Spring boot,Sercurity failed to load css file

spring boot cannot load the css file that uses the thymeleaf, page. The program uses sercurity for login verification.
css file path resources/static/css/bootstrap.min1.css
the load statement in the html file is as follows:
< link th:href= "@ {css/bootstrap.min1.css}" rel= "stylesheet" / >
or < link th:href= "@ {.. / static/css/bootstrap.min1.css}" rel= "stylesheet" / >

the version of 2.0.2.RELEASE used by spring boot

background error report:
Refused to apply style from" http://localhost:8080/login" because its MIME type ("text/html") is not a supported stylesheet MIME type, and strict MIME checking is enabled.

Program Code:
login.html File

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">

<head>
    <meta content="text/html; charset=UTF-8"/>
    <title></title>
    <!--<link rel="stylesheet" th:href="@{"http://apps.bdimg.com/libs/bootstrap/3.3.4/js/bootstrap.min.js"}"/>-->
    <link th:href="@{../static/css/bootstrap.min1.css}" rel="stylesheet" />
    <!--<link rel="stylesheet" th:href="@{css/bootstrap.min1.css}"/>-->
    <style type="text/css">
        body {
            padding-top: 50px;
        }

        .starter-template {
            padding: 40px 15px;
            text-align: center;
        }

        .nini{
            color: -sharp2e6da4;
        }
    </style>
</head>
<body>
    <nav class="navbar navbar-inverse navbar-fixed-top">
        <div class="container">
            <div class="navbar-header">
                <a class="navbar-brand" href="-sharp">Spring Security</a>
            </div>
            <div id="navbar" class="collapse navbar-collapse">
                <ul class="nav navbar-nav">
                    <li><a th:href="@{/}">  </a></li>
                </ul>
            </div><!--/.nav-collapse -->
        </div>
    </nav>
    <div class="container">
        <div class="starter-template">
            <p th:if="${param.logout}" class="bg-warning">
            <p th:if="${param.error}" class="bg-danger">
            <h2 class="nini"></h2>
            <form name="form" th:action="@{/login}" action="/login" method="POST">
                <div class="form-group">
                    <label for="username"></label>
                    <input type="text" class="form-control" name="username" value="" placeholder=""/>
                </div>
                <div class="form-group">
                    <label for="password"></label>
                    <input type="password" class="form-control" name="password" placeholder=""/>
                </div>
                <input type="submit" id="login" value="Login" class="btn btn-primary"/>
            </form>
        </div>
    </div>
</body>
</html>

WebMvcConfig.java

@Configuration
public class WebMvcConfig extends WebMvcConfigurationSupport {
    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        registry.addViewController("/login").setViewName("login");
    }
}

WebSercurityConfig.java

@Configuration
public class WebSercurityConfig extends WebSecurityConfigurerAdapter {


    @Bean
    UserDetailsService customUserService(){
        return new CustomUserService();
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(customUserService()).passwordEncoder(new BCryptPasswordEncoder());
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
                .anyRequest().authenticated()
                .and()
                .formLogin()
                    .loginPage("/login")
                    .failureUrl("/login?error")
                    .permitAll()
                .and()
                .logout().permitAll();
    }
}

public class CustomUserService implements UserDetailsService {
    @Autowired
    SysUserRepository userRepository;

    @Override
    public UserDetails loadUserByUsername(String s) throws UsernameNotFoundException {
        SysUser user = userRepository.findByUsername(s);
        if(user == null){
            throw new UsernameNotFoundException("");
        }
        return user;
    }
}

@Controller
public class HomeController {
    @RequestMapping("/")
    public String index(Model model){
        Msg msg = new Msg("","","");
        model.addAttribute("msg",msg);
        return "home";
    }
}

Java

Mar.21,2021

<!DOCTYPE HTML> <html xmlns:th="http://www.thymeleaf.org"> <head> <title></title> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <link th:href="@{/css/plugins/login/styles.css}" rel="stylesheet" type="text/css" /> </head>