Angular组件样式未生效问题排查求助

我正在开发一个Angular应用，遇到组件内定义的样式无法按预期生效的问题。已尝试多种排查步骤但均未解决，相同配置在新建Angular项目中可正常运行，因此怀疑现有项目配置存在问题。

组件配置 #

我创建了一个简单的Angular组件，通过内联样式将h1元素颜色设置为红色：

import { Component, OnInit, ViewEncapsulation } from '@angular/core';

@Component({
  selector: 'cm-test',
  templateUrl: './test.component.html',
  styles: [
    `h1 { color: red !important; }`
  ],
  encapsulation: ViewEncapsulation.None  // 已设置为None
})
export class TestComponent implements OnInit {

  constructor() { }

  ngOnInit(): void { }
}

HTML模板 #

组件的HTML模板仅包含一个h1元素：

<h1>test works!</h1>

问题详情 #

color: red !important样式未应用到h1元素上。尽管尝试了以下解决方案，样式仍未生效：

• 使用ViewEncapsulation.None（禁用组件级作用域）
• 使用::ng-deep（已弃用但仍可使用）
• 尝试不添加!important的color: red样式
• 通过浏览器开发者工具检查样式是否被覆盖
• 测试简单内联样式如h1 { color: red; }
• 清除浏览器缓存并重新构建Angular项目
• 将样式放入单独文件并通过styleUrls导入

angular.json配置 #

{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "cli": {
    "packageManager": "yarn",
    "analytics": "***"
  },
  "newProjectRoot": "projects",
  "projects": {
    "control-panel": {
      "projectType": "application",
      "schematics": {
        "@schematics/angular:component": {
          "style": "scss"
        }
      },
      "root": "",
      "sourceRoot": "src",
      "prefix": "cm",
      "architect": {
        "build": {
          "builder": "@angular-builders/custom-webpack:browser",
          "options": {
            "outputPath": "dist/",
            "index": "src/index.html",
            "main": "src/main.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "tsconfig.app.json",
            "inlineStyleLanguage": "scss",
            "assets": [
              "src/favicon.ico",
              "src/assets",
              "src/firebase-messaging-sw.js",
              "src/.htaccess",
              {
                "glob": "**/*",
                "input": "./node_modules/leaflet/dist/images",
                "output": "assets/"
              }
            ],
            "styles": [
              "src/styles.scss",
              "node_modules/@fortawesome/fontawesome-free/css/all.min.css",
              "node_modules/ol/ol.css",
              "./node_modules/leaflet/dist/leaflet.css",
              {
                "input": "src/styles/combined-css/main-style.min.css",
                "bundleName": "mainLtrStyle",
                "inject": false
              },
              {
                "input": "src/styles/combined-css/main-style.rtl.min.css",
                "bundleName": "mainRtlStyle",
                "inject": false
              }
            ],
            "scripts": [
              "./node_modules/@popperjs/core/dist/umd/popper.min.js"
            ],
            "vendorChunk": true,
            "extractLicenses": false,
            "buildOptimizer": false,
            "sourceMap": true,
            "optimization": false,
            "namedChunks": true
          },
          "configurations": {
            "staging": {
              "baseHref": "/alkaram-control-panel-staging/",
              "budgets": [
                {
                  "type": "initial",
                  "maximumWarning": "2mb",
                  "maximumError": "5mb"
                },
                {
                  "type": "anyComponentStyle",
                  "maximumWarning": "6kb",
                  "maximumError": "10kb"
                }
              ],
              "fileReplacements": [
                {
                  "replace": "src/environments/environment.ts",
                  "with": "src/environments/environment.staging.ts"
                }
              ],
              "outputHashing": "all",
              "optimization": true,
              "sourceMap": false,
              "namedChunks": false,
              "extractLicenses": true,
              "vendorChunk": false,
              "buildOptimizer": true
            },
            "production": {
              "baseHref": "/",
              "budgets": [
                {
                  "type": "initial",
                  "maximumWarning": "2mb",
                  "maximumError": "5mb"
                },
                {
                  "type": "anyComponentStyle",
                  "maximumWarning": "6kb",
                  "maximumError": "10kb"
                }
              ],
              "fileReplacements": [
                {
                  "replace": "src/environments/environment.ts",
                  "with": "src/environments/environment.prod.ts"
                }
              ],
              "outputHashing": "all",
              "optimization": true,
              "sourceMap": false,
              "namedChunks": false,
              "extractLicenses": true,
              "vendorChunk": false,
              "buildOptimizer": true
            },
            "development": {}
          },
          "defaultConfiguration": "production"
        },
        "serve": {
          "builder": "@angular-builders/custom-webpack:dev-server",
          "configurations": {
            "staging": {
              "browserTarget": "control-panel:build:staging"
            },
            "production": {
              "browserTarget": "control-panel:build:production"
            },
            "development": {
              "browserTarget": "control-panel:build:development"
            }
          },
          "defaultConfiguration": "development"
        },
        "extract-i18n": {
          "builder": "@angular-builders/custom-webpack:extract-i18n",
          "options": {
            "browserTarget": "control-panel:build"
          }
        },
        "test": {
          "builder": "@angular-builders/custom-webpack:karma",
          "options": {
            "main": "src/test.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "tsconfig.spec.json",
            "karmaConfig": "karma.conf.js",
            "inlineStyleLanguage": "scss",
            "assets": [
              "src/favicon.ico",
              "src/assets",
              "src/firebase-messaging-sw.js",
              "src/.htaccess",
              {
                "glob": "**/*",
                "input": "./node_modules/leaflet/dist/images",
                "output": "assets/"
              }
            ],
            "styles": [
              "src/styles.scss",
              "node_modules/@fortawesome/fontawesome-free/css/all.min.css",
              "node_modules/ol/ol.css",
              "./node_modules/leaflet/dist/leaflet.css",
              {
                "input": "src/styles/css/main-style.min.css",
                "bundleName": "mainLtrStyle",
                "inject": false
              },
              {
                "input": "src/styles/css/main-style.rtl.min.css",
                "bundleName": "mainRtlStyle",
                "inject": false
              }
            ],
            "scripts": [
              "./node_modules/@popperjs/core/dist/umd/popper.min.js"
            ]
          }
        }
      }
    }
  }
}

内容的提问来源于stack exchange，提问作者user20140095