* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: #f7f9fa;
  color: #0f1419;
}

.app {
  min-height: 100vh;
}

.app-nav {
  background: white;
  border-bottom: 1px solid #e1e8ed;
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  height: 56px;
}

.nav-brand {
  font-size: 20px;
  font-weight: 700;
  color: #1da1f2;
  text-decoration: none;
}

.nav-brand:hover {
  color: #1991db;
}

.nav-links {
  display: flex;
  gap: 24px;
}

.nav-link {
  color: #536471;
  text-decoration: none;
  font-weight: 500;
  padding: 16px 0;
  border-bottom: 2px solid transparent;
  transition: all 0.2s ease;
}

.nav-link:hover {
  color: #0f1419;
}

.nav-link.active {
  color: #1da1f2;
  border-bottom-color: #1da1f2;
}

.app-main {
  min-height: calc(100vh - 56px);
  background-color: #f7f9fa;
}

@media (max-width: 768px) {
  .nav-container {
    padding: 0 16px;
  }

  .nav-links {
    gap: 16px;
  }
}