Many websites are using pixel units that are difficult to adjust in more and more different devices. CSS3 introduces some new units, including REM units, which stands for "root em". This article will share with you It's about the use of REM.
So, how do we use REM?
Suppose we have this CSS:
CSS
article h2 {font-size:20px;}
article p {font-size:12px;}First, we need to determine the px size relative to all fonts. For convenience, the best thing I did was make the root font-size 1px like this:
CSS
html {font-size:1px;}Secondly, we need to change the rest of the font-size values from Pixels are replaced with rem units.
CSS
article h2 {font-size:20rem;}
article p {font-size:12rem;}What REM does, takes 20REM and multiplies it with the root element:
20 REM * 1 PX = 20PX.
Browser Support
IE7 and IE8 still need to use PX values. This will force us to write the font size twice, once in PX and a second time in REM.
CSS
article h2 {font-size:20px; font-size:20rem;}
article p {font-size:12px; font-size:12rem;}The example is as follows:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style type="text/css">
html{font-size:1px;}
article h2{
font-size:20px;/*Support IE7 & IE8*/
font-size:20rem;
}
article p{
font-size:12px;/*Support IE7 & IE8*/
font-size:12rem;
}
</style>
</head>
<body>
<section>
<article>
<h2 id="php中文网">php中文网</h2>
<p>文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字</p>
</article>
<article>
<h2 id="php中文网">php中文网1</h2>
<p>文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字</p>
</article>
<article>
<h2 id="php中文网">php中文网2</h2>
<p>文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字文字</p>
</article>
</section>
</body>
</html>The effect is as follows:
REM has What are the advantages?
Let's assume we need to make all fonts in the website larger by 20%, all we have to do is change the size of the font size in the root element like this:
html {font-size:1.2px;}If You want to reduce the font size by 20%, you would do this:
html{font-size:0.8px;}REM for responsive design
If you want to reduce the font size according to the break in responsive design Click to change all font sizes, it's easier. See example:
@media (min-width: 320px){
html{
font-size:1.4px;
}}
@media (min-width: 600px){
html{
font-size:1.2px;
}}Now in smaller screens we can resize all fonts 40% larger, and in medium screens we resize them 20%.
Use less to solve the need to write content twice - for supporting old browsers
In less or sass you can add functions to save you writing twice times all the time.
You can use the less-font-size function and call it
.font-size(@font-size) {
font-size : @font-size * 1px;
font-size : @font-size * 1rem;
}
article h2 {
.font-size(20);
}The compiled CSS will look like this:
article h2{
font-size:20px;
/*Support IE7 & IE8*/
font-size:20rem;
}The above is the detailed content of Detailed explanation of the usage of REM units in CSS3 (code example). For more information, please follow other related articles on the PHP Chinese website!
Demystifying Screen Readers: Accessible Forms & Best PracticesMar 08, 2025 am 09:45 AMThis is the 3rd post in a small series we did on form accessibility. If you missed the second post, check out "Managing User Focus with :focus-visible". In
Create a JavaScript Contact Form With the Smart Forms FrameworkMar 07, 2025 am 11:33 AMThis tutorial demonstrates creating professional-looking JavaScript forms using the Smart Forms framework (note: no longer available). While the framework itself is unavailable, the principles and techniques remain relevant for other form builders.
Adding Box Shadows to WordPress Blocks and ElementsMar 09, 2025 pm 12:53 PMThe CSS box-shadow and outline properties gained theme.json support in WordPress 6.1. Let's look at a few examples of how it works in real themes, and what options we have to apply these styles to WordPress blocks and elements.
Working With GraphQL CachingMar 19, 2025 am 09:36 AMIf you’ve recently started working with GraphQL, or reviewed its pros and cons, you’ve no doubt heard things like “GraphQL doesn’t support caching” or
Making Your First Custom Svelte TransitionMar 15, 2025 am 11:08 AMThe Svelte transition API provides a way to animate components when they enter or leave the document, including custom Svelte transitions.
Show, Don't TellMar 16, 2025 am 11:49 AMHow much time do you spend designing the content presentation for your websites? When you write a new blog post or create a new page, are you thinking about
Classy and Cool Custom CSS Scrollbars: A ShowcaseMar 10, 2025 am 11:37 AMIn this article we will be diving into the world of scrollbars. I know, it doesn’t sound too glamorous, but trust me, a well-designed page goes hand-in-hand
What the Heck Are npm Commands?Mar 15, 2025 am 11:36 AMnpm commands run various tasks for you, either as a one-off or a continuously running process for things like starting a server or compiling code.
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
SublimeText3 Chinese version
Chinese version, very easy to use
DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software
PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool
Dreamweaver CS6
Visual web development tools
