css selectors - What #id.class css means? -

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• how combine class , id in css selector? 9 answers

i saw in css declaration this:

#nav.js {     display:none; } 

can explain means? html code following

<ul id="nav">     <li><a href="#">home3</a></li>     <li><a href="#">about</a></li>     <li><a href="#">contact</a></li> </ul> 

#nav.js

this selects element id set "nav" , has class containing "js".

for example, select of following elements:

<figure id="nav" class="js"></figure> <figure id="nav" class="foo js"></figure> <figure id="nav" class="js bar"></figure> <figure id="nav" class="foo js bar"></figure> 

but wouldn't select of these elements:

<figure></figure> <figure id="nav"></figure> <figure class="js"></figure> <figure id="nav" class="foo bar"></figure> 

display: none

this i'm sure you're aware sets element not display @ on page.

#nav.js { display: none; }

this combines above. selects element id of "nav" , class containing "js" , sets not display on page.