1、修改文件  setting.js

2、修改的文件路径  ruoyi-web/src/store/modules/setting.js

3、默认主题颜色 '#409EFF'，改新的颜色值，刷新就好了

4、修改主题颜色 还可以用户自己更换，但这个更换只是存储在浏览器中，清除缓存之后还是会使用默认的主题色

const state = {
  title: '',
  theme: storageSetting.theme || '#409EFF',
  sideTheme: storageSetting.sideTheme || sideTheme,
  showSettings: showSettings,
  topNav: storageSetting.topNav === undefined ? topNav : storageSetting.topNav,
  tagsView: storageSetting.tagsView === undefined ? tagsView : storageSetting.tagsView,
  fixedHeader: storageSetting.fixedHeader === undefined ? fixedHeader : storageSetting.fixedHeader,
  sidebarLogo: storageSetting.sidebarLogo === undefined ? sidebarLogo : storageSetting.sidebarLogo,
  dynamicTitle: storageSetting.dynamicTitle === undefined ? dynamicTitle : storageSetting.dynamicTitle
}

5、在布局设置中可以更换主题色