width: 100vw; height: 100vh; display: flex; align-items: center; justify-content: center; background: url("images/login-bj.jpg") fixed no-repeat; background-size: cover; } 1. 2. 3. 4. 5. 6. 7. 8. 9. 透明度: .login-form { background-color: rgba(255, 255, 255, 0.8); /...