:root {
  --bg-dark: #0f172a;
  --bg-light: #f5f7fa;
  --text-dark: #e0e7ff;
  --text-light: #1f2937;
  --accent-dark: #3b82f6;
  --accent-light: #2563eb;
  --border-dark: #334155;
  --border-light: #cbd5e1;
  --font-mono: 'Fira Code', monospace;
  --radius: 12px;
  --transition: 0.3s;
}

body {
  margin: 0;
  font-family: var(--font-mono);
  background-color: var(--bg-dark);
  color: var(--text-dark);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1rem;
  transition: background var(--transition), color var(--transition);
  text-align: center;
}

body.light {
  background-color: var(--bg-light);
  color: var(--text-light);
}

header {
  width: 100%;
  max-width: 900px;
  margin: 1rem auto 1.5rem;
  padding: 0.6rem 1rem;
  font-size: 0.9rem;
  line-height: 1.4;
  font-weight: 600;
  border-radius: var(--radius);
  background: rgba(59, 130, 246, 0.15);
  color: var(--accent-dark);
  user-select: none;
  transition: background var(--transition), color var(--transition);
}

body.light header {
  background: rgba(37, 99, 235, 0.15);
  color: var(--accent-light);
}

h1 {
  margin: 0 0 1rem;
  font-size: 2rem;
  user-select: none;
}

.controls {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  flex-wrap: nowrap;
  width: 100%;
  max-width: 800px;
}

.controls button {
  font-family: var(--font-mono);
  padding: 0.5rem 1rem;
  border: 2px solid var(--accent-dark);
  background: transparent;
  color: var(--text-dark);
  cursor: pointer;
  border-radius: var(--radius);
  transition: var(--transition);
  user-select: none;
  flex: 0 1 auto;
}

body.light .controls button {
  border-color: var(--accent-light);
  color: var(--text-light);
}

.controls button.active {
  background: var(--accent-dark);
  color: #fff;
}

body.light .controls button.active {
  background: var(--accent-light);
}

@media (max-width: 600px) {
  .controls {
    flex-wrap: wrap;
  }
  .controls button {
    flex: 1 1 45%;
    text-align: center;
  }
}

section {
  width: 100%;
  max-width: 900px;
  margin-bottom: 2rem;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.05);
  padding: 1rem;
  overflow-x: auto;
  transition: background var(--transition);
  text-align: left;
}

body.light section {
  background: #fff;
  box-shadow: 0 4px 10px rgba(0,0,0,0.05);
}

section h2 {
  margin-top: 0;
  margin-bottom: 0.5rem;
  font-weight: 700;
  user-select: none;
  text-align: center;
}

table {
  width: 100%;
  border-collapse: collapse;
  table-layout: fixed;
  min-width: 300px;
  margin: 0 auto;
}

th, td {
  padding: 0.6rem 0.8rem;
  border-bottom: 1px solid var(--border-dark);
  text-align: left;
  word-break: break-word;
  vertical-align: top;
  transition: border-color var(--transition);
}

body.light th, body.light td {
  border-color: var(--border-light);
}

th {
  font-weight: 600;
  width: 40%;
  color: var(--accent-dark);
  user-select: none;
}

body.light th {
  color: var(--accent-light);
}

tr {
  animation: fadeIn 0.4s ease-in-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

footer {
  font-size: 0.85rem;
  text-align: center;
  margin-top: auto;
  padding-top: 1rem;
  user-select: none;
  color: var(--text-dark);
  transition: color var(--transition);
}

body.light footer {
  color: var(--text-light);
}

footer a {
  color: inherit;
  text-decoration: underline;
}

footer a:hover {
  text-decoration: none;
}

.subhead {
  font-size: 0.95em;
  color: #9ca3af;
  margin-bottom: 0.3em;
  user-select: none;
  text-align: center;
}

@media (max-width: 768px) {
  section { padding: 0.8rem; }
  th, td { padding: 0.5rem 0.6rem; }
  h1 { font-size: 1.8rem; }
  .controls button { font-size: 0.9rem; padding: 0.4rem 0.8rem; }
}

@media (max-width: 480px) {
  h1 { font-size: 1.6rem; }
  .controls button { font-size: 0.85rem; padding: 0.35rem 0.7rem; }
  th, td { padding: 0.4rem 0.6rem; }
  section { padding: 0.6rem; }
  header { font-size: 0.8rem; }
}