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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  color: #222;
  line-height: 1.6;
}

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background: #1f2937;
  color: #fff;
}

.site-header .logo {
  font-weight: bold;
  font-size: 1.25rem;
}

.site-header nav a {
  color: #fff;
  text-decoration: none;
  margin-left: 1.5rem;
}

.site-header nav a:hover {
  text-decoration: underline;
}

.hero {
  text-align: center;
  padding: 4rem 2rem;
  background: #f3f4f6;
}

.hero h1 {
  font-size: 2.25rem;
  margin-bottom: 1rem;
}

.hero p {
  color: #555;
  margin-bottom: 1.5rem;
}

button#clickBtn {
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  background: #2563eb;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

button#clickBtn:hover {
  background: #1d4ed8;
}

.content {
  max-width: 700px;
  margin: 0 auto;
  padding: 3rem 2rem;
}

.content h2 {
  margin-bottom: 1rem;
}

.site-footer {
  text-align: center;
  padding: 1.5rem;
  background: #1f2937;
  color: #ccc;
  margin-top: 2rem;
}