"targeting elements is like choosing wich part of your house you'd like to style"

e.g.make all links another color

CSS

a {
    color: red;
}
doing this makes all the links red
or change the background (wall) color of the page

CSS

body {
    background-color: hotpink;
}

"div & classes is like putting your stuff into cabinets and naming them"

change an element with a certain class

CSS 

.classname {
    color: lightgreen;
}

HTML

<div class="classname">
    <!-- your content goes in here -->
</div>
let's also change the corners to be round

CSS

.classname {
    color: lightgreen;
    border-radius: 10px;
}

HTML

<div class="classname">
    <!-- your content goes in here -->
</div>

changing fonts

put all the paragraph tags a typewriter font

CSS

p {
    font-family: typewriter;
}

would you look at that!

"text decorations speaks for itself"

put a red underline under text with the class "underline"

CSS

.highlight {
    text-decoration: red 1px underline;;
}
                        

HTML

<p>this is a <span class="underline">splelling misteake.</span></p>

this is an underline.

styling divs

make a div of 300 by 60 pixels

CSS

.cube {
    width: 300px;
    height: 60px;
    background-color: red;
}
                        

HTML                        

<div class="cube">
    <!-- you can put some text in here, or leave it empty -->
</div>

background images

make this div have a background image of a cat (and make the text pink)

CSS

.cat {
    background-image: url("cat.jpg");
    background-size: cover; /* make sure the background is resized to fit the div. */
    color: hotpink;
}
                        

HTML

<div class="cat">
    <!-- your content in here -->
</div>