:root {
  --bg: #0f141a;
  --panel: #171e27;
  --line: #2a3544;
  --text: #e8edf3;
  --muted: #9aa7b6;
  --accent: #6ea8ff;
  --accent2: #74e0c0;
  --error: #ff7f86;
  --success: #56d364;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 "Segoe UI", Inter, system-ui, -apple-system, sans-serif;
}

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

button {
  cursor: pointer;
  border: none;
  font: inherit;
  padding: 12px 24px;
  border-radius: 8px;
  background: var(--accent);
  color: var(--bg);
  font-weight: 600;
  transition: opacity 0.2s;
}

button:hover { opacity: 0.9; }
button:disabled { opacity: 0.5; cursor: not-allowed; }

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 6%;
  border-bottom: 1px solid var(--line);
  background: var(--panel);
  position: sticky;
  top: 0;
  z-index: 100;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-weight: 700;
  font-size: 20px;
  color: var(--text);
}

.brand small {
  color: var(--muted);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 650;
}

nav {
  display: flex;
  gap: 32px;
  align-items: center;
}

nav a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  transition: color 0.2s;
}

nav a:hover { color: var(--accent); }
nav a.active { color: var(--accent2); }

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 56px 6% 72px;
}

footer {
  padding: 40px 6%;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
  text-align: center;
}

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

@media (max-width: 900px) {
  header { flex-direction: column; gap: 16px; }
  nav { gap: 16px; font-size: 12px; }
  main { padding: 40px 6%; }
}