/* STL Segmenter landing — neutral starting point. Iterate freely. */

:root {
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --text: #0f172a;
  --text-soft: #475569;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --border: #e2e8f0;
  --max-width: 960px;
}

* { box-sizing: border-box; }

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

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

/* nav */

.nav {
  display: flex; align-items: center; justify-content: space-between;
  max-width: var(--max-width); margin: 0 auto;
  padding: 20px 24px;
}
.brand { font-weight: 700; color: var(--text); font-size: 18px; }
.brand:hover { text-decoration: none; }
.nav nav { display: flex; gap: 16px; }
.link { color: var(--text-soft); font-weight: 500; }

/* hero */

main { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

.hero {
  padding: 60px 0 48px;
  text-align: center;
}
.hero h1 {
  margin: 0 0 20px;
  font-size: clamp(32px, 6vw, 56px);
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.hero .lede {
  max-width: 640px;
  margin: 0 auto 32px;
  font-size: 18px;
  color: var(--text-soft);
}
.hero .hint {
  margin-top: 16px;
  color: var(--text-soft);
  font-size: 14px;
}

.cta {
  display: inline-block;
  padding: 14px 28px;
  background: var(--accent);
  color: white;
  border-radius: 10px;
  font-weight: 600;
  font-size: 17px;
  transition: background 0.15s, transform 0.15s;
}
.cta:hover {
  background: var(--accent-hover);
  color: white;
  text-decoration: none;
  transform: translateY(-1px);
}
.cta:focus-visible {
  outline: 3px solid #93c5fd;
  outline-offset: 2px;
}

/* features */

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
  padding: 32px 0;
}
.features article {
  padding: 24px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 12px;
}
.features h2 {
  margin: 0 0 8px;
  font-size: 18px;
}
.features p {
  margin: 0;
  color: var(--text-soft);
  font-size: 15px;
}

/* how it works */

.how {
  padding: 40px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  margin-top: 32px;
}
.how h2 {
  margin: 0 0 20px;
  font-size: 24px;
}
.how ol {
  margin: 0;
  padding-left: 20px;
  color: var(--text-soft);
}
.how li {
  margin-bottom: 8px;
  padding-left: 4px;
}

/* secondary CTA */

.cta-block {
  text-align: center;
  padding: 64px 0;
}
.cta-block h2 {
  margin: 0 0 24px;
  font-size: 28px;
}

/* footer */

footer {
  text-align: center;
  padding: 32px 24px;
  color: var(--text-soft);
  border-top: 1px solid var(--border);
}
footer small { font-size: 13px; }
footer a { color: var(--text-soft); }

/* mobile */

@media (max-width: 600px) {
  .hero { padding: 40px 0 32px; }
  .cta { padding: 12px 24px; font-size: 16px; }
}