:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --text: #16202c;
  --muted: #5a6675;
  --border: #dfe3e8;
  --accent: #0b7a75;
  --accent-hover: #09625e;
  --accent-text: #ffffff;
  --accent-soft: #e2f2f1;
  --peak: #b7c0cb;
  --highlight: #d9480f;
  --shadow: 0 1px 2px rgb(16 24 40 / 0.05), 0 8px 24px rgb(16 24 40 / 0.06);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f141a;
    --surface: #171e26;
    --text: #e6ebf0;
    --muted: #9aa6b4;
    --border: #2a333d;
    --accent: #3cbcb4;
    --accent-hover: #5ccfc8;
    --accent-text: #06201f;
    --accent-soft: #15302f;
    --peak: #475260;
    --highlight: #ff8a4c;
    --shadow: 0 1px 2px rgb(0 0 0 / 0.3), 0 8px 24px rgb(0 0 0 / 0.25);
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

main {
  max-width: 1040px;
  margin: 0 auto;
  padding: 64px 24px 32px;
}

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

h1, h2, h3 { line-height: 1.2; margin: 0; }

/* hero */
.hero {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 48px;
  align-items: center;
  padding-bottom: 56px;
}

.eyebrow {
  margin: 0 0 12px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}

h1 {
  font-size: clamp(2.4rem, 5vw, 3.4rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.lede {
  margin: 16px 0 32px;
  font-size: 1.15rem;
  color: var(--muted);
  max-width: 34em;
}

.launch button {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 16px 28px;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: var(--accent-text);
  font: inherit;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: background 0.15s, transform 0.15s;
}
.launch button:hover:not(:disabled) { background: var(--accent-hover); transform: translateY(-1px); }
.launch button:focus-visible { outline: 3px solid var(--accent-soft); outline-offset: 3px; }
.launch button:disabled { opacity: 0.7; cursor: progress; }
.launch button svg { transition: transform 0.15s; }
.launch button:hover:not(:disabled) svg { transform: translateX(3px); }

.status {
  margin: 14px 0 0;
  font-size: 0.9rem;
  color: var(--muted);
}

/* decorative spectrum */
.spectrum {
  margin: 0;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
}
.spectrum svg { display: block; width: 100%; height: auto; }
.spectrum line { stroke-width: 4; stroke-linecap: round; }
.spectrum .axis { stroke: var(--border); stroke-width: 2; }
.spectrum .peaks line { stroke: var(--peak); }
.spectrum .hit line { stroke: var(--highlight); }
.spectrum .hit .iso { opacity: 0.55; }
.spectrum .tag rect { fill: var(--accent-soft); }
.spectrum text { fill: var(--text); font-size: 12px; font-weight: 600; }
.spectrum text.sub { fill: var(--muted); font-size: 10px; font-weight: 500; }
.spectrum .axis-label { fill: var(--muted); font-size: 11px; font-style: italic; font-weight: 400; }

/* features */
.features, .notes { padding: 40px 0; border-top: 1px solid var(--border); }
h2 { font-size: 1.35rem; margin-bottom: 24px; }

.cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.cards article {
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
}
.cards h3 { font-size: 1rem; margin-bottom: 8px; }
.cards p { margin: 0; font-size: 0.92rem; color: var(--muted); }

.notes ul { margin: 0; padding-left: 1.2em; color: var(--muted); max-width: 46em; }
.notes li + li { margin-top: 6px; }

footer {
  max-width: 1040px;
  margin: 0 auto;
  padding: 24px 24px 48px;
  font-size: 0.85rem;
  color: var(--muted);
}

/* narrower screens */
@media (max-width: 880px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 720px) {
  main { padding: 40px 16px 24px; }
  footer { padding: 24px 16px 40px; }
  .hero { grid-template-columns: 1fr; gap: 32px; padding-bottom: 40px; }
  .launch button { width: 100%; justify-content: center; }
}
@media (max-width: 480px) {
  .cards { grid-template-columns: 1fr; }
}