Where's the problem?Why the header color isn't changing?

Question

HTML

<div class="Header"">
<h1>
<b>Blogger</b>Sanjid
</h1>
</div>

CSS

div .Header{
color: green;
}

Answer 1

That's because your CSS selector is incorrect. You are selecting all .Header elements inside all div elements.
Remove the 'div' at the start.
Like this:
https://code.sololearn.com/WlM93rby5Hgd/?ref=app