:root {
  --bg: #f8f9fb;
  --surface: #ffffff;
  --text: #1a1d26;
  --muted: #5c6370;
  --accent: #2563eb;
  --accent-soft: #dbeafe;
  --border: #e5e7eb;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 4px 16px rgba(0, 0, 0, 0.04);
  --font: "Segoe UI", system-ui, -apple-system, sans-serif;
  --mono: ui-monospace, "Cascadia Code", monospace;
  --max: 920px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  font-size: 16px;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}

.site-header .inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0.85rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.logo {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text);
  text-decoration: none;
}

.logo span { color: var(--accent); }

nav { display: flex; gap: 0.35rem; flex-wrap: wrap; }

nav a {
  padding: 0.4rem 0.75rem;
  border-radius: 8px;
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 500;
  text-decoration: none;
}

nav a:hover, nav a.active {
  background: var(--accent-soft);
  color: var(--accent);
  text-decoration: none;
}

main {
  max-width: var(--max);
  margin: 0 auto;
  padding: 2rem 1.25rem 4rem;
}

.hero {
  text-align: center;
  padding: 2.5rem 0 2rem;
}

.hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.35rem);
  margin: 0 0 0.75rem;
  letter-spacing: -0.02em;
}

.hero p {
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 540px;
  margin: 0 auto 1.5rem;
}

.hero-actions {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 0.65rem 1.25rem;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  transition: transform 0.15s, box-shadow 0.15s;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.35);
  text-decoration: none;
  color: #fff;
}

.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--accent);
  text-decoration: none;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.85rem;
  margin-top: 1.5rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.1rem;
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.15s, box-shadow 0.15s;
}

.card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow);
  text-decoration: none;
}

.card h3 {
  margin: 0 0 0.25rem;
  font-size: 0.98rem;
}

.card p {
  margin: 0;
  font-size: 0.82rem;
  color: var(--muted);
}

.section-title {
  font-size: 1.15rem;
  margin: 2.5rem 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--accent-soft);
}

.content {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem 2rem;
  box-shadow: var(--shadow);
}

.content h1 { font-size: 1.75rem; margin-top: 0; }
.content h2 { font-size: 1.3rem; margin-top: 2rem; border-bottom: 1px solid var(--border); padding-bottom: 0.35rem; }
.content h3 { font-size: 1.08rem; margin-top: 1.5rem; }

.content blockquote {
  margin: 1rem 0;
  padding: 0.75rem 1rem;
  border-left: 4px solid var(--accent);
  background: var(--accent-soft);
  color: var(--muted);
  border-radius: 0 8px 8px 0;
}

.content table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin: 1rem 0;
  display: block;
  overflow-x: auto;
}

.content th, .content td {
  border: 1px solid var(--border);
  padding: 0.5rem 0.65rem;
  text-align: left;
}

.content th {
  background: var(--bg);
  font-weight: 600;
}

.content ul, .content ol { padding-left: 1.35rem; }
.content li { margin: 0.3rem 0; }

.content code {
  font-family: var(--mono);
  font-size: 0.88em;
  background: var(--bg);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
}

.content pre {
  background: #1e293b;
  color: #e2e8f0;
  padding: 1rem;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 0.85rem;
}

.content pre code { background: none; padding: 0; color: inherit; }

.content hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

.answers-wrap { margin-top: 0; border-top: 3px solid var(--accent); }

.answers-section h2 {
  margin-top: 0;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.band-tag {
  font-size: 0.75rem;
  font-weight: 600;
  background: var(--accent-soft);
  color: var(--accent);
  padding: 0.2rem 0.6rem;
  border-radius: 6px;
}

.answers-section h3 {
  font-size: 1.05rem;
  margin: 2rem 0 1rem;
  color: var(--accent);
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.35rem;
}

.qa-item {
  margin-bottom: 1.25rem;
  padding: 1rem 1.15rem;
  background: var(--bg);
  border-radius: 8px;
  border-left: 3px solid var(--accent);
}

.qa-q {
  font-weight: 600;
  margin: 0 0 0.6rem;
  color: var(--text);
}

.qa-a {
  margin: 0 0 0.65rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.qa-a:last-child { margin-bottom: 0; }

.site-footer {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
  margin-top: 2rem;
}

.breadcrumb {
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 1.25rem;
}

.breadcrumb a { color: var(--muted); }

@media (max-width: 640px) {
  .content { padding: 1.25rem; }
  main { padding-top: 1.25rem; }
}