& ltdiv id = " main " & gt& lt/div & gt；
& ltdiv id = " h " & gt& lt/div & gt；
& ltdiv id = " b " & gt& lt/div
& ltdiv id = " main " & gt& lt/div & gt；
& ltdiv id = " h " & gt& lt/div & gt；
& ltdiv id = " b " & gt& lt/div & gt；
& ltdiv id = " c " & gt& lt/div & gt； .
Another class selector is class. The form is the same as this.
& ltdiv class="main " >& lt/div & gt；
& ltdiv class="h " >& lt/div & gt；
& ltdiv class="b " >& lt/div & gt；
& ltdiv class="c " >& lt/div & gt； .
As for the difference between id and class, you can check it online. There are many. There are several websites here. Take a look.
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