Set the global default font style
In CSS, you can control the character width by setting the global default font style. You can change the font size by setting the font-size property, while you can change the font style by setting the font-family property. At the same time, you can also control the line height by setting the line height attribute, thus affecting the character width.
Use a specific font
Some fonts have small character widths, such as Monaco and Courier. In web design, you can use these fonts to control the width of characters. Of course, you can use other fonts, but you need to control the character width by setting the font size and line height.
Using CSS framework
There are many CSS frameworks available now, such as Bootstrap, Foundation and so on. Some global styles have been defined in these frameworks, including font size, font style, line height and so on. When using these frameworks, you only need to write HTML and CSS codes according to the specifications of the frameworks, and you don't need to think too much about the character width.