:root {
  --bg: #f4f7f8;
  --bg-accent: #dff3f7;
  --panel: #ffffff;
  --panel-alt: #fdfefe;
  --text: #102a43;
  --muted: #486581;
  --primary: #0b7285;
  --primary-strong: #0a5f70;
  --secondary: #e3f2f5;
  --danger: #c92a2a;
  --border: #d9e2ec;
  --shadow: rgba(16, 42, 67, 0.08);
  --theme-toggle-bg: #ffffff;
  --theme-toggle-text: #102a43;
  --theme-toggle-border: #d9e2ec;
}

html[data-theme="dark"] {
  --bg: #0e141b;
  --bg-accent: #162230;
  --panel: #152231;
  --panel-alt: #1a2a3b;
  --text: #e2ecf5;
  --muted: #a2b8cb;
  --primary: #2ca2b8;
  --primary-strong: #3cb8d0;
  --secondary: #20384a;
  --danger: #ff6b6b;
  --border: #2b3f53;
  --shadow: rgba(0, 0, 0, 0.32);
  --theme-toggle-bg: #152231;
  --theme-toggle-text: #e2ecf5;
  --theme-toggle-border: #2b3f53;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top right, var(--bg-accent), var(--bg));
}

.container {
  max-width: 780px;
  margin: 2rem auto;
  padding: 0 1rem;
}

.container.wide { max-width: 1200px; }

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.2rem;
  box-shadow: 0 8px 24px var(--shadow);
}

.grid.two {
  display: grid;
  gap: 1rem;
  grid-template-columns: 1fr;
}

@media (min-width: 960px) {
  .grid.two { grid-template-columns: 1fr 1fr; }
}

h1, h2, h3 { margin-top: 0; }
label { display: block; margin-top: 0.6rem; margin-bottom: 0.2rem; font-weight: 700; }
input, textarea {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.65rem 0.75rem;
  font-size: 1rem;
}

textarea { resize: vertical; }

.btn {
  display: inline-block;
  border: none;
  border-radius: 10px;
  background: var(--primary);
  color: #fff;
  padding: 0.75rem 1rem;
  margin-top: 0.8rem;
  cursor: pointer;
  font-weight: 700;
  text-decoration: none;
}

.btn:hover { background: var(--primary-strong); }
.btn-secondary { background: #295d75; }
.btn-ghost { background: transparent; color: var(--primary); border: 1px solid var(--primary); }
.btn-small { margin-top: 0; padding: 0.35rem 0.7rem; font-size: 0.9rem; }

.row { display: flex; gap: 0.75rem; align-items: center; }
.between { justify-content: space-between; }
.stack { display: flex; flex-direction: column; }
.list { display: grid; gap: 0.55rem; }
.card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.8rem;
  background: var(--panel);
}

.question-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.7rem;
  background: var(--panel-alt);
}

.question-toolbar {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  margin-bottom: 0.45rem;
}

.answers-grid {
  display: grid;
  gap: 0.45rem;
  margin-top: 0.45rem;
}

.answer-row {
  display: grid;
  grid-template-columns: 28px 1fr;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
}

.answer-row .answer-text {
  margin: 0;
}

.correct-radio {
  width: 21px;
  height: 21px;
  margin: 0;
  cursor: pointer;
}

.answer-grid {
  display: grid;
  gap: 0.65rem;
  grid-template-columns: 1fr;
  margin-top: 0.8rem;
}

@media (min-width: 680px) {
  .answer-grid { grid-template-columns: 1fr 1fr; }
}

.answer-btn {
  text-align: left;
  font-size: 1.05rem;
  min-height: 60px;
}

.badge {
  display: inline-block;
  background: var(--secondary);
  color: var(--primary-strong);
  padding: 0.3rem 0.6rem;
  border-radius: 999px;
  font-weight: 700;
}

.muted { color: var(--muted); }
.hidden { display: none !important; }
.gap-top { margin-top: 1rem; }
.error { color: var(--danger); font-weight: 700; }

.theme-toggle {
  position: fixed;
  top: 12px;
  right: 12px;
  z-index: 9999;
  border: 1px solid var(--theme-toggle-border);
  border-radius: 999px;
  background: var(--theme-toggle-bg);
  color: var(--theme-toggle-text);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 0.42rem 0.75rem;
  cursor: pointer;
  box-shadow: 0 6px 18px var(--shadow);
}

.theme-toggle:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.quiz-list-item {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--panel);
  color: var(--text);
  padding: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  text-align: left;
}

.quiz-list-item:hover {
  border-color: var(--primary);
}

.quiz-list-title {
  font-weight: 700;
}

.run-top {
  text-align: center;
  margin-top: 0.8rem;
}

.run-code {
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  margin-top: 0.3rem;
}

.run-center {
  text-align: center;
  margin-top: 1.1rem;
  margin-bottom: 0.5rem;
}

.run-count {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1;
}