* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, "Microsoft YaHei", sans-serif;
  background: #f5f7fb;
  color: #1f2937;
}

.site-header {
  padding: 48px 24px;
  color: #fff;
  background: #2563eb;
  text-align: center;
}

.site-header h1 {
  margin: 0;
}

.site-header p {
  margin-bottom: 0;
}

.container {
  max-width: 960px;
  min-height: 400px;
  margin: 0 auto;
  padding: 32px 24px;
}

.tool-card {
  padding: 24px;
  border-radius: 12px;
  background: #fff;
  box-shadow: 0 4px 12px rgb(0 0 0 / 8%);
}

.site-footer {
  padding: 24px;
  color: #6b7280;
  text-align: center;
}