--- id: 587d778e367417b2b2512aab title: Improve Readability with High Contrast Text challengeType: 0 videoUrl: '' localeTitle: 使用高对比度文本提高可读性 --- ## Description

前景色和背景色之间的低对比度会使文本难以阅读。充足的对比度可以提高内容的可读性，但“足够”究竟意味着什么呢？ Web内容可访问性指南（WCAG）建议正常文本的对比度至少为4.5：1。通过比较两种颜色的相对亮度值来计算该比率。对于相同的颜色，或者没有对比度，其范围从1：1到白色与黑色的21：1，最强的对比度。网上有许多对比度检查工具可以为您计算这个比率。

## Instructions

Camper Cat在他最近的博客文章中选择浅灰色文本在白色背景上具有1.5：1的对比度，使其难以阅读。将文本color从当前灰色（ #D3D3D3 ）更改为深灰色（ #636363 ），将对比度提高到6：1。

## Tests

```yml tests: - text: 您的代码应该改变文字color为body的深灰色。 testString: 'assert($("body").css("color") == "rgb(99, 99, 99)", "Your code should change the text color for the body to the darker gray.");' - text: 您的代码不应更改body的background-color 。 testString: 'assert($("body").css("background-color") == "rgb(255, 255, 255)", "Your code should not change the background-color for the body.");' ```

## Challenge Seed

```html

Deep Thoughts with Master Camper Cat

A Word on the Recent Catnip Doping Scandal

The influence that catnip has on feline behavior is well-documented, and its use as an herbal supplement in competitive ninja circles remains controversial. Once again, the debate to ban the substance is brought to the public's attention after the high-profile win of Kittytron, a long-time proponent and user of the green stuff, at the Claw of Fury tournament.

As I've stated in the past, I firmly believe a true ninja's skills must come from within, with no external influences. My own catnip use shall continue as purely recreational.

```

## Solution

```js // solution required ```