css color之线性linear-gradient()函数

CSS linear-gradient() 函数用于创建一个表示两种或多种颜色线性渐变的图片。其结果属于<gradient>数据类型，是一种特别的<image>数据类型。

linear-gradient( [ <angle> | to <side-or-corner> ,]? <color-stop-list> )

  \---------------------------------/ \----------------------------/

    Definition of the gradient line        List of color stops 

where <side-or-corner> = [ left | right ] || [ top | bottom ]

  and <color-stop-list> = [ <linear-color-stop> [, <color-hint>? ]? ]#, <linear-color-stop>

  and <linear-color-stop> = <color> [ <color-stop-length> ]?

  and <color-stop-length> = [ <percentage> | <length> ]{1,2}

  and <color-hint> = [ <percentage>

PS：是否可用于任何元素，包括文本？？

栗子：

div {

  background: linear-gradient(to right, red, orange, yellow, green, blue, indigo, violet);

}