What new units are added in css3-Front-end Q&A-php.cn

Home

Web Front-end

Front-end Q&A

What new units are added in css3

青灯夜游

Jan 12, 2022 pm 05:17 PM

css3unit

New units added in css3: 1. "ch", the width of character 0; 2. "rem", a relative unit, mainly relative to the size of the root element font; 3. "vw", the window Width; 4. "vh", window height; 5. "vmin"; 6. "vmax", etc.

What new units are added in css3

The operating environment of this tutorial: Windows 7 system, CSS3&&HTML5 version, Dell G3 computer.

New length units in CSS3

The new length units in CSS3 are as follows,

ch, the width of character 0
rem, is a relative unit, mainly relative to the size of the root element font, To use rem, we need to refer to the specified root element.
vw, viewpoint width, window width, 1vw=1% of the window width
vh, viewpoint height, window height, 1vh=1% of the window height
vmin, vmax, etc.

The newly added viewpoint-related units are generally targeted at mobile devices.

rem is actually the same thing as em, except that rem has an additional restriction, which represents the root element (html element) font-size. We can take a look at the difference between

rem and em through the following example,

<html style="font-size: 12px;">
<body>
    <div id="div1" style="font-size: 16px">
        <div id="div2" style="font-size: 1.2em"></div>
        <div id="div3" style="font-size: 1.2rem">
            <div id="div4" style="font-size: 1.2em"></div>
        </div>
    </div>
</body>
</html>

At this time,

font-size of div2: 16px*1.2em=19.2px
##font-size of div3:
12px*1.2 rem=14.4px
font-size of div4:
12px*1.2rem*1.2em=17.28px

It can be seen that

rem does not have a cascading relationship, but em does.

It is worth noting that IE8 and below, Safari 4, IOS 3.2, etc. do not support

rem units.

(Learning video sharing:

css video tutorial)

The above is the detailed content of What new units are added in css3. For more information, please follow other related articles on the PHP Chinese website!

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Mastering CSS Selectors: Class vs. ID for Efficient StylingMay 16, 2025 am 12:19 AM

The use of class selectors and ID selectors depends on the specific use case: 1) Class selectors are suitable for multi-element, reusable styles, and 2) ID selectors are suitable for unique elements and specific styles. Class selectors are more flexible, ID selectors are faster to process but may affect code maintenance.

HTML5 Specification: Exploring the Key Goals and MotivationsMay 16, 2025 am 12:19 AM

ThekeygoalsandmotivationsbehindHTML5weretoenhancesemanticstructure,improvemultimediasupport,andensurebetterperformanceandcompatibilityacrossdevices,drivenbytheneedtoaddressHTML4'slimitationsandmeetmodernwebdemands.1)HTML5aimedtoimprovesemanticstructu

CSS IDs and Classes : a simple guideMay 16, 2025 am 12:18 AM

IDsareuniqueandusedforsingleelements,whileclassesarereusableformultipleelements.1)UseIDsforuniqueelementslikeaspecificheader.2)Useclassesforconsistentstylingacrossmultipleelementslikebuttons.3)BecautiouswithspecificityasIDsoverrideclasses.4)Useclasse

HTML5 Goals: Understanding the Key Objectives of the SpecificationMay 16, 2025 am 12:16 AM

HTML5aimstoenhancewebaccessibility,interactivity,andefficiency.1)Itsupportsmultimediawithoutplugins,simplifyinguserexperience.2)Semanticmarkupimprovesstructureandaccessibility.3)Enhancedformhandlingincreasesusability.4)Thecanvaselementenablesdynamicg

Is it difficult to use HTML5 to achieve its goals?May 16, 2025 am 12:06 AM

HTML5isnotparticularlydifficulttousebutrequiresunderstandingitsfeatures.1)Semanticelementslike,,,andimprovestructure,readability,SEO,andaccessibility.2)Multimediasupportviaandelementsenhancesuserexperiencewithoutplugins.3)Theelementenablesdynamic2Dgr

CSS: Can I use multiple IDs in the same DOM?May 14, 2025 am 12:20 AM

No,youshouldn'tusemultipleIDsinthesameDOM.1)IDsmustbeuniqueperHTMLspecification,andusingduplicatescancauseinconsistentbrowserbehavior.2)Useclassesforstylingmultipleelements,attributeselectorsfortargetingbyattributes,anddescendantselectorsforstructure

The Aims of HTML5: Creating a More Powerful and Accessible WebMay 14, 2025 am 12:18 AM

HTML5aimstoenhancewebcapabilities,makingitmoredynamic,interactive,andaccessible.1)Itsupportsmultimediaelementslikeand,eliminatingtheneedforplugins.2)Semanticelementsimproveaccessibilityandcodereadability.3)Featureslikeenablepowerful,responsivewebappl

Significant Goals of HTML5: Enhancing Web Development and User ExperienceMay 14, 2025 am 12:18 AM

HTML5aimstoenhancewebdevelopmentanduserexperiencethroughsemanticstructure,multimediaintegration,andperformanceimprovements.1)Semanticelementslike,,,andimprovereadabilityandaccessibility.2)andtagsallowseamlessmultimediaembeddingwithoutplugins.3)Featur

See all articles