In CSS, you can set the font size through the font-size attribute, and the syntax format is "font-size: value;". The value of this attribute can be keywords such as "small", "large", "smaller", "larger", etc.; it can also be a value in px, em, rem, or % units.
The operating environment of this article: Acer S40-51, CSS3&&HTML5&&HBuilderX.3.0.5 version, Windows10 Home Chinese version
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In CSS, you can use the font-size attribute to adjust the font size; the font-size attribute is used to set the font size. If an element does not explicitly define the font-size attribute, it will automatically inherit the calculation result of the font-size attribute of the parent element.
Note that the font-size attribute actually sets the height of the character boxes in the font; the actual character glyph may be taller or shorter than these boxes (usually shorter).
Attribute values that can be set:
Example 1:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <style type="text/css"> /* font-size属性设置字体大小--“数字+长度值” */ .length1 { font-size: 20px; /* px,像素,它是 CSS 中最常用的长度单位,可以用来指定字体大小,元素的宽度、高度、边框、内边距,外边距的大小等等, 它是一个虚拟长度单位,是计算机系统的数字化图像长度单位,如果px要换算成物理长度,需要指定精度DPI px 单位的值必须是整数值 */ } .length2 { font-size: 2em; /* em 相对长度单位,取决于目标元素字体尺寸。 em 单位的值等于基本元素或父元素的字体大小。 */ } .length3 { font-size: 2rem; /* rem CSS3中加入的 相对长度单位, 取决于文档根元素(通常为:root)的字体尺寸,适用于依据字体尺寸进行的排版,适用于自适应。 */ } .length4{ font-size:200%; /* 相对于父元素的尺寸的取值, 实际使用中,如果父元素是一个非稳定的取值,可能会导致父元素被撑开, 而实际值取决于其祖先元素中最近的一个拥有稳定取值的元素。整数取值,并不适用于解决自适应问题。 */ } </style> </head> <body> <p>这是测试段落</p> <p class="length1">这是测试段落</p> <p class="length2">这是测试段落</p> <p class="length3">这是测试段落</p> <p class="length4">这是测试段落</p> </body> </html>
Effect Picture:
##Example 2:
<!DOCTYPE html> <html> <head> <style type="text/css"> /* font-size属性设置字体大小--相对大小值 */ .larger { font-size: larger; /* 把 font-size 设置为比父元素更大的尺寸。 */ } .smaller { font-size: smaller; /* 把 font-size 设置为比父元素更小的尺寸。 */ } </style> </head> <body> <p>这是测试段落</p> <p class="larger">这是测试段落</p> <p class="smaller">这是测试段落</p> </body> </html>Rendering:
Example 3:
<!DOCTYPE html> <html> <head> <style type="text/css"> /*font-size属性设置字体大小--绝对大小值*/ .xx-small {font-size: xx-small;} .x-small {font-size: x-small;} .small {font-size: small;} .medium {font-size: medium;} .large {font-size: large;} .x-large {font-size: x-large;} .xx-large {font-size: xx-large;} </style> </head> <body> <p>这是测试段落</p> <p class="medium">这是测试段落</p> <p class="xx-small">这是测试段落</p> <p class="x-small">这是测试段落</p> <p class="small">这是测试段落</p> <p class="large">这是测试段落</p> <p class="x-large">这是测试段落</p> <p class="xx-large">这是测试段落</p> </body> </html>Rendering:
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