html - What's the difference between CSS id selector and CSS class selector? -

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this question has answer here:

for example, can same results following 2 ways.

 <html>  <head> <style type="text/css">  p#red{color:red}    /* css id selector*/  p.green{color:green}   /* css class selector*/  </style>  </head>  <body>  <p id="red">red color</p> <p class="green">greencolor </p>  </body> </html>

they both can give me colored text. difference between them? answer.

id's unique each element can have 1 id. each page can have 1 element id classes not unique can use same class on multiple elements. can use multiple classes on same element. more about


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