:root {
  --bg: #0b1220;
  --panel: #121a2b;
  --panel-2: #182338;
  --text: #e8eefc;
  --muted: #9aa8c7;
  --accent: #5b9dff;
  --accent-2: #3dd6c6;
  --warn: #f0c14b;
  --border: rgba(255, 255, 255, 0.08);
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --radius: 16px;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(91, 157, 255, 0.16), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(61, 214, 198, 0.1), transparent 50%),
    var(--bg);
}

.wrap {
  max-width: 920px;
  margin: 0 auto;
  padding: 2rem 1.25rem 3rem;
}

.eyebrow {
  margin: 0;
  color: var(--accent-2);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.75rem;
  font-weight: 700;
}

.hero h1 {
  margin: 0.35rem 0 0.75rem;
  font-size: clamp(1.75rem, 4vw, 2.35rem);
  letter-spacing: -0.02em;
}

.lede {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
  font-size: 1.05rem;
}

.lede a { color: var(--accent); }

.banner {
  margin: 1rem 0 0;
  padding: 0.7rem 0.9rem;
  border-radius: 10px;
  border: 1px solid rgba(240, 193, 75, 0.35);
  background: rgba(240, 193, 75, 0.08);
  color: var(--warn);
  font-size: 0.9rem;
  line-height: 1.45;
}

.banner a { color: var(--accent); }

.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-top: 1.75rem;
}

@media (max-width: 700px) {
  .grid { grid-template-columns: 1fr; }
}

.card {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
  background: linear-gradient(180deg, var(--panel), var(--panel-2));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.15rem 1.2rem 1.25rem;
  transition: border-color 0.15s ease, transform 0.15s ease;
}

.card:hover {
  border-color: rgba(91, 157, 255, 0.45);
  transform: translateY(-2px);
}

.card.primary {
  border-color: rgba(61, 214, 198, 0.35);
  grid-column: 1 / -1;
}

.tag {
  align-self: flex-start;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent-2);
  margin-bottom: 0.45rem;
}

.card h2 {
  margin: 0 0 0.45rem;
  font-size: 1.2rem;
}

.card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.5;
  flex: 1;
}

.go {
  margin-top: 0.9rem;
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--accent);
}

.panel {
  margin-top: 1.25rem;
  background: linear-gradient(180deg, var(--panel), var(--panel-2));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.15rem 1.25rem 1.3rem;
}

.panel h2 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
}

.muted {
  color: var(--muted);
  line-height: 1.5;
  font-size: 0.92rem;
  margin: 0 0 0.75rem;
}

.muted code, .foot code {
  font-size: 0.85em;
  background: rgba(0, 0, 0, 0.3);
  padding: 0.1em 0.35em;
  border-radius: 4px;
}

.links {
  margin: 0;
  padding-left: 1.2rem;
  color: var(--muted);
  line-height: 1.55;
  font-size: 0.92rem;
}

.links a { color: var(--accent); }
.links li { margin-bottom: 0.45rem; }

.steps {
  margin: 0;
  padding-left: 1.25rem;
  color: var(--muted);
  line-height: 1.55;
  font-size: 0.92rem;
}

.steps li { margin-bottom: 0.45rem; }
.steps a { color: var(--accent); }

.foot {
  margin-top: 2rem;
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.5;
}

.foot a { color: var(--accent); }

/* Shared note pages */
.note-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}

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

.note h1 {
  margin: 0.2rem 0 0.75rem;
  font-size: clamp(1.5rem, 3vw, 2rem);
}

.note h2 {
  margin: 1.5rem 0 0.5rem;
  font-size: 1.15rem;
  color: var(--accent);
}

.note p, .note li {
  color: var(--muted);
  line-height: 1.55;
  font-size: 0.95rem;
}

.note strong { color: var(--text); }

.note table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin: 0.75rem 0 1rem;
}

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

.note th {
  color: var(--text);
  background: rgba(0, 0, 0, 0.25);
}

.note .cta {
  display: inline-block;
  margin-top: 0.5rem;
  padding: 0.55rem 1rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #061018;
  font-weight: 700;
  text-decoration: none;
}

/* Study-note figures */
.note figure.fig {
  margin: 1rem 0 1.25rem;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 14px;
  overflow: hidden;
  background: rgba(0, 0, 0, 0.2);
  box-shadow: var(--shadow);
}

.note figure.fig img,
.note figure.fig svg,
.note figure.fig object {
  display: block;
  width: 100%;
  height: auto;
  vertical-align: middle;
}

.note figure.fig figcaption {
  margin: 0;
  padding: 0.65rem 0.9rem 0.75rem;
  font-size: 0.82rem;
  line-height: 1.45;
  color: var(--muted);
  border-top: 1px solid var(--border);
  background: rgba(0, 0, 0, 0.18);
}

.note figure.fig figcaption strong {
  color: var(--text);
}