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

body {
  font-family: -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: #f5f6fa;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 16px;
}

.container {
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  padding: 24px;
  width: 100%;
  max-width: 360px;
  text-align: center;
}

h1 { font-size: 22px; color: #333; margin-bottom: 20px; }

.form-group { text-align: left; margin-bottom: 20px; }

.form-group label {
  display: block;
  font-size: 13px;
  color: #666;
  margin-bottom: 6px;
}

.form-group input {
  width: 100%;
  padding: 10px 12px;
  font-size: 14px;
  border: 1px solid #ddd;
  border-radius: 8px;
  outline: none;
  transition: border-color 0.2s;
}

.form-group input:focus { border-color: #1677ff; }

.info {
  background: #f7f8fa;
  border-radius: 8px;
  padding: 12px;
  margin-bottom: 20px;
  font-size: 13px;
  color: #555;
  line-height: 1.8;
  text-align: left;
}

.check-btn {
  width: 100%;
  padding: 14px;
  font-size: 16px;
  color: #fff;
  background: #1677ff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s;
}

.check-btn:hover { background: #0958d9; }
.check-btn:disabled { background: #aac8f5; cursor: not-allowed; }

.result {
  margin-top: 16px;
  font-size: 14px;
  min-height: 20px;
}

.result.success { color: #52c41a; }
.result.error { color: #ff4d4f; }