WEBVTT

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Okay, now you know how to change 
the contents of an element

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and the values of its attributes.

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What else is left? Well, what if 
we wanted to change its style?

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Normally, we would do that in CSS, 
but there are some times when we

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want to do that in JavaScript, like when
we want to animate styles over time or

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change them after a user clicks something, 
which we'll see how to do soon, I promise.

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Let's change the style of this heading.

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If we did that in CSS, 
it would look like this--

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`#heading` to select by ID,
and then we'll say `color: orange`.

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Ta da, it's orange, just like the cat.

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Now, to do that in JavaScript,

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we first find the heading element, 
which we have here.

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Then, we're going to access 
its style attribute with `.style`.

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Then, we access the property 
that we're interested in-- `color`--

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and set it equal to the new value.

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Let's delete the property in CSS to 
see if it worked. Yup, it worked.

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Now, notice down here we've got two dots
because we're actually accessing

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two objects. One of them is the element
object and the other is the style object

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that contains all the styles for that 
element as different properties.

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What if we also wanted to change the
background color of that heading?

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In CSS it would be 
`background-color: black;`

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Let's try that in JavaScript. So

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`headingEl.style.background-color 
= "black";`

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Uh oh, we have an error. 
This is actually invalid JavaScript,

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because property names 
can't contain hyphens.

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Instead we need to convert this CSS
property name to a form that's valid

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JavaScript, which we do by camel-casing it.
Remove the hyphen and capitalize the "c".

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And let's go test it out by deleting this property here, and yep, it's still black.

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Now that I'm getting fancy, I want 
to make the heading center aligned too.

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So I will add one more line down here.

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`headingEl.style.textAlign`-- 
which we camel-case-- `= "center"`.

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Once again, we camel-case it since it 
was two words with a hyphen before,

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and now we've got this heading that looks
like our cat and also like Halloween. Yay.