Relationship of EM PX

In this case, the two commonly used units in CSS that define the font size are em and PX.

Em is a relative logarithm. For example, 1.1em represents the width of 1.1 characters, and the width of this character is initialized Based on font-size. At the same time, EM also inherits the features of the parent object, so 1.2em in different locations is not necessarily equal, but this articleArticleIt does not matter.
Px indicates the resolution of the current display device. Although the size difference still exists between different devices, it is more suitable for defining fonts.
This template does not specifically define the font size of the search part, so it uses the font-size parameter 12px of the parent object. The font size defined by Internet Explorer is different from that defined by FF/opera. By default, 1 em looks bigger in IE than other browsers, therefore, you must add the following definitions to the body:CopyCodeCode: font-size: 62.5%;
Font-family: 'lucida grande', verdana, Arial, sans-serif;

The key is the first sentence, which makes the font size of IE look like 1em = 10px, which is similar to FF/opera.