:root {
  color-scheme: light;
  font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --surface: #ffffff;
  --muted: #475467;
  --border: #e4e7ec;
  --accent: #4c6ef5;
  --accent-dark: #2643dc;
  --bg: radial-gradient(circle at 10% 20%, #fef7f1, #f2f4ff, #f7f7fb);
  --code-bg: #0f172a;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: #101828;
}

.shell {
  max-width: 1080px;
  margin: 0 auto;
  padding: 3rem 1.5rem 4rem;
}

.hero {
  text-align: center;
  margin-bottom: 2.5rem;
}

.hero h1 {
  font-size: clamp(2.4rem, 3vw, 3.2rem);
  margin: 0.4rem 0;
}

.hero .lede {
  color: var(--muted);
  margin: 0 auto;
  max-width: 640px;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.8rem;
  color: #8287a4;
  margin: 0;
}

.panel {
  background: var(--surface);
  border-radius: 24px;
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: 0 25px 60px rgba(15, 23, 42, 0.12);
}

.panel-heading {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2rem;
  align-items: baseline;
  margin-bottom: 1.5rem;
}

.panel-heading h2 {
  margin: 0.2rem 0 0;
}

.formula {
  margin-left: auto;
  font-family: "JetBrains Mono", SFMono-Regular, Consolas, monospace;
  font-size: 1rem;
  padding: 0.4rem 0.75rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: #f9fafb;
}

.triple-select {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.triple-select label {
  font-weight: 600;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  color: #1d2939;
}

.triple-select select {
  padding: 0.65rem 0.8rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  font-size: 1rem;
  background: #f8f9ff;
  font-weight: 500;
}

button {
  border: none;
  border-radius: 999px;
  padding: 0.85rem 1.7rem;
  font-size: 1rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

button.primary {
  background: var(--accent);
  color: white;
  box-shadow: 0 15px 35px rgba(76, 110, 245, 0.35);
}

button.primary:hover {
  background: var(--accent-dark);
  transform: translateY(-2px);
}

button.primary.ghost {
  background: transparent;
  color: var(--accent);
  border: 1px solid rgba(76, 110, 245, 0.35);
  box-shadow: none;
}

button.primary.ghost:hover {
  background: rgba(76, 110, 245, 0.08);
}

.single-output,
.multi-output {
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 1.5rem;
  background: linear-gradient(180deg, #fdfbff, #f8f8ff);
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.highlight {
  display: grid;
  gap: 0.6rem;
}

.highlight p {
  margin: 0;
  color: var(--muted);
}

.io-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 0.8rem 1.2rem;
  margin: 0;
}

.io-grid dt {
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #9aa1b5;
  margin: 0;
}

.io-grid dd {
  margin: 0;
  font-weight: 600;
  color: #1f2544;
}

.code-split {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.code-split article {
  border-radius: 16px;
  background: var(--code-bg);
  color: #d1e0ff;
  display: flex;
  flex-direction: column;
  min-height: 220px;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.05);
}

.code-split header {
  padding: 0.9rem 1.1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.code-split header strong {
  display: block;
  color: white;
}

.code-split pre {
  margin: 0;
  padding: 1rem 1.1rem;
  font-size: 0.9rem;
  font-family: "JetBrains Mono", SFMono-Regular, Consolas, monospace;
  white-space: pre-wrap;
  overflow-y: auto;
  flex: 1;
}

.combo-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  margin: 1.5rem 0;
}

.combo-card {
  border: 1px solid rgba(76, 110, 245, 0.2);
  border-radius: 16px;
  padding: 1rem;
  background: #f8f9ff;
  cursor: pointer;
  transition: border 160ms ease, box-shadow 160ms ease;
}

.combo-card h3 {
  margin: 0.2rem 0 0.3rem;
}

.combo-card p {
  margin: 0;
  color: var(--muted);
}

.combo-card.active {
  border-color: var(--accent);
  box-shadow: 0 18px 30px rgba(76, 110, 245, 0.18);
}

.combo-card button {
  margin-top: 0.75rem;
  width: 100%;
  border-radius: 12px;
  background: var(--surface);
  color: var(--accent);
  border: 1px solid rgba(76, 110, 245, 0.25);
}

.combo-card button:hover {
  background: rgba(76, 110, 245, 0.08);
}

.multi-output pre {
  background: #0e121c;
  color: #cfd9ff;
  border-radius: 16px;
  padding: 1rem;
  font-family: "JetBrains Mono", SFMono-Regular, Consolas, monospace;
  margin: 0;
  max-height: 240px;
  overflow-y: auto;
}

@media (max-width: 600px) {
  .panel {
    padding: 1.5rem;
  }

  .panel-heading {
    flex-direction: column;
    align-items: flex-start;
  }

  .formula {
    margin-left: 0;
  }
}