background: url('@/assets/tylogo.png') no-repeat 20% top / 200px auto 在这段代码的基础上额外使其上移200px

在这段 CSS 代码中，`background` 属性设置了背景图片、位置、大小和重复方式。如果要让这个背景图片上移 200px，你需要在 `top` 值上增加相应的负值。考虑到之前的 `top` 值是 `20%`，我们可以将其修改为 `top: 20% + 200px`。但是，百分比不会直接和像素相加，所以我们需要将其转换成像素。首先计算出20%对应的具体像素数值，然后加上200。

假设100%等于视口宽度，那么20%大约等于视口宽度的四分之一。现在，我们需要计算出这个值，然后再加上200px。以下是计算后的完整代码示例：

background: url('@/assets/tylogo.png') no-repeat 20% calc(20% + 200px) / 200px auto;

这里 `calc(20% + 200px)` 计算了从顶部开始上移的具体像素值，并应用到了 `top` 属性。

注意：如果浏览器支持百分比单位和 `auto` 一起使用，上述 `calc` 表达式可以直接使用，如果不支持，可能需要调整为其他方法，比如使用 JavaScript 来动态设置样式。

相关问题

优化下面代码.bg { width: 100%; height: 100vh; background-image: url('../../assets/img/info-bg.png'); background-size: 100% 100%; background-repeat: no-repeat; position: relative; font-family: AlibabaPuHuiTiR; .goBack { position: absolute; top: 34px; right: 65px; cursor: pointer; color: #ffffff; width: 181px; padding: 15px 10px; background: rgba(24, 31, 30, 0.52); border: 1px solid #4a524e; border-radius: 5px; font-size: 18px; font-family: AlibabaPuHuiTiR; z-index: 111; display: flex; flex-direction: row; justify-content: space-between; align-items: center; } .home-left { position: absolute; top: 18%; left: 40px; width: 41%; height: 76%; font-size: 24px; color: #ffffff; } .unit { font-size: 24px; color: #636363; } .home-left-title { font-size: 24px; color: #ffffff; line-height: 36px; } .home-right { position: absolute; top: 18%; right: 88px; width: 46%; height: 78%; } .model { display: flex; justify-content: center; align-items: center; height: 90%; } #threeContained { width: 100%; height: 100%; } .model-qk-img { width: 82%; height: 90%; background-image: url('../../assets/img/howo.png'); background-size: 100% 100%; background-repeat: no-repeat; } .model-zk-img { width: 56%; height: 90%; background-image: url('../../assets/img/heavyT.png'); background-size: 100% 100%; background-repeat: no-repeat; } .model-gj-img { width: 82%; height: 90%; background-image: url('../../assets/img/transit.png'); background-size: 100% 100%; background-repeat: no-repeat; } .car-online { margin-bottom: 50px; } } .day-data { display: flex; flex-direction: row; justify-content: space-between; align-items: center; height: 29%; margin-left: 30px; } .day-val { width: 40%; } .prefix { display: inline-block; width: 6px; height: 14px; background: #ffffff; margin-right: 20px; } .zh-title { margin-left: 30px; padding-top: 30px; font-size: 30px; font-weight: 700; text-align: left; color: #ffffff; line-height: 32px; letter-spacing: 0.3px; font-family: AlibabaPuHuiTiB; } .en-title { margin-left: 30px; font-size: 14px; font-weight: 400; text-align: left; color: #ffffff; line-height: 32px; letter-spacing: -0.91px; font-family: AlibabaPuHuiTiR; }

Here are some suggestions to optimize the code:

1. Use shorthand properties whenever possible. For example, instead of writing `background-size: 100% 100%;`, you can write `background-size: cover;`.

2. Consolidate similar styles into classes, instead of repeating them for every element. For example, you can create a class for the font family and apply it to all elements that use that font.

3. Remove unnecessary styles that are not being used or overwritten by other styles.

4. Use more specific selectors to target elements, instead of relying on the order of elements in the HTML. This will make the code more robust and easier to maintain.

5. Consider using a CSS preprocessor like Sass or Less, which can help you write cleaner and more organized code.

Here's an example of how the code could be optimized:

.bg {
  width: 100%;
  height: 100vh;
  background: url('../../assets/img/info-bg.png') no-repeat center center / cover;
  position: relative;
  font-family: AlibabaPuHuiTiR;
}

.goBack {
  position: absolute;
  top: 34px;
  right: 65px;
  cursor: pointer;
  color: #fff;
  width: 181px;
  padding: 15px 10px;
  background: rgba(24, 31, 30, 0.52);
  border: 1px solid #4a524e;
  border-radius: 5px;
  font-size: 18px;
  font-family: AlibabaPuHuiTiR;
  z-index: 111;
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  align-items: center;
}

.home-left {
  position: absolute;
  top: 18%;
  left: 40px;
  width: 41%;
  height: 76%;
  font-size: 24px;
  color: #fff;
}

.unit {
  font-size: 24px;
  color: #636363;
}

.home-left-title {
  font-size: 24px;
  color: #fff;
  line-height: 36px;
}

.home-right {
  position: absolute;
  top: 18%;
  right: 88px;
  width: 46%;
  height: 78%;
}

.model {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 90%;
}

#threeContained {
  width: 100%;
  height: 100%;
}

.model-qk-img {
  width: 82%;
  height: 90%;
  background: url('../../assets/img/howo.png') no-repeat center center / cover;
}

.model-zk-img {
  width: 56%;
  height: 90%;
  background: url('../../assets/img/heavyT.png') no-repeat center center / cover;
}

.model-gj-img {
  width: 82%;
  height: 90%;
  background: url('../../assets/img/transit.png') no-repeat center center / cover;
}

.car-online {
  margin-bottom: 50px;
}

.day-data {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 29%;
  margin-left: 30px;
}

.day-val {
  width: 40%;
}

.prefix {
  display: inline-block;
  width: 6px;
  height: 14px;
  background: #fff;
  margin-right: 20px;
}

.zh-title {
  margin-left: 30px;
  padding-top: 30px;
  font-size: 30px;
  font-weight: 700;
  text-align: left;
  color: #fff;
  line-height: 32px;
  letter-spacing: 0.3px;
  font-family: AlibabaPuHuiTiB;
}

.en-title {
  margin-left: 30px;
  font-size: 14px;
  font-weight: 400;
  text-align: left;
  color: #fff;
  line-height: 32px;
  letter-spacing: -0.91px;
  font-family: AlibabaPuHuiTiR;
}

.font-alibaba {
  font-family: AlibabaPuHuiTiR;
}

.font-alibaba-bold {
  font-family: AlibabaPuHuiTiB;
}

把这段less代码，转换成scss代码：.select-box { height: 420px; overflow-y: auto; li { padding: 5px 0; i { float: right; padding-left: 24px; padding-right: 10px; color: #3195f8; font-size: 12px; cursor: pointer; background: url(~@/assets/images/next_level_active.png) no-repeat 10px center; border-left: 1px solid rgb(238, 238, 238); } a.active+i { color: rgb(197, 197, 197); background-image: url(~@/assets/images/next_level.png); pointer-events: none; } img { width: 14px; vertical-align: middle; margin-right: 5px; } } }

.select-box {
height: 420px;
overflow-y: auto;
li {
padding: 5px 0;
i {
float: right;
padding-left: 24px;
padding-right: 10px;
color: red;
}
}
}

转换后的 SCSS 代码如上。