

.choices {
  display: grid;
  gap: 8px;
}

.choice-btn {
  text-align: left;
  border: 1px solid #c4d5ee;
  background: #fff;
  color: var(--ink);
  border-radius: 10px;
  padding: 10px 12px;
  font-weight: 500;
}

.choice-btn.active {
  border-color: #2e7dfb;
  background: #edf5ff;
}

.write-wrap {
  margin-bottom: 8px;
}

.result-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(120px, 1fr));
  gap: 10px;
  margin: 12px 0;
}

.result-box {
  border-radius: 12px;
  border: 1px solid;
  padding: 12px;
}

.result-box.right {
  border-color: #a9e5be;
  background: #ebf9f0;
}

.result-box.wrong {
  border-color: #f0b2b2;
  background: #fff0f0;
}

.result-label {
  font-size: 13px;
  color: #3b4557;
}

.result-value {
  font-size: 36px;
  font-weight: 800;
  line-height: 1;
}

.right .result-value {
  color: var(--good);
}

.wrong .result-value {
  color: var(--bad);
}

.review-list {
  margin-top: 8px;
  padding-left: 20px;
}

.review-list li {
  margin-bottom: 6px;
}

@media (max-width: 640px) {
  .app {
    padding: 14px 10px 20px;
  }

  .question {
    font-size: 18px;
  }

  .row-spread {
    justify-content: flex-start;
  }
}

article textarea {
  display: none !important;
}