<template>
  <div>
    <div class="banner">
      <div class="banner-desc">
        <h1>{{ langConfig[1] }}</h1>
        <p>{{ langConfig[2] }}</p>
      </div>
    </div>
    <div ref="indexMainImg" class="jumbotron">
      <img src="~examples/assets/images/theme-index-blue.png" alt="">
      <div
        class="jumbotron-red"
        :style="{
          height: mainImgOffset + 'px'
        }"
      >
        <img src="~examples/assets/images/theme-index-red.png" alt="">
      </div>
    </div>
    <div class="sponsors">
      <a class="sponsor" href="https://www.duohui.cn/?utm_source=element&utm_medium=web&utm_campaign=element-index" target="_blank">
        <img width="45" src="~examples/assets/images/duohui.svg" alt="duohui">
        <div>
          <p>{{ sponsorLabel }} <span class="name">多会</span></p>
          <p>活动服务销售平台</p>
        </div>
      </a>
      <a
        class="sponsor"
        href="https://bit.dev/?from=element-ui"
        target="_blank"
      >
        <img width="45" src="~examples/assets/images/bit.svg" alt="bit">
        <div>
          <p>{{ sponsorLabel }} <span class="name">bit</span></p>
          <p>Share Code</p>
        </div>
      </a>
    </div>
    <div class="cards">
      <ul class="container">
        <li>
          <div class="card">
            <img src="~examples/assets/images/guide.png" alt="">
            <h3>{{ langConfig[3] }}</h3>
            <p>{{ langConfig[4] }}</p>
            <router-link
              active-class="active"
              :to="`/${ lang }/guide/design`"
              exact
            >
              {{ langConfig[5] }}
            </router-link>
          </div>
        </li>
        <li>
          <div class="card">
            <img src="~examples/assets/images/component.png" alt="">
            <h3>{{ langConfig[6] }}</h3>
            <p>{{ langConfig[7] }}</p>
            <router-link
              active-class="active"
              :to="`/${ lang }/component/layout`"
              exact
            >
              {{ langConfig[5] }}
            </router-link>
          </div>
        </li>
        <li>
          <div class="card">
            <img src="~examples/assets/images/resource.png" alt="">
            <h3>{{ langConfig[8] }}</h3>
            <p>{{ langConfig[9] }}</p>
            <router-link
              active-class="active"
              :to="`/${ lang }/resource`"
              exact
            >
              {{ langConfig[5] }}
            </router-link>
          </div>
        </li>
      </ul>
    </div>
  </div>
</template>
<script>
import pageLang from '../i18n/page.json'
import { throttle } from 'throttle-debounce'

export default {
  data() {
    return {
      lang: this.$route.meta.lang,
      mainImgOffset: 0,
    }
  },
  computed: {
    sponsorLabel() {
      return this.lang === 'zh-CN' ? '赞助商' : 'Sponsored by'
    },
    langConfig() {
      return pageLang.filter(config => config.lang === this.lang)[0].pages.index
    },
  },
  created() {
    this.throttledHandleScroll = throttle(10, true, index => {
      this.handleScroll(index)
    })
  },
  beforeUnmount() {
    const dom = document.querySelector('#app>.el-scrollbar>.el-scrollbar__wrap.el-scrollbar__wrap--hidden-default')
    dom.removeEventListener('scroll', this.throttledHandleScroll)
  },
  mounted() {
    const dom = document.querySelector('#app>.el-scrollbar>.el-scrollbar__wrap.el-scrollbar__wrap--hidden-default')
    dom.addEventListener('scroll', this.throttledHandleScroll)
  },
  methods: {
    handleScroll() {
      const ele = this.$refs.indexMainImg
      const rect = ele.getBoundingClientRect()
      const eleHeight = ele.clientHeight + 55
      let calHeight = (180 - rect.top) * 2
      if (calHeight < 0) calHeight = 0
      if (calHeight > eleHeight) calHeight = eleHeight
      this.mainImgOffset = calHeight
    },
  },
}
</script>
<style lang="scss" scoped>
.banner {
  text-align: center;
}
.banner-desc {
  padding-top: 30px;

  h1 {
    font-size: 34px;
    margin: 0;
    line-height: 48px;
    color: #555;
  }

  p {
    font-size: 18px;
    line-height: 28px;
    color: #888;
    margin: 20px 0 5px;
  }
}
.sponsors {
  display: flex;
  justify-content: center;
}
.sponsor {
  margin: 0 20px 50px;
  display: inline-flex;
  width: 300px;
  height: 100px;
  justify-content: center;

  .name {
    font-weight: bold;
    color: #666;
  }

  img {
    margin-right: 20px;
  }

  div {
    display: flex;
    flex-direction: column;
    justify-content: center;
  }

  p {
    margin: 0;
    line-height: 1.8;
    color: #999;
    font-size: 14px;
  }
}
.jumbotron {
  width: 890px;
  margin: 30px auto;
  position: relative;
  img {
    width: 100%;
  }
  .jumbotron-red {
    transition: height .1s;
    background: #FFF;
    position: absolute;
    left: 0;
    top:0;
    overflow: hidden;
  }
}
.cards {
  margin: 0 auto 110px;
  width: 1140px;

  .container {
    padding: 0;
    margin: 0 -11px;
    width: auto;
    &::before, &::after {
      display: table;
      content: "";
    }
    &::after {
      clear: both;
    }
  }


  li {
    width: 33.3%;
    padding: 0 19px;
    box-sizing: border-box;
    float: left;
    list-style: none;
  }

  img {
    width: 160px;
    height: 120px;
  }
}
.card {
  height: 430px;
  width: 100%;
  background:#ffffff;
  border:1px solid #eaeefb;
  border-radius:5px;
  box-sizing: border-box;
  text-align: center;
  position: relative;
  transition: all .3s ease-in-out;
  bottom: 0;

  img {
    margin: 66px auto 60px;
  }
  h3 {
    margin: 0;
    font-size: 18px;
    color: #1f2f3d;
    font-weight: normal;
  }
  p {
    font-size: 14px;
    color: #99a9bf;
    padding: 0 25px;
    line-height: 20px;
  }
  a {
    height: 53px;
    line-height: 52px;
    font-size: 14px;
    color: #409EFF;
    text-align: center;
    border: 0;
    border-top: 1px solid #eaeefb;
    padding: 0;
    cursor: pointer;
    width: 100%;
    position: absolute;
    bottom: 0;
    left: 0;
    background-color: #fff;
    border-radius: 0 0 5px 5px;
    transition: all .3s;
    text-decoration: none;
    display: block;

    &:hover {
      color: #fff;
      background: #409EFF;
    }
  }
  &:hover {
    bottom: 6px;
    box-shadow: 0 6px 18px 0 rgba(232,237,250,0.50);
  }
}
@media (max-width: 1140px) {
  .cards {
    width: 100%;
    .container {
      width: 100%;
      margin: 0;
    }
  }
  .banner .container {
    width: 100%;
    box-sizing: border-box;
  }
  .banner img {
    right: 0;
  }
}

@media (max-width: 1000px) {
  .banner .container {
    img {
      display: none;
    }
  }
  .jumbotron {
    display: none;
  }
}

@media (max-width: 768px) {
  .cards {
    li {
      width: 80%;
      margin: 0 auto 20px;
      float: none;
    }
    .card {
      height: auto;
      padding-bottom: 54px;
    }
  }
  .banner-stars {
    display: none;
  }
  .banner-desc {
    #line2 {
      display: none;
    }
    h2 {
      font-size: 32px;
    }
    p {
      width: auto;
    }
  }
}
.theme-intro-b {
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  z-index: 200;
  .intro-banner {
    position: absolute
  }
  img {
    width: 300px;
  }
  .title {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    color: #FFF;
    text-align: center;
    font-weight: bold;
    font-size: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    p {
      padding: 0;
      margin: 10px 0;
    }
  }
}
.theme-intro-a {
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  z-index: 200;
  .mask{
    position: fixed;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    background: #000;
    opacity: .5;
  }
  .intro-banner {
    top: 50%;
    left: 50%;
    position: fixed;
    -webkit-transform: translate(-50%, -50%);
    transform: translate(-50%, -50%);
    box-sizing: border-box;
    text-align: center;
    z-index: 100;
    img {
      width: 100%;
    }
    .intro-text {
      position: absolute;
      top: 50%;
      left: 0;
      right: 0;
      p {
        padding: 0;
        margin: 0;
        font-size: 48px;
        font-weight: bold;
        color: #FFF;
      }
    }
  }
}
</style>
