body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: #f9f9f9;
  color: #333;
}
.container {
  width: 90%;
  max-width: 960px;
  margin: 0 auto;
  padding: 20px;
}
header {
  background-color: #00ad51;
  color: white;
  padding: 10px 0;
}
header .logo {
  font-size: 24px;
  font-weight: bold;
  float: left;
  margin-left: 20px;
}
header nav {
  float: right;
  margin-right: 20px;
}
header nav a {
  color: white;
  margin-left: 20px;
  text-decoration: none;
}
header::after {
  content: "";
  display: block;
  clear: both;
}
main h1, main h2 {
  color: #008e43;
}
main section {
  margin-bottom: 30px;
}
form {
  display: flex;
  flex-direction: column;
  gap: 10px;
  max-width: 400px;
}
input[type="text"] {
  padding: 10px;
  font-size: 16px;
  border: 1px solid #ccc;
  border-radius: 4px;
}
button {
  padding: 10px;
  background-color: #008e43;
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}
button:hover {
  background-color: #003388;
}
table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 20px;
}
table, th, td {
  border: 1px solid #ccc;
}
th, td {
  padding: 10px;
  text-align: left;
}
pre {
  background-color: #f6f8fa;
  border: 1px solid #ddd;
  border-radius: 6px;
  padding: 1em;
  font-family: Consolas, Monaco, Menlo, monospace;
  font-size: 14px;
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-word;
  line-height: 1.6;
  color: #333;
}
textarea {
  width: 100%;
  padding: 10px;
  font-size: 14px;
  font-family: "Courier New", monospace;
  border: 1px solid #ccc;
  border-radius: 6px;
  resize: vertical;
  box-sizing: border-box;
}

.tips {
  margin: 8px 0 16px;
  color: #666;
  font-size: 14px;
  line-height: 1.5;
}
footer {
  text-align: center;
  background: #eee;
  padding: 15px 0;
  margin-top: 40px;
  font-size: 14px;
}
@media (max-width: 600px) {
  header .logo, header nav {
    float: none;
    text-align: center;
    margin: 10px 0;
  }
  header nav a {
    display: inline-block;
    margin: 0 10px;
  }
}