:root {
  --accent: #0366d6;
  --muted: #6b7280;
  --bg: #f7fafc;
}

* {
  box-sizing: border-box;
}

body {
  font-family: Inter, system-ui, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.5;
  margin: 0;
  background: var(--bg);
  color: #111;
}

header {
  background: #fff;
  border-bottom: 1px solid #e6e9ee;
  position: sticky;
  top: 0;
  z-index: 10;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px;
}

.header-container {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand {
  font-weight: 700;
  color: var(--accent);
  margin-right: auto;
}

.nav-links {
  display: flex;
  gap: 8px;
}

.nav-links a {
  padding: 8px 12px;
  border-radius: 8px;
  text-decoration: none;
  color: inherit;
}

.nav-links a.active {
  background: rgba(3, 102, 214, 0.1);
  color: var(--accent);
}

main {
  padding: 28px 20px;
}

.hero {
  background: #fff;
  padding: 24px;
  border-radius: 12px;
  box-shadow: 0 6px 18px rgba(12, 18, 20, 0.04);
}

h1 {
  margin: 0 0 8px 0;
}

footer {
  padding: 20px;
  text-align: center;
  color: var(--muted);
  font-size: 14px;
}

.btn {
  display: inline-block;
  padding: 8px 12px;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
}

@media (max-width: 900px) {
  .header-container {
    flex-wrap: wrap;
  }
}