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

body {
   font-family: 'Microsoft YaHei', sans-serif;
   background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
   min-height: 100vh;
   display: flex;
   justify-content: center;
   align-items: center;
}

.login-container {
   background: white;
   border-radius: 12px;
   box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
   padding: 40px;
   width: 400px;
}

.login-title {
   text-align: center;
   font-size: 24px;
   font-weight: bold;
   color: #333;
   margin-bottom: 30px;
}

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

.form-group label {
   display: block;
   margin-bottom: 8px;
   color: #666;
   font-size: 14px;
}

.form-group input {
   width: 100%;
   padding: 12px 15px;
   border: 1px solid #ddd;
   border-radius: 8px;
   font-size: 14px;
   transition: border-color 0.3s;
}

.form-group input:focus {
   outline: none;
   border-color: #667eea;
}

.captcha-group {
   display: flex;
   gap: 10px;
}

.captcha-group input {
   flex: 1;
}

.captcha-img {
   width: 120px;
   height: 44px;
   border-radius: 8px;
   cursor: pointer;
   margin-top: 25px;
}

.login-btn {
   width: 100%;
   padding: 14px;
   background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
   border: none;
   border-radius: 8px;
   color: white;
   font-size: 16px;
   font-weight: bold;
   cursor: pointer;
   transition: opacity 0.3s;
}

.login-btn:hover {
   opacity: 0.9;
}

.error-msg {
   color: #e74c3c;
   font-size: 12px;
   margin-top: 10px;
   text-align: center;
   display: none;
}