vue鼠标点击标题滚动到指定模块，如果滚动页面到指定模块的话标题同样改变颜色

<script>
export default {
  name: 'ceshi',
  data() {
    return {
      activeSection: 0, // 默认激活第一个标题
      sections: [
        { title: 'Section 1', content: 'Content for section 1' },
        { title: 'Section 2', content: 'Content for section 2' },
        { title: 'Section 3', content: 'Content for section 3' },
      ],
    };
  },
  mounted() {
    window.addEventListener('scroll', this.handleScroll);
  },
  beforeDestroy() {
    window.removeEventListener('scroll', this.handleScroll);
  },
  methods: {
    scrollToSection(index) {
      const section = this.$refs.sectionsRef[index];
      section.scrollIntoView({ behavior: 'smooth' });
      this.activeSection = index;
    },
    handleScroll() {
      const sections = this.$refs.sectionsRef;
      let currentActiveSection = 0;

      sections.forEach((section, index) => {
        const sectionTop = section.offsetTop;
        if (window.scrollY >= sectionTop - 50) { // 50 是为了调整滚动时的误差
          currentActiveSection = index;
        }
      });

      this.activeSection = currentActiveSection;
    },
    isActiveSection(index) {
      return this.activeSection === index;
    },
  },
}
</script>

<template>
  <div id="app">
    <div class="nav">
      <div
        v-for="(section, index) in sections"
        :key="index"
        class="nav-item"
        :class="{ active: isActiveSection(index) }"
        @click="scrollToSection(index)"
      >
        {{ section.title }}
      </div>
    </div>
    <div class="content">
      <div
        v-for="(section, index) in sections"
        :key="index"
        :id="'section-' + index"
        class="section"
        ref="sectionsRef"
      >
        <h2>{{ section.title }}</h2>
        <p>{{ section.content }}</p>
      </div>
    </div>
  </div>
</template>

<style scoped lang="scss">
#app {
  font-family: Avenir, Helvetica, Arial, sans-serif;
  text-align: center;
  color: #2c3e50;
  margin-top: 60px;
}

.nav {
  position: fixed;
  top: 0;
  width: 100%;
  background: #fff;
  border-bottom: 1px solid #ddd;
  display: flex;
  justify-content: center;
}

.nav-item {
  padding: 15px;
  cursor: pointer;
  transition: color 0.3s;
}

.nav-item.active {
  color: #42b983; /* 改变激活标题的颜色 */
}

.content {
  margin-top: 60px; /* 留出导航栏的空间 */
}

.section {
  height: 400px; /* 每个模块的高度，可以根据需要调整 */
  border-bottom: 1px solid #ddd;
  padding: 20px;
  box-sizing: border-box;
}
</style>