:root {
  color-scheme: light dark;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #f6f7f9;
  color: #18212f;
}

body {
  margin: 0;
  min-height: 100vh;
  background: #f6f7f9;
  color: #18212f;
}

.shell {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px;
}

.panel {
  background: #ffffff;
  border: 1px solid #d9dee7;
  border-radius: 8px;
  padding: 24px;
  box-shadow: 0 10px 30px rgba(19, 33, 54, 0.08);
}

.narrow {
  max-width: 440px;
  margin: 8vh auto;
}

.center {
  text-align: center;
}

.stack {
  display: grid;
  gap: 16px;
}

h1, h2 {
  margin-top: 0;
}

label {
  display: grid;
  gap: 6px;
  font-weight: 700;
}

input, textarea, select, button, .button {
  font: inherit;
}

input, textarea, select {
  border: 1px solid #b8c0cc;
  border-radius: 8px;
  padding: 10px 12px;
  background: #fff;
  color: #18212f;
}

button, .button {
  border: 1px solid #9aa7b8;
  border-radius: 8px;
  padding: 10px 14px;
  background: #eef1f5;
  color: #18212f;
  cursor: pointer;
  text-decoration: none;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.55;
}

.primary {
  background: #0d6b57;
  border-color: #0d6b57;
  color: #fff;
}

.secondary {
  background: #254f7a;
  border-color: #254f7a;
  color: #fff;
}

.danger {
  background: #a43831;
  border-color: #a43831;
  color: #fff;
}

.error {
  color: #a43831;
  font-weight: 700;
}

.status, .score {
  font-size: 1.2rem;
  font-weight: 800;
}

.spinner {
  width: 36px;
  height: 36px;
  margin: 20px auto 0;
  border: 4px solid #cbd3df;
  border-top-color: #0d6b57;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.quiz-panel h1 {
  font-size: clamp(1.5rem, 4vw, 2.5rem);
}

.topline {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  font-weight: 800;
}

.bar {
  height: 12px;
  background: #e0e6ef;
  border-radius: 999px;
  overflow: hidden;
  margin: 12px 0 24px;
}

.bar span {
  display: block;
  height: 100%;
  width: 100%;
  background: #0d6b57;
  transition: width 0.2s linear;
}

.answers {
  display: grid;
  gap: 12px;
}

.answer {
  display: grid;
  grid-template-columns: 42px 1fr;
  gap: 12px;
  min-height: 68px;
  align-items: center;
  text-align: left;
  background: #fff;
}

.answer strong {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: #254f7a;
  color: #fff;
}

.histogram {
  display: grid;
  gap: 10px;
  margin: 16px 0;
}

.hist-row {
  display: grid;
  grid-template-columns: 72px 1fr 48px;
  gap: 10px;
  align-items: center;
}

meter {
  width: 100%;
}

.leaderboard {
  display: grid;
  gap: 8px;
  padding-left: 0;
  list-style: none;
}

.leaderboard li {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid #e2e7ee;
}

.celebration {
  outline: 6px solid #f2c94c;
}

.admin-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  min-height: 100vh;
}

.sidebar {
  padding: 20px;
  background: #223044;
  color: #fff;
}

.sidebar .list {
  display: grid;
  gap: 8px;
  margin-bottom: 24px;
}

.sidebar button {
  width: 100%;
  text-align: left;
}

.workspace {
  padding: 24px;
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 16px 0;
}

.roster {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.roster span {
  border: 1px solid #ccd4df;
  border-radius: 999px;
  padding: 6px 10px;
}

.qr {
  width: min(280px, 100%);
  height: auto;
  background: #fff;
  padding: 12px;
}

@media (max-width: 720px) {
  .shell, .workspace {
    padding: 14px;
  }

  .admin-layout {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
  }

  .panel {
    padding: 18px;
  }
}

@media (prefers-color-scheme: dark) {
  :root, body {
    background: #10141b;
    color: #edf1f7;
  }

  .panel, input, textarea, select, .answer {
    background: #171d27;
    color: #edf1f7;
    border-color: #344052;
  }

  button, .button {
    background: #263246;
    color: #edf1f7;
    border-color: #4a586d;
  }
}