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

body {
  background: #fff;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  color: #111;
  height: 100vh;
  display: flex;
  flex-direction: column;
}

nav {
  display: flex;
  border-bottom: 1px solid #e5e5e5;
  padding: 0 2rem;
}

.tab {
  padding: 1rem 1.5rem;
  text-decoration: none;
  color: #888;
  font-size: 0.95rem;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  transition: color 0.2s, border-color 0.2s;
}

.tab:hover {
  color: #111;
}

.tab.active {
  color: #111;
  border-bottom-color: #111;
  font-weight: 500;
}

main {
  flex: 1;
}

.page {
  display: none;
  height: 100%;
}

.page.active {
  display: block;
}

#home {
  display: flex;
  align-items: center;
  justify-content: center;
}

#home h1 {
  font-size: 3rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}