:root {
  --bg: #fafaf8;
  --text: #1f2937;
  --muted: #6b7280;
  --accent: #0f766e;
  --border: #e5e7eb;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 640px;
  margin: 0 auto;
  padding: 5rem 1.5rem 3rem;
}

.hero {
  margin-bottom: 3.5rem;
}

.mark {
  width: 3rem;
  height: 3rem;
  border-radius: 0.5rem;
  background: var(--accent);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
}

h1 {
  font-size: 2rem;
  font-weight: 650;
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-bottom: 0.75rem;
}

.pa {
  color: var(--muted);
  font-weight: 500;
}

.tagline {
  font-size: 1.125rem;
  color: var(--muted);
}

section {
  margin-bottom: 2.5rem;
}

h2 {
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.15s ease;
}

a:hover {
  border-bottom-color: var(--accent);
}

footer {
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
  margin-top: 4rem;
  font-size: 0.875rem;
  color: var(--muted);
}